Re: [Discuss-gnuradio] Intel Atom is NICE.
Bob McGwier wrote: And GPU's are going to become commodity priced quickly and possibly even move into the GPP and replace older ways of doing floating point. With Nvidia CUDA, you can write code for your GPP, call GPU with intrinsics to get pretty quick payback while a better longer term strategy is worked on. The future of really hard to program heterogeneous/not symmetric multiple core processors, irrespective of how great the bandwidth is, I don't think is looking all that rosy. It simply cannot take months and months to get speed to make the processor pay or the cost per flop, when ALL COSTS are amortized (expensive people, etc.) begins to look bad. Bob Hello, I bought the earlier version of the motherboard with just the 10/100 ethernet. I put it in a MI-100 case and it is a nice little system. I have not gotten a chance to use it with GNURadio much so I have not commented about it on the list. I am thinking of using it as a car computer. However, I have tried it under Windows XP with my AutumnWave OnAir GT USB HDTV tuner. I understand this tuner uses the computer to decode the HDTV signal. On my older Thinkpad z60t (1.73 GHz Pentium M) the HDTV decode takes about 80% CPU and there are ocassional gliches. I was not happy. With the Intel Atom (1.60 GHz), the HDTV decode takes about 40% CPU and decode is excellent. I suspect the hyperthreading feature of the CPU is causing the improved decoding. I recently bought a Acer Aspire One (Intel Atom and 120GB HD) on sale. I plan to put Linux on it and see how it works with GNURadio and the USRP. I feel the advantage of the Intel Atom is reasonable performance in a small package. The Atom-based netbook may be useful for dealing with ham and conventional narrow-bandwidth signals in a portable/mobile SDR package. The 945 chipset is power hungry but I heard there is another chipset for the Atom in the works. Hopefully the new chipset will allow using the GPU for SDR work. 73 Eric ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
Re: [Discuss-gnuradio] Using gnu-radio for ARM NEON
Philip Balister wrote: Bottom line: companies are still funny about doucmentation for high end products, but attitudes are changing very slowly. Philip Hello, Sometimes it seems the chip makers are really in the documentation business. I was interested in the Marvell 88F5182 SoC as it was used in a NAS I have. Marvell did not have any information on the website and wanted a NDA signed. Then one day I noticed datasheet and user manual for it on the web site. It uses an ARM v5TE architecture. 73 Eric ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
Re: [Discuss-gnuradio] Re: USRP2 startup
John Ackermann N8UR wrote: Hi Matt -- Got things built and usrp2_fft.py working (more or less). Just FYI, on my 3 year old Thinkpad T42 laptop with 1.6 GHz Pentium M, I can display about 4MHz of spectrum (decimate 25) with good results. Trying to show 5 MHz works, but occasional flakiness results. Anything beyond that causes either very jerky display, or lockup. Using nice -10 helps a bit. I don't know if this is consistent with what others have seen. Next step is to build on my Athlon X64 in the basement to see how that does. Hello, I have a Z60t with a 1.7 GHz Pentium M and found some overruns and occasional hiccups with the USRP1 at 8 MHz depending on what processing is done on the computer. 2. The usrp2_fft.py program is pretty nice, but changing the frequency in the input box doesn't seem to work -- when I type something in, I get an OK at the bottom left of the window, but the display freezes and nothing further happens. Matt mentioned at DCC that changing frequency does not work yet. 73 Eric ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
Re: [Discuss-gnuradio] Re: USRP2 startup
Matt Ettus wrote: John Ackermann N8UR wrote: Hi Matt -- Any hints for getting started? In particular, what needs to be done to talk to the usrp2 via the ethernet? The first step is to update to the latest svn for the entire gnuradio tree, and get it all installed. Then, run find_usrps in the usrp2/host/apps directory. You'll need to tell it which ethernet port to use if the USRP2 is not on eth0. I'm really interested in the spec analyzer you were running. Is that in the trunk? Are there other useful demo apps that have been moved to the usrp2? Run usrp2_fft.py, which is found in gr-utils and should also be installed in your path if you did a make install on the full tree. Matt Hello, Thanks for the information. The USRP2 arrived at work while I was on vacation in Romulus (MI, not the planet). I almost got in and out of work to fetch it without getting into anything work-related. I am still on vacation for the next few days but I am required to be the driver for a leaf peeping expedition and to herd some cats to the vet. I updated my local copy of the the trunk and noticed I do not have mb-gcc to build the USRP2 firmware. Are there currently firmware updates in the trunk that I need? Is there a compiled firmware image in the trunk somewhere? There does not seem to be a debian package for mb-gcc but I have not really searched. 73 Eric ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
Re: [Discuss-gnuradio] Re: USRP2 startup
Eric A. Cottrell wrote: There does not seem to be a debian package for mb-gcc but I have not really searched. Hello, I found the USRP2 faq was updated with firmware compile information. The AEMB soft processor (Microblaze clone) uses the Microblaze gcc tools and scripts provided by Xilinx. No Debian package available. I always wanted to create a tool chain. :) http://www.aeste.net/index.php?q=node/2 73 Eric ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
Re: [Discuss-gnuradio] Does any body has the source code and/or the algorithm for IMBE vocoder to decode P25 signals?
teka yemane wrote: Hi guys, Does any body has the source code and/or the algorithm for IMBE vocoder to decode P25 signals? I am doing a project on P25 software radio receiver and I need the IMBE vocoder source code. Thanks, Teka Yemane ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio Hello, In the P25 Training guide there is some information on the P25 frame structure. http://www.p25.com/resources/P25TrainingGuide.pdf When it describes the Voice Data (VC1 = VC9) in the frame on Page 48, the interleaving, error correcting, etc are done by the IMBE Codec. These are described in TIA-102.BABA. The current Codec chips decode and encode to baseband so it handles the whole stream. Chapter 7 gives some overview on how the Codec works. There are some other patents that describe IMBE used in other services and the error correcting techniques are similar. I like using the Patent Search in Google. Patent 5,805,612 Mechanism for repeater error mitigation Partial discussion of how the P25 voice frames are encoded. Patent 5,491,772 Methods for speech transmission The appendix describes the IMBE codec used in INMARSAT M. Different frame rate but the techniques are similar. If you search on IMBE in the Google Patent search there are many other patents. 73 Eric ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
Re: [Discuss-gnuradio] GNURadio compile notes for Debian Lenny (Testing)
Johnathan Corgan wrote: Eric Cottrell wrote: I was able to compile GNURadio on Debian Lenny. Here are some rough notes as to the packages needed to compile GNURadio with ALSA and USRP support. I used a recent GNURadio version from the subversion repository trunk. Just FYI--the Ubuntu binary packages for GNU Radio 3.1.3 hosted at gnuradio.org could be made to work with Debian Lenny with very few changes. I'd produce them here, but lack the infrastructure to do the build and test. They have been built on Etch in the past with no issues. The Debian package machinery in the trunk is fairly out of date, and needs to be updated. This is a task for release 3.2. I'll do this for Ubuntu, but it would be welcomed if someone would volunteer to test and produce the Debian Lenny packages. The needed repository infrastructure is already on gnuradio.org, but has no packages in it. Here is an (outdated) script in the trunk that installs the build dependencies: http://gnuradio.org/trac/browser/gnuradio/trunk/debian/install-build-deps.sh (It lacks new requirements for grc, for example, and the required boost version.) Anyway, if you or anyone else is interested in helping here, it would be a useful way to contribute to the project. Hello, I will be willing to help when I get setup and comfortable with the debian build system. I noticed gnuradio included in the debian archive but it is for one of the older releases of debian. Sometimes I wonder if I should use kbuntu instead of debian but I consider kbuntu and ubuntu more as live cd distributions. 73 Eric ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
[Discuss-gnuradio] Any GNURadio at the 2008 ARRL/TAPR DCC?
Hello, I am planning on going and bringing my USRP and a few radios and like stuff, like FT-817, 2 or 3 scanners, Icom 2500 with DStar/P25, WinRadio, antennas, cables, and splitters. I do not have any projects to show in the project room but would be willing to help show off GNURadio. I am also interested if any GNURadio users are planning on attending. 73 Eric ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
Re: [Discuss-gnuradio] Beagleboard
Philip Balister wrote: On Fri, Aug 1, 2008 at 6:31 PM, Eric Brombaugh [EMAIL PROTECTED] wrote: On Aug 1, 2008, at 1:58 PM, Philip Balister wrote: I've been talking to a friend (he knows FPGA stuff much better than me) about using the expansion port to communicate with an FPGA via a SDIO interface. I don't think we can beat the current USRP data rate, but we should be able to reduce the latency introduced by the USB interface. Looks like the SDIO ports run up to 50MHz and have 8-bit wide data. No idea how much overhead there is in that, but it might be able to go a bit faster than USB2.0 and as you note would have a lot less latency. Hook up to a decent FPGA and you could cram a bit of external pre-processing in as well. I picked up one of the Avnet Xilinx Spartan 3A boards for $50 that would probably work well for that. We are hoping to create a board with a reasonable FPGA that works with existing USRP daughterboards. This would make a really neat system for small SDR nodes. I'll be sure to keep you updated on out progress. Using an existing dev board for developing the beagle to FPGA interface is a really good idea, thanks for suggesting it! Philip Hello, Since I have some receive only applications I would like to see a box that took one RX or a RX/TX set of USRP daughterboard(s). The OMAP has some interesting interfaces and I wonder if some of them could be adapted for a more general I/O use. I am more familiar with the earlier versions of the OMAP. It will be nice to use the DSP for some signal blocks and use the ARM for more general UI and I/O blocks. 73 Eric ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
Re: [Discuss-gnuradio] Small Intel Based Computers for GNURadio
Eric Blossom wrote: On Mon, Jun 16, 2008 at 03:00:31PM -0400, Eric Cottrell wrote: Hello, I occasionally travel and want to take GNURadio with me. I wonder what laptops or small form factor systems (like ITX) work well with GNURadio. My current laptop, a Z60t, uses a 1.7 Pentium M. It is okay for most GNURadio apps but I get USRP overruns on other apps. My Core 2 Duo Desktop does better but it is too big. A Quad Core Laptop would be great but there seems to be only a few products based on Desktop Chips. I've been happy with a whole series of X* ThinkPads. Last I checked they're shipping with Core 2 Duos in them, which gives you a pretty serious 64-bit platform. I'd probably opt for a 7200 RPM drive and 2 GB of RAM. Hello, I looked at the T and X series and I may get a T. The new X61 with the dock does not look too bad. I looked at the X300 but it is targeted more for low power. I should hurry up or I will not be able to get one with Windows XP. The thing I keep forgetting about a luggable box is you likely need to lug a display, keyboard, and mouse as well. I still bought a new battery for the Z60t and while browsing decided to buy the new 1.6 GHz Intel Atom Motherboard and a Apex MI-100 mini-ITX case. Mainly to play with for a possible car computer but I will try GNURadio. I plan to load Debian on it. I came close to buying a PS3 for GNURadio use but it is not quite ready. I am happy with the Thinkpad series and use a 600e and a 600x for other radio stuff. It looks like the new series from Lenovo is the Ideapad. They can use the Thinkpad name only for a limited time and they want to give it up early. 73 Eric ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
[Discuss-gnuradio] Improving Mode-S/ADS-B demodulation using parallel detectors and blocks of samples
Thinking over the design of the Mode-S/ADS-B receiver I have a possible improvement. It changes the serial method of demodulation to a parallel block method. Mode-S/ADS-B is a smaller bandwidth signal in a wider bandwidth channel of 8 MHz. There is a frequency tolerance of +/- 1 MHz. Desired signals are from different sources and can overlap in time and frequency. There are also undesired signals (ATCRBS) that share the same channel and have a frequency tolerance of +/- 3 MHz. The incoming signal is oversampled at eight or ten MSPS. The recommended designs use serial processing and will only process one data transmission at a time. If two data transmissions overlap then the stronger one is selected and the weaker one is considered interfering. In one recommended design there is mention of using megabytes of ROM data to minimize the effect of the interfering signal on the selected signal. The interfering signal is likely at a different frequency so the ROM data is a lookup table based on the the effects of the interfering signal on the sample values. This process is done after the AM Detector. I assume a real ADS-B receiver has a single ADC that digitizes the output of a hardware AM Detector which would limit the possible methods. The USRP output is a complex signal. If I use the recommended designs then I am throwing information away by taking the magnitude of the complex signal and recreating the information later using the ROM lookup tables. I want to experiment with implementing multiple detectors across the channel. The detectors feed blocks of candidate samples to the Mode-S/ADS-B decoder. It seems to me that SNR improves by narrowing the detector bandwidth. The interference effect of multiple signals will be reduced as well. This may require a bit of processing power to implement. :) 73 Eric ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
Re: [Discuss-gnuradio] ask : USRP Mode-S/ADS-B project
Bino Oetomo wrote: Hello Eric A. Cottrell wrote: Hello, The code is still a work-in-progress. The hardware used, the USRP and DBSRX board, costs as much or slightly more than the RadarBox or SBS-1. It might be possible to do a simplified hardware board but I am not a hardware engineer. Mode-S/ADS-B has a 1 Megabit symbol rate which is way above what a sound card can do. Nice to hear that it's still in active stage. Obout the Receiver cost : I understand that, still ... ++ with this we can do some OpenSource and flexible solution ++ Hope ettus will consider to produce 1 port board. I reallize that the price cut will not that big ... since the core component (i.e : FPGA) still the same . but there is a cut anyway :) It would be likely be in the 500 dollar range as it would be similar to a RF Space SDR-IQ. It may be possible to optimize the design further so it will only decode Mode-S but that would preclude decoding the future UAT transmissions. The FAA plans to do TIS-B over UAT. TIS-B would provide information on Mode S and Mode A/C aircraft. There are some interesting hardware available or soon to be available that could reduce the coast. One interesting chip is the TI OMAP series that combines an processor and DSP on one chip. It may be possible to use one of the on-board devices to digitize the waveform but a RF front end is still needed. About Symbol rate : hmmm what about DVB rx card i'm not sure if we can customize their demodulation to handling mode-s/ads-b ... but they capable in handling up to 45 megabit/sec symbolrate , and capable of handling freq around 1 Ghz cmiiw. Arrrggh ... looks like we need to do firmware work (too many work). Thanks for your enlightment -bino- DVB receivers cover the same frequency range but are designed for larger signal levels from the LNB. DVB uses QPSK. Newer receivers have front end chips that take the RF and output the digital mpeg transport stream. The DVB Rx board for the USRP uses a DVB tuner chip but it is preceded by an amplifier. Some Video Cards do have an extra ADC that may be useful but you need more components for a complete system. Another avenue is alternate firmware for the SBS-1 or Radarbox much like the Rockbox project for MP3 players. I suspect that both units use soft microprocessors in the FPGAs. I try to keep track of hardware as does several others so if there is a lower cost solution it will be found. 73 Eric ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
Re: [Discuss-gnuradio] ask : USRP Mode-S/ADS-B project
Bino Oetomo wrote: Dear All I'm just searching about low cost ADS-B Receiver/Decoder solution. First, I found most people using SBS-1/RadarBox. They need to use propietary BaseStation software. But there is pio that looks like have a good progress on handling the output for linux and OS-x http://piopawlu.net/2008/04/15/sbs1-under-linux-and-mac-os-x/ And then I found GNU-Radio. I search the discussion archieve ... and looks like Eric have magic work on it. So .. how is the stage of this GNU-Radio USRP Mode-S project ? Is there any specific distribution for non technical people that just want to dumb decoded mode-s message to a console or pipe it to another program/script ? Regards -bino- Hello, The code is still a work-in-progress. The hardware used, the USRP and DBSRX board, costs as much or slightly more than the RadarBox or SBS-1. It might be possible to do a simplified hardware board but I am not a hardware engineer. Mode-S/ADS-B has a 1 Megabit symbol rate which is way above what a sound card can do. The code decodes to raw frames and the source is under my developer branch in the gnuradio repository. I need to convert it to use the new mblock scheme and to write some better output formatters and decoders. Mode-S and ADS-B are complex protocols. My 1090 antenna was down for the winter and I am planning on putting up a better antenna even higher after the snow melts and the weather gets better. 73 Eric ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
Re: [Discuss-gnuradio] Photo of the Beagle Board and USRP
Philip Balister wrote: I've received a Beagle board and started testing the USRP connection. (Still needs work) I've had several requests for more information so I thought a photo would help people understand the possibilities. http://www.flickr.com/photos/[EMAIL PROTECTED]/2439256116/ Philip Hello, The Beagle board looks interesting. I have looked at the OMAP 5912 processor. Is it available yet? The webpages I found indicate this is a future product. 73 Eric ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
Re: [Discuss-gnuradio] DV Dongle - AMBE USB Device
Gregory Maxwell wrote: On Mon, Mar 24, 2008 at 11:24 AM, Jeff Brower [EMAIL PROTECTED] wrote: [snip] Using a AMBE or other codec chip is part of the hardware versus software decision. We want to do everything in software but there are limitations. [snip] Agree. In the open source voice community, many times I see people try to cram something into software, even though they know it's would barely fit or likely would not. In some of the more flagrant cases I've seen, after spending great time and effort, the end result is poor voice quality (usually due to increased latency), unstable system that crashes or hangs easily, and code that is dependent on server characteristics. They're so determined to avoid a hardware solution they end up with no solution. You guys do realize that the 'hardware' AMBE solutions are just software running on a TI DSP, don't you? Hello, That is what I meant by peeking in the black box. :) Unlike filters or RF mixers wisely implemented in the analog domain for reasons of physics, dynamic range, and component availability AMBE is available only on chips in order to protect the ability of some to profit at the expense of freedom and flexibility for users of the technology. (I'm making no argument here about the ethics of limiting people's freedom in order to maximize profit, only pointing out the irrefutable fact it is being done. Being that this is *GNU*Radio perhaps I should be, however). Well, after being part of a weird process where my employer had to sign a NDA and get an account to access one small area of a company's site to look at one datasheet for a hardware chip my employer was considering, I think DVSI is reasonable in providing AMBE2000 documentation freely on their website even if it is marked confidential. Hardware companies should be in the business of providing hardware. Some companies feel that hiding how to interface to the hardware gives them a competitive advantage and it seems some companies go to extremes. I thought about the issues of including IMBE support in GNU Radio but did not think it would spark a lively discussion. I consider the other long-term GNURadio developers like EB to have a better handle on these issues. I just use and write GNURadio code as my hobby of learning about and building SDR. I think it is neat that when I have an interest in some digital mode I can code a receiver and learn some DSP techniques. So if it is decided not to include IMBE support in GNURadio then I will still likely write it for my own private use. On another note, I found some example ASCP source code for the RF Space SDR-14 that I can modify to use with the DV Dongle. I got off on the wrong foot on DV Dongle list but I got a surprise tonight of the AMBETest application posted to the web site. This is a good start but I may still need to write some of my own code. http://www.moetronix.com/files/ambetest103.zip If I modify the SDR-14 files to work on the DV Dongle and get a C++ API for my experiments then I plan to feed that back to the DV Dongle project. They need some example files if they expect software developers to use it for other modes. 73 Eric ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
Re: [Discuss-gnuradio] DV Dongle - AMBE USB Device
Hello, I got the DV Dongle friday and it seems to work. I downloaded an application to decode DStar on the computer but DStar is not very popular in the area yet. I have not decoded any DStar voice so far. I only did a AMBE loopback test. I got concerned because all the application software I downloaded on the dv dongle website was closed source with no mention of the open source firmware or GNU licenses. All the various voice rates in the test software are gone. It appears to be DStar only. There is a link on the dvdongle.com website pointing to the open source firmware project but the link does not mention firmware source. It is possible the makers locked out non-DStar voice rates before taking the product commercial. I asked on the DV Dongle Yahoo Groups list and it appears there is no developer's SDK. There is no documentation on using what appears to be a UDP to ascp daemon. A person replied to my query and said all IMBE rates are available. But given the events I wonder if anyone has tried other rates. It seems the makers are trying to make it difficult to use this device for non-DStar stuff. It also appears the company making the DV Dongle is violating the terms of the GNU License. None of the materials in the box or on the website mention it uses GNU tools and that source is available. There is a link to source code but the link description does not mention source code and it goes to another site. So it will likely be a week or so before I can test the device due to writing and debugging an ASCP driver. It looks like I am on my own in figuring it out using the provided documentation. 73 Eric ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
[Discuss-gnuradio] DV Dongle - AMBE USB Device
Hello, One of the problems with DStar and some other digital voice systems is the Patent and other IP considerations. DStar uses the AMBE codec which is owned by DVSI. Icom uses a DVSI AMBE2020 chip in their DStar products. One possible solution is to buy hardware that puts the Patent and IP into a chip. This increases the cost of the hardware and you need to interface it to the PC. Some chip makers do not make chip information available, but DVSI does. The USER Manual is very informative. http://www.dvsinc.com/products/a2000.htm A group was able to produce a USB Device that interfaces the AMBE2000 chip to the PC. The icing on the cake is it is an open source project. The API appears similar to the RF Space SDR products. http://www.moetronix.com/dvdongle/ The DV Dongle is now in production and even has a website, http://www.dvdongle.com/DV_Dongle/Home.html So I ordered one for $200 from HRO and hope to get it in a few days. It should be possible to add support for it in GNURadio. I am also thinking of writing a APCO P25 Voice to AMBE2000 frame converter and see if the device can decode P25 as well. This may be a general IMBE and AMBE codec. 73 Eric ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
Re: [Discuss-gnuradio] DV Dongle - AMBE USB Device
Rick Parrish wrote: Eric A. Cottrell wrote: I am also thinking of writing a APCO P25 Voice to AMBE2000 frame converter and see if the device can decode P25 as well. This may be a general IMBE and AMBE codec. I hope so. I looked at this a while back. What concerned me most was the AMBE2000/2020 documentation seemed to omit P25 style IMBE compatibility. Compare the docs to another DVSI product - the VC55 - to see what I mean. Hello, Looking over the docs the VC55 is a P25 only AMBE+ 2 CODEC that only supports full rate and the proposed (maybe part of standard now) half rate. What is good is the mention that the improvements are still compatible with the P25 vocoder standard. The AMBE + 2 part sounds like further improvements to the CODEC over the AMBE2000. The future AMBE3000 will implement AMBE + 2 and it appears compatible with the AMBE2000 and AMBE1000. The AMBE2000 is more flexible in the data rates and when I look at the rate tables on page 29 I see the P25 rate listed with the correct voice and FEC data rates. You can do the same rate in AMBE or AMBE+. So one task will be to figure out how to configure the chip so it will decode P25. 73 Eric ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
Re: [Discuss-gnuradio] GNU Radio wireless SmartMeters
Dave wrote: After years of development (involving close work with the EPRI, or Electric Power Research Institute, a power industry consortium of large utility corporations), PGE has selected a new type of electric power meter from SmartSynch, Inc. [2] that can wirelessly transmit massive amounts of data about your building's electrical usage to a radio receiver nearby in your neighborhood. From those base stations, the data is sent over an advanced communications network (meaning fractional T1?). Although PGE has no plan to utilize the device's real-time capabilities, the feature is nevertheless fully present in the beta devices... it is just not turned on, according to a semi-trained SmartMeter representative I spoke with, the feature is nevertheless fully present in the beta devices... it is just not turned on. Of course, we all know how terribly trustworthy and super-civic-minded these power companies are, right? Hello, A sizable utility like PGE needs a good data network for their SCADA system. This is used for distributed metering and control at the transmission line level and employs Microwave and/or Fiber. The Fiber is usually run along the transmission line right-of-way. Utilites usually own and maintain their communications networks. http://en.wikipedia.org/wiki/SCADA Power Line Carrier is used for low speed data. It is basically Low Frequency Radio Waves coupled directly to the transmission line. Older systems used on-off keying while newer systems use PSK. http://en.wikipedia.org/wiki/Power_line_communication A brief search shows PGE uses fiber and offers their excess capacity for sale as some other utilities are doing. Some utilities are also looking into becoming ISPs by deploying a Broadband over power lines (BPL) system,. From what I heard about SmartMeters they extend SCADA functions down to the distribution level. I could see utiliies having the wireless receivers at substations and using their fiber to get it back to the central servers. I mainly deal with the Protective Relaying part of the industry so I am more familiar with electric utility communications that support the System Fault Protection part. The few large utilities I have talked to do take network security seriously. The security threat posed to you in your home depends on what is meant by real-time. Typically the meter in a house measures the power you use in watt-hours. The real-time function may just be a direct reading of the voltage and current on a per cycle basis much like a regular AC Voltmeter and AC Ampmeter. I would be more concerned if the device has DFR (Digital Fault Recorder) functions that can sample many points on the AC waveform and send it back over SCADA. The sampling rates generally go up to 200 KSPS. http://preview.ametek.com/content-manager/files/pip/2100736.pdf I am not familiar with the sampling rates needed to reconstruct computer monitor output. A DFR is handy if a transmission line fault occurs and the fault protection does not operate properly. It is possible to playback the fault recording from the DFR records and test the fault protection. I work for a company that makes test equipment for the power industry. It is a private company in the process of being sold to the holding company that owns DCSI. DCSI is involved with SmartMeters. http://tdworld.com/customer_service/power_smartmeter_program_deployment_2/ 73 Eric ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
Re: [Discuss-gnuradio] Typo on UdevConfig page in wiki?
Eric Blossom wrote: On Sat, Nov 10, 2007 at 08:41:24PM -0500, Eric A. Cottrell wrote: Hello, I finally got my main computer fixed, hardware upgraded, and OpenSuSE 10.3 installed. I noticed going through the wiki instructions when installing gnuradio in 10.2 and now 10.3 that one command maybe wrong at http://gnuradio.org/trac/wiki/UdevConfig. Currently it is: Add a user to the group # /usr/sbin/usermod -a usrp [username] If your copy of usermod does not support this syntax try # /usr/sbin/usermod -G usrp -a [username] It appears that the -a should not be included in the second command line. When I used the form below it added [username] to the usrp group. I think the wiki needs to be corrected but I am not 100% sure. If your copy of usermod does not support this syntax try # /usr/sbin/usermod -G usrp [username] 73 Eric Not sure. Check it out, and please fix it on the wiki. FWIW, I just edit /etc/group with emacs ;) Eric Hello, I did research and for Redhat/Fedora based distributions the -a is needed. The -a means append and without it a user would only be a member of the usrp group. So I will add some more information to make it clearer. 73 Eric ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
[Discuss-gnuradio] OpenSuSE 10.3 notes
Hello, Some general stuff I think needs to be updated in the wiki. Python-numpy is used for current versions instead of python-numeric. Also guile is needed to compile mblock and pmt. usrp needs mblock. I will do some research and update the wiki. Building Under Opensuse 10.3 Cppunit-devel is named libcppunit-devel in opensuse 10.3. SDCC packages can be found on the opensuse build service under Home:/illuusio/ so it is easier for suse users. PS3 Development Fedora seems to be the hot distribution for PS3 Linux and likely has the cutting edge development. I noticed that opensuse has the gnu cell tools and the cell cross-compile tools. It is also possible to install Suse on the PS3. I do not have a PS3 so I can not compare it. 73 Eric ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
Re: [Discuss-gnuradio] OpenSuSE 10.3 notes
Eric Blossom wrote: On Sun, Nov 11, 2007 at 11:48:55AM -0500, Eric A. Cottrell wrote: Hello, Some general stuff I think needs to be updated in the wiki. Python-numpy is used for current versions instead of python-numeric. Also guile is needed to compile mblock and pmt. usrp needs mblock. I will do some research and update the wiki. Great, thanks! PS3 Development Fedora seems to be the hot distribution for PS3 Linux and likely has the cutting edge development. I noticed that opensuse has the gnu cell tools and the cell cross-compile tools. It is also possible to install Suse on the PS3. I do not have a PS3 so I can not compare it. Cool. Can you point me at a repo or web site? Thanks, Eric Hello, The main site for opensuse. You can bittorrent the isos. http://www.opensuse.org/ The site has a PS3 install page at http://en.opensuse.org/PS3 The iso images tend not to have all the available packages so you need to use the repo. I modified a WD MyBook World Edition to be my personal repo and update mirror since I have several computers running opensuse. The Linux in the WD box included ssh and rsync so I rsync updates to the WD. My favorite mirror site (has rsync as well). ftp://mirrors.kernel.org/opensuse/distribution/10.3 The opensuse website lists other mirrors. The cross compile packages I see for Cell SPU processors cross-spu-binutils Version 2.17.50.20070726 cross-spu-gcc4.3.0 cross-spu-gcc-static 4.3.0 cross-spu-newlib 1.15.0 There maybe updated versions or other ps3 packages through the opensuse build service. 73 Eric ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
[Discuss-gnuradio] Typo on UdevConfig page in wiki?
Hello, I finally got my main computer fixed, hardware upgraded, and OpenSuSE 10.3 installed. I noticed going through the wiki instructions when installing gnuradio in 10.2 and now 10.3 that one command maybe wrong at http://gnuradio.org/trac/wiki/UdevConfig. Currently it is: Add a user to the group # /usr/sbin/usermod -a usrp [username] If your copy of usermod does not support this syntax try # /usr/sbin/usermod -G usrp -a [username] It appears that the -a should not be included in the second command line. When I used the form below it added [username] to the usrp group. I think the wiki needs to be corrected but I am not 100% sure. If your copy of usermod does not support this syntax try # /usr/sbin/usermod -G usrp [username] 73 Eric ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
[Discuss-gnuradio] PS3 and OpenSuSE 10.3
Hello, I noticed today that OpenSuSE 10.3 is just released so I browsed around. I will be upgrading to 10.3 in a few days after download. I am interested in the PS3 as well so I thought it was great that it is directly PS3 installable. http://en.opensuse.org/PS3 I remember some comments that Python appears to be broken on the PS3 and wonder if the Version 2.5.1 packages in 10.3 would address some of the problems? 73 Eric (insert letter after B here) ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
Re: [Discuss-gnuradio] Mode S and ADS-B
Tom O wrote: Hi Eric, When I run usrp_mode_s_logfile.py I get: ImportError: cannot import name air Can you help me out? Tom Hello, air is the name of the python library that contains the gr-air blocks. Make sure you compiled and installed gnuradio properly and have PYTHONPATH set correctly. There should be several _air.* and air.* files in site-packages/gnuradio (typically /usr/lib/pythonversion/site-packages/gnuradio or /usr/local/lib/pythonversion/site-packages/gnuradio). The default prefix for compile is /usr/local so you may have to add subdirectories under the /usr/local directory to various paths. 73 Eric ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
Re: [Discuss-gnuradio] Mode S and ADS-B
Matt Ettus wrote: Eric A. Cottrell wrote One thing to try is to use the scope program to set the threshold. The default is low for alot of front ends including the DBSRX. The DBSRX tends to be deaf. Also I find a gain setting of 32 to 36 seems to work best for the DBSRX. The DBSRX typically has a noise figure around 3-5dB. I wouldn't call that deaf. You are connecting a discone to a wide open front end without a filter, so it is far more likely that you are experiencing desense from the thousands of other signals you are picking up. Also, raising the gain above 32 would reduce the noise figure you see. Getting the antenna up in the clear is important. A discone will work if you have a good receiver but I found building a simple 1/4 wave ground plane on an N connector beats out the discone. Hello, Well I got spoiled with my AOR 5000 as a front end. It uses a GAs MES FET as a front end for 1.0 to 1.6 GHz. Unfortunely the GAs MES FET is not working but it only cuts the range in half. I was using an external Preamp but that got broken when I hooked it up in the car. I assume when they say 12 volts that they mean 12 volts and not over 13.6 volts. I tended to use 36 as gain for the DBSRX. I used my DBSRX board yesterday and got different results from earlier tests. It appears the Maxium chip is working but the LNA is gone. Time to order another one. Probably because it is more frequency selective than the discone, thus reducing the strong interferers. When you set up a discone on the DBSRX you need to understand that you are picking up multiple cellphone bands, the pager bands, 2 ISM bands, microwave ovens, radars, etc, in addition to the nice weak signals you are looking for. Not to mention the decrease of gain from the discone. Another factor at my station is my discone is lower and has more blockage. I need to replace the coax at my test antenna site because the N connector came off and the coax got exposed to the rain. I am upset because I want to test my code to make sure my later changes did not break anything but hardware keep breaking! So it may be possible the code in my branch does not work as good as past code. I want to do some testing of various setups but I need to get everything working again. :( 73 Eric ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
Re: [Discuss-gnuradio] Mode S and ADS-B
Martin Dvh wrote: Hi Eric, I tried out your code. Does it run on your machine in realtime? Yes. It works quite well on my Core 2 Duo. I have a dual-core athlon X2 3800 and both processor go to 100 % when I run it. (I didn't know gnuradio could use both processors , I though we still had the single-threaded-scheduler) This gives me a lot of USRP overruns (UoUoUo) so it doesn't work very well this way. Does mode-s really need a samplerate of 800 The methods I used to implement the code do require 800 and that is the slower rate with 1000 the preferred rate. I may be wasting some CPU cycles. One thing to try is to use the scope program to set the threshold. The default is low for alot of front ends including the DBSRX. The DBSRX tends to be deaf. Also I find a gain setting of 32 to 36 seems to work best for the DBSRX. If the threshold is set too low I find that so much data is being processed that even my Core 2 Duo will start UoUoUo a little. I set the threshold so that most of the noise is below the threshold value. Try a gain of 32 and a threshold of 75 to start. If you set the scope to sync on channel 2 going negative you should see Mode Select frames of various amplitudes. Getting the antenna up in the clear is important. A discone will work if you have a good receiver but I found building a simple 1/4 wave ground plane on an N connector beats out the discone. I had good results using my AOR 5000 as a front end. I used the wideband IF output through a 20 dB amplifier to the LFRX board. I have tried other receivers with tapped IF outputs and did not get good results. I think it is the combination of the low noise front end of the AOR 5000 and being able to turn off AGC. I am experimenting with antennas and want to find a GAsFet preamp that covers the band here in the US. Another question. I know 1090 Mhz is the frequency they use in the US. I googled for info on frequencies for mode-s and ads-b and it seems multiple frequencies could be used. Does anyone know of an overview of the actual frequencies in use, at which places. (I live in the netherlands) 1090 MHz is the international frequency. You may be thinking about UAT for smaller private aircraft. 73 Eric ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
[Discuss-gnuradio] Mode S and ADS-B
Hello, I finally checked in the infamous Mode Select code to branches/developers/wb1hbu/wip and I am glad this portion is done. I spent a couple of days cleaning the code up a little. I also added some features. Likely I missed using a few neat gnuradio functions. There is a usrp_oscope_ms.py program that displays the Mode Select signal, Reference Level, and Attributes. Triggering off of channel 2 (Reference Level) allows the display of Mode Select waveforms. I made the attributes go negative so they are more visible. I was surprised at the results. The usrp_mode_s_logfile.py program outputs Mode Select frame information to a log file. It does no decoding of the data. It logs the data bits and other attributes of the signal and error correction. It is a good program to run if you are in a heavy air traffic area and want to generate megabytes of text within an hour. 73 Eric ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
[Discuss-gnuradio] D'oh!
Hello, Well my first commit and I fell flat on my face. I committed the source directory for the Mode Select code but not the actual source files. This is fixed. I am using the kdesvn tool which seems to work good once you figure out the difference between the add and the add recursive commands. :) I need to adjust the padding of a structure to eliminate buffer warnings. I noticed that sometimes it occurs on only one of several machines I use. It seems like sometimes I make changes and I do not get the buffer warnings until I do a make distclean then do a build. The code will mot be merged into the trunk for awhile as I still need to add things and fix things. I notice some problems with the good frame only filter in the log formatter. I do not seem to get good short frames other than type 11 from ACAS/TCAS interrogators. 73 Eric ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
Re: [Discuss-gnuradio] D'oh!
Matt Ettus wrote: I need to adjust the padding of a structure to eliminate buffer warnings. There really isn't any need to get rid of the warnings unless you find that it is a big performance hit, which is VERY unlikely. I noticed that sometimes it occurs on only one of several machines I use. It seems like sometimes I make changes and I do not get the buffer warnings until I do a make distclean then do a build. This, on the other hand, is a problem. You should get the same messages every time you run. Matt Hello, I will look at it more. Meanwhile I think my DBSRX board broke. I can not receive anything and the Maxium chip gets pretty warm. The +5 Volt line at the electrolytic cap measures 4.88 volts with 6.14 volt input at the power socket. Any other points I can check? 73 Eric ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
Re: [Discuss-gnuradio] Question regarding the DBSRX frequency range and bandwidth
Matt Ettus wrote: Bandwidth: When Maxim states that their maximum LPF bandwidth is 33 MHz, they mean one-sided bandwidth (i.e. 0 to 33 MHz). Since it is used in a direct conversion IQ system, that actually gives a 66 MHz bandwidth (-33 MHz to +33 MHz). Since that is beyond nyquist for our ADC, I spec to 60 MHz (+/- 30 MHz). On the low end, they specify 4 MHz, which is really 8 MHz (+/-4 MHz) of RF bandwidth. The filter is actually capable of going to a much narrow frequency, but it is outside of Maxim's specs, since nobody in the small satellite dish market cares about less than 8 MHz of BW. So I spec that it goes down to 1 MHz wide. It should be noted that when you go below 4 MHz wide (2 MHz in Maxim-speak) that your noise floor will rise a bit and phase noise may also rise. Matt Hello, I assume the parameter for the setbw function is the double-sided bandwidth and not Maxim-speak? 73 Eric ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
[Discuss-gnuradio] Mode-S and ADS-B
Hello, Some people may think that I have lost interest and dropped this project. Neigh, Neigh as Mr Ed would say. It just took some time because of illness, business trips, having to rethink the implementation. The receiver now sends signal attributes along with the sample and each block adds it's piece. I looked at the OFDM stuff, but it was really the ATSC code that gave me some good ideas. So the receiver will output mode-s frame classes using a queue. It also outputs signal strength (reference level) and timestamp of the lead pulse (sample count). The receiver seems to work better. I implemented the improved multiple sample technique for decoding the PPM data bits and gained about 20 to 30 miles of range. With the 1/4 wave groundplane and the AR5000 frontend I can get up to 150 miles and sometimes more. Most of the articles I read talk about techniques to improve reception. It will be interesting to see how this receiver compares to other receivers. The next part is the Parity and Error Correction blocks. The information I have is somewhat confusing, but Error Correction Codes are not my strong suit. It's a Galois Field, Captain! :) There is a conservative approach correction that can correct up to 12 bits in a single 24 bit window if all the bits need to be complemented. There is a brute force approach that can correct up to 5 bits by flipping the low confidence bits and seeing if the crc syndrome goes to zero. This only works for ACAS and ADS-B frames as other frames have data like the airframe address overlayed on the parity. I am planing on putting quality information in the mode s frame class based on the confidence level and if the frame needed correction. I also want to get rid of some magic numbers so I can run the receiver at different sampling rates. Right now it will only work at 8 MSPS. I did implement some calculations based on the sample rate but the descriptions I have read give a few magic numbers. Now the code is getting stable I will be putting it into my branch in SVN by Sunday and start to polish it up. 73 Eric ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
Re: [Discuss-gnuradio] attribute/control stream question
Tom Rondeau wrote: Matt Ettus wrote: Eric A. Cottrell wrote: Hello, The processing of pulses into data requires me to keep track of valid pulses (following samples are above threshold) and leading edges (sample is 6 dB or more than previous sample and following sample is 6 dB or less than current sample). I also want to indicate preamble start and pass timestamps along. I have thought of three methods to do this but do not know which would be the best one. You can do this, or you may be able to break things up into chunks of samples and process them as vectors. See the ofdm_sync code for an example of how we do that. Also, off the top of my head, you might find the peak_detector and sample_and_hold blocks useful for what you're doing. If these won't do what you need, that at least the S/H block illustrates the use of different streams where input stream 0 is some data type (float, gr_complex, bytes, ints) and input stream 1 is a byte stream (sizeof_char) as the control line. Tom Hello, Thanks for the suggestions and observations. I will look at the OFDM code and other blocks. This is getting to be a big project. PPM is so simple but there are some interesting enhanced receiving techniques to squeeze the last drop of performance. I took a text description and turned it into code so no doubt there are other functions I can use to optimize the current code. I want to add capability to time stamp the frames and get signal levels so I am modifying the code again. I also want to comment it so others can figure out what is going on. Sorry it is taking some time to get the code ready but I want the code structure to be set before check-in. I am still figuring out GNURadio and Python so I looked at the cfile example and used it to improve my log program. I noticed that I may be able to use a higher sample rate if I go with the 4rx0tx USRP file. A future enhancement may be to put the AM detector in the USRP and just send shorts over the USB bus. I want to try 10 or 16 MSPS rate to see if performance improves. I want to try the OFDM code anyway and see if I get any data off the BPSK carriers of IBOC AM stations used for station information. 73 Eric ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
[Discuss-gnuradio] attribute/control stream question
Hello, The processing of pulses into data requires me to keep track of valid pulses (following samples are above threshold) and leading edges (sample is 6 dB or more than previous sample and following sample is 6 dB or less than current sample). I also want to indicate preamble start and pass timestamps along. I have thought of three methods to do this but do not know which would be the best one. The first method is to have two streams through the blocks, one a float stream containing the sample values and the other a short or int stream containing the attributes and control. The float data makes it easier to do processing as some of the blocks use 3 dB multiplication of the samples (1.414 and 0.707). Being an old programmer I still have the float equals slow performance mindset. The second method is to have the two streams as shorts. I have to deal with an integer multiplication and division (sample * 707 / 1000). I have no handle if integers would be faster than floats other than integer division tends to be expensive. The third method is to use one integer stream and have the upper 16 bits be the attributes/control and the lower 16 bits be the value. This method has an additional minor disadvantage over the second method of needing to mask off the upper 16 bits when using the value but I do not have to deal with two streams. 73 Eric ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
Re: [Discuss-gnuradio] DAB, RDS, DRM, HDradio and OFDM
Matt Ettus wrote: Martin Dvh wrote: Hi all, Is anybody working on DAB, RDS,DRM, HDradio or OFDM at the moment. Actually, Tom, Eric, George, Thibaud, Bob, and myself are all at Virginia Tech this week, and we're working on OFDM. We just checked in some working OFDM code in the trunk. You can play with benchmark_ofdm.py in gnuradio-examples/python/ofdm Work continues of course, but there is plenty there to play with. Matt Hello, I was following the commit activity as I am learning SVN. I do not want to be drummed out of GNURadio for destroying a repository :). I spent the week down in Chattanooga on a business trip. Last time I drove from Boston so I went near VT on I-81. This time I went by train so I was over near Danville/Lynchburg area. I usually take some vacation along with my trips but this one was a vacation just on the train. I did not do as much radio listening or USRP work on this trip as I planned. Since the train goes near Newark Airport I was trying to capture some TIS-B frames. One advantage of a train over a airplane is I can sit there in Business Class with my laptop, a USRP box, and a 1090 MHz Ground Plane without being bothered. I did not log any TIS-B. :( After I get the Mode Select stuff checked in, I want to look at the OFDM code and see if I can figure out some AM IBOC. 73 Eric ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
Re: [Discuss-gnuradio] DAB, RDS, DRM, HDradio and OFDM
Martin Dvh wrote: Hi all, Is anybody working on DAB, RDS,DRM, HDradio or OFDM at the moment. I will probably be working on all of these in the near future and was wondering what the status is of these and where to find what. Hello, I have some interest in IBOC. iBiquity has some information on the waveforms used. Maybe a person like Bob can figure out the parameters. http://www.ibiquity.com/i/pdfs/Waveforms_AM.pdf http://www.ibiquity.com/i/pdfs/Waveforms_FM.pdf The AM waveform seems a lot simpler to tackle. The real fun will be figuring out the data formats. I assume that an IBOC receiver first locks on the IDS data stream, or maybe a Reference since it is BPSK modulated. I have seen weak signals where a IBOC receiver can get the call but can not go into full IBOC mode. This makes me suspect that you could receive the callsign without using OFDM. After it gets the service mode it then configures the receiver for OFDM. I was thinking of doing a receiver that phase-locks to the AM carrier so I can look at the I/Q output of a IBOC signal. You can also use it as the basis for a AM Stereo radio receiver. 73 Eric ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
Re: [Discuss-gnuradio] End-to-end delay question
Steve Bunch wrote: What I noticed eventually by accident was that the beagled background process, which is enabled by default in Fedora Core 6, kicks in when the console of the Linux box goes idle for a while (screen saver kicks in), and wants to consume 100% of CPU time to index my files. The CPU scheduling interference with GNURadio, due to the default time-sharing scheduling regime both were running under, was causing the audio sinking to get behind. Turning off the beagled default startup has made the overrun problem disappear. (As would running GNUradio with RT scheduling priority, which I'd be doing in production use.) Hello, This may explain some weird behavior I saw with USRP input overruns suddenly occuring several minutes after the start of a GNURadio program. Thanks. 73 Eric ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
Re: [Discuss-gnuradio] Dayton
Matt Ettus wrote: Chris Stankevitz wrote: Matt Ettus wrote: Unfortunately, I had to cancel my trip to Dayton at the last minute. Ettus Research will not be represented there this year, but we hope to be back next year. What's going on in Dayton? The Dayton Hamvention, see hamvention.org Hello, I usually go to Dayton every 2 to 4 years but may go next year to say hello to other list members. Being an AMSAT guy I got to talk to Bob, N4HY, who asked when I was going to check-in to SVN. :) It is easy to forget there are non-HAMs on this list. Being a ham it is easy to consider Hamvention since it covers many of my interests. For someone interested in SDR there are a few vendors and a couple of forums. TAPR is involved in the HPSDR project. Things are mainly Amateur Radio oriented. Most of the vendors are Amateur Radio oriented but there are some rf parts and computer vendors as well. The fleamarket again has mostly Amateur Radio stuff but you can find all kinds of electronics and non-electronics items. Over 10,000 people attend and fill up the hotels around Dayton. I got to stock up on various SMA adapters for the USRP that I could not find locally. I got some 800 MHz NMO antennas cheap to modify for 1090 MHz use. I bought a wideband preamp and somehow a WinRadio WR-G305e receiver followed me home. Look for my radio museum to open in 2011. :) 73 Eric ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
Re: [Discuss-gnuradio] Mobile Power Supply for USRP
Hello, I went to the local electronics store and got a 2 Ampere Car Adapter. http://www.velleman.be/fr/en/product/view/?id=350662 I tried it last night and it seems to work. I was able to use the USRP in the car with my laptop. I may get something bigger at Dayton since I have a number of mobile devices that need 6 volts. 73 Eric ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
Re: [Discuss-gnuradio] Re: Mode S and ADS-B
Boris Maryshev wrote: Great news indeed, but still no code in svn? Hello, I am planning post-Dayton for svn. Things are not complete. I got some panel mount N connectors and made up a simple 1/4 wave groundplane for 1090 MHz. I tie-wrapped a 40 foot or so extending tent pole to my back deck and was able to go 10 feet above the Discone. The 1/4 wave on the pole added about 20 miles of range over the Discone. I also tried my AOR 5000 with the out-board IF Output amplifier into the LFRX daughterboard and was able to get about 100 mile range on the discone and 120 mile range on the 1/4 wave. I also got some surface position reports from Logan. With Google Earth most of the surface positions were located on Runways. One was in a East Boston neighborhood but it is likely due to INS errors. Most planes takeoff down the centerline of the runway but some are way off. Instead of getting ready for the Dayton trip, I spent yesterday evening using NEC to make a curly coil colinear with 1/4 wave and 5/8 wave elements. I have not built it yet. I implemented the new preamble detection and it works better. I need to do the bit error detect and correction part. I thought I was getting a lot of bit errors on some messages. I reread my background information and found the interrogator id is XOR with the CRC. On other messages the airframe id is XOR with the CRC. Reminds me of RDS used on the FM broadcast band. The ADS-B and ACAS messages have an interrogator id of zero so they are easier to check. I did a quick check of the file generated using the AOR 5000 with the 1/4 wave antenna and found all 15 possible interrogator ids in use. I looked at the all-call replies of a few aircraft and it was not unusual for the transponder to respond to multiple radars. Because I have interest in doing other aircraft receivers, I am thinking of calling the project directory gr_air. I was also thinking about gr_aero but people may mistake it for the Windows Vista video sink. Mode S has a different meaning for the AMSAT crowd so it is not a good choice. 73 Eric ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
Re: [Discuss-gnuradio] Problem using usrp_fft.py in Suse 10.2 64 bit.
Eric A. Cottrell wrote: Hello, I got my new Core 2 Duo system up and running with GNURadio. When I installed Suse 10.2 64 bit I also selected install the 32 bit packages. My Mode S code works and usrp oscilloscope work but when I run the usrp_fft.py I get a constant error message and no display. The error is in line 276 of fftsink.py with the call to Numeric.concatenate. The error message is: ValueError: matrices are not aligned for copy. I noticed the path is /usr/local/lib64/python2.5/site-packages/gnuradio/wxgui/fftsink.py Is this a problem with using 64 bit python versus 32 bit python? Hello, Some more information. When I setup my Core 2 Duo system I got GNURadio code from the main trunk. The laptop was using an older version of the main trunk and did not have a problem. A couple of days ago I updated the laptop from the current main trunk and now I get the same problem with fft. I also find problems with oscilloscope on both systems if I select certain timebase entries. I suspect a recent change caused this and likely the example code needs to be updated. I may look at it over the next few days in my hotel room to kill time. 73 Eric ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
[Discuss-gnuradio] SDR at Dayton Hamvention
Hello, I am attending Dayton this year and it is good that I will not miss out on learning more about SDR. I plan on bringing a good portion of my listening shack, including my USRP, to monitor Radio Communications in the area. :) My hotel is around 12 miles from Dayton International so maybe I can pickup some 1090 MHz transmissions. The fun will be waking up early to attend the sessions. From http://www.hamvention.org Friday Room 2 9:00 a.m. - 10:45 a.m. TAPR Digital Moderator: David Toth, VE3GYQ Speakers:John Ackermann. N8UR; TAPR Open Hardware Licence Steve Bible, N7HPR; Scott Cowling, WA2DFI; HPSDR Update John Ackermann,N8UR: Timing Projects Matt Ettus, N2MJI; GNURadio Saturday Room 1 8:00 a.m. - 11:00 a.m. Software Defined Radios Open Source Software Defined Radios- the new wave in radio communications. The Future of radio is NOW and is moving forward at the speed of light! Amateur radio operators are at the forefront of a technical revolution in radio. In the foreseeable future, everyone will be able to configure the ‘front panel’ of a, radio, spectrum analyzer, VNA, oscilloscope, signal generator and more, all with the same hardware! Groundswell open source amateur offerings of hardware and software ranging in price from $29 to several hundreds of dollars are available. Come see what this International excitement is all about, and win a Software Defined Radio! (Must be present to win at end of presentations.) Moderator: Eric Ellison,AA4SW Speakers: Lyle Johnson, KK7P; Introduction to the HPSDR-High Performance Software Defined Radio Project. Phil Harman,VK6APH, A Simple Approach to Learning Digital Signal Processing. Jonathan Naylor,ON/G4KLZ; The µWave SDR Hardware and Software. Alex Shovkoplyas,VE3NEA; Rocky, a View From Inside and Out. 73 Eric ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
[Discuss-gnuradio] Mobile Power Supply for USRP
Hello, Is there a off-the-shelf product to power the USRP from 13.8 volts? My understanding is the USRP needs a couple of amperes at 6 volts. The best I saw was 1 Ampere maximum output. 73 Eric ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
[Discuss-gnuradio] Problem using usrp_fft.py in Suse 10.2 64 bit.
Hello, I got my new Core 2 Duo system up and running with GNURadio. When I installed Suse 10.2 64 bit I also selected install the 32 bit packages. My Mode S code works and usrp oscilloscope work but when I run the usrp_fft.py I get a constant error message and no display. The error is in line 276 of fftsink.py with the call to Numeric.concatenate. The error message is: ValueError: matrices are not aligned for copy. I noticed the path is /usr/local/lib64/python2.5/site-packages/gnuradio/wxgui/fftsink.py Is this a problem with using 64 bit python versus 32 bit python? 73 Eric ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
Re: [Discuss-gnuradio] Re: Mode S and ADS-B
Martin Dvh wrote: Cory Papenfuss wrote: I have a digital-wip branche which is work in progress for digital QAM stuff and general-wip which is my work in progress for general gnuradio things (latest addition is gr-cxadc, a driver for cx2388x capture cards to use as a general purpose high-speed ADC frontend as a cheap alternative for an USRP) Greetings, Martin Has there been some progress on that front then? I've been lurking here for awhile, but last time I looked into this I don't think the TV -capture cards were viable. The BT8xx chips still have holes in the data, right? CX2388x can stream baseband without VBI holes? Yes they can. Look in the mailinglist for TV card SDR: http://lists.gnu.org/archive/html/discuss-gnuradio/2007-04/msg00134.html http://lists.gnu.org/archive/html/discuss-gnuradio/2007-04/msg00042.html How Chee page on this: http://www.geocities.com/how_chee/cx23881fc6.htm My page on this: http://www.olifantasia.com/projects/gnuradio/mdvh/cx2388x/cxadc/ SVN files are in http://gnuradio.org/trac/browser/gnuradio/branches/developers/nldudok1/general-wip cxadc is the kernel driver gr-cxadc is the gnuradio driver/glue gnuradio-examples/cxadc are the example scripts Hello, What are the sampling rates for these cards? Can they go up to 8 or 10 MSPS? If so I might be able to try them out with Mode S. 73 Eric ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
[Discuss-gnuradio] Re: Mode S and ADS-B
Hello, I am making good progress. The first couple of weeks or so (months?) I was collecting information. I managed to get some design articles about Mode S transponders, various protocol specifications, and comments. I was able to decode some packets by sight using the oscilloscope program. The bit timing is very tight. Thanks go to Matt Ettus for designing a board that can handle a 4 MSPS sampling rate. It was now coding time! I reviewed some GNURadio design guidelines and how to write a module. Of course the name is most important. I decided on a subdirectory off gnuradio named gr-mode-s. gr-transponder would make it look like sending as well as receiving. My project is focused on Mode S data and derivatives (TCAS, ACAS, ADS-B, TIS-B, etc). I am open to a better name as the mode-s name forced me to use the prefix of mode_s for things. I decided to use gr-pager as the model as it is the closest to what I want to do. I eliminated some blocks but may put them back in. I basically have a slicer, decoder/framer, and parser C++ blocks. I use python code to put the blocks together into a mode S decoder superblock. I appreciate the autoconf/automake and the whole gnuradio build scheme. For a programmer who has only done small gcc projects it looks like it is real work to do things from scratch. I was able to figure out what most of the autoconf/automake files are for. I replaced the pager prefixes with mode_s, add the required .m4 files, etc. I was amazed that I got my new project integrated into the build tree quickly. The major part of the time was spent getting my code to work. So I am jumping up and down with joy as I can now decode Mode S. I can now work on improving the slicer, add decoding of the messages, etc. It seems like I am not getting hundreds of miles of range due to the antenna setup but I get enough to work on the decoders. A future to-do is to submit my code. I guess I need to join the patch list. It would be neat if I could get hardware that is smaller sized. Maybe a USRP Jr board that allows one receiver or one receiver and one transmitter board, I could also use one with a LFRX board and dedicate it to my AR5000. 73 Eric ___ Discuss-gnuradio mailing list [EMAIL PROTECTED] http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
Re: [Discuss-gnuradio] lfrx+loop antenna
konvak wrote: hello all, I am thinking about building loop antenna for 3-6 MHz to receive some DRM stations. As I understand it the loop antenna is parallel resonant circuit so without any amplifier the parallel res. circuit should look into big impedance(~1 MOhm) to get high Q. Lfrx has 50 Ohm input due to the resistor at diff. amplifier. My question is, would it be possible to remove this resistor and put there 1MOhm and connect it to the loop antenna with coax. Would it work? thank you for any suggestions and help, tomas Hello, I have seen both buffer amplifiers and toroidal transformers used for loops. Be aware that loops have low signal output compared to other antennas and the signal advantage is the noise pickup is lower (higher S/N rather than higher output. So some gain is needed to connected it to the Lfrx. I had good sucess with a KAZ antenna, which is a triangle that is 40 feet long and 10 feet high. It uses a 9:1 toroid matching transformer. It is meant for LW and MW but seems to be okay for low HF. I used my usrp connected up to the 10.7 output of a receiver rather than connected directly to the antenna. 73 Eric ___ Discuss-gnuradio mailing list [EMAIL PROTECTED] http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
[Discuss-gnuradio] doxygen build problem
Hello, When I build the doxygen documentation, both the GNURadio and USRP documentation are built. The problem is both are installed in /usr/local/share/doc/gnuradio-3.0svn/html/ and the USRP index file overwrites the GNURadio index file. Other files are likely trashed as well. I would like to have both sets of documentation. Is this a bug or do I need to configure something differently? 73 Eric ___ Discuss-gnuradio mailing list [EMAIL PROTECTED] http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
Re: [Discuss-gnuradio] USRP 4 Questions
Weber, Michael J. (US SSA) wrote: Eric, I also recently received some enclosures... this is my two cents, YMMV, etc: If the fan is installed such that it blows in onto the USRP, it will receive the direct benefit of the airflow. However, the fan makes a lot of noise in this configuration because the blades are right next to the perforated enclosure wall. Hello, I got some fuses from Mouser so I am all set. The only unanswered part is where do you hook the fan up to? Does the USRP 4 have the holes for a connector or is it cut the fan connector off and wire direct to the board? 73 Eric ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
[Discuss-gnuradio] Have USRP, will travel to SWL Fest
Hello, Tuesday I am heading off to the biggest pencil in the world for the Winter SWL Fest in Kulpsville. I am going to do some informal demos of the USRP and GNURadio. They have a digital radio table in an exhibit room where they demo DRM. This year they want to do some demos of HD Radio and Internet Radio. I am thinking of showing RDS (RDBS) and SCA decoders. Hopefully next year I can actually do a talk on SDR. Although this gathering is somewhat informal, they had some good talks on DRM , SDR, and the dreaded BPL. The focus is on Shortwave but there are also some VHF/UHF and Free-To-Air Satellite talks and demos. This is the 20th fest so they are doing something right. http://www.swlfest.com/ I am also going to bring my Radio Shack HD radio which is also a SDR. The AM/FM signal is converted to 10.7 MHz and goes to a DDC. The DDC converts it to baseband for a TI DSP chip that does both analog and IBOC decoding. Thanks to USRP and GNURadio I understand how it is done. The Sangean HDT-1 also uses a similar module. 73 Eric ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
[Discuss-gnuradio] USRP 4 Questions
Hello, I managed to blow the smd fuse on my USRP. It seems to be a 1 Amp 603 fuse. Is there a certain one I need to buy? I would like to order one from Mouser. I got the enclosure recently. Where do I plug the fan in? Should the fan exhaust the air from the enclosure? 73 Eric. ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
Re: [Discuss-gnuradio] Playstation 3
Frank Brickle wrote: Robert McGwier wrote: They are $599 at my local Target. So much for bargains at Costco. Eric A. Cottrell wrote: I was at my local Costco tonight and noticed they have the 60GB PS3 for $699. I almost bought one but decided to check a Costco in NH first. $699 gets you one from Terrasoft with Yellow Dog Linux installed. Mine shipped this afternoon. Frank Hello, Looks like Terrasoft was very conservative when they mentioned a time frame of March or April. The Costco one is a bundle with an extra wireless controller. Likely a good deal if you use it for games. I will check out Target and Walmart. I looked at the Walmart website and it appeared you could only buy packages that drove the price up to $900 or more. Is the 20 GB version missing something important for linux/GNURadio use? Is it possible to put a bigger hard drive in? 20 and 60 GB hard drives are so last century. :) 73 Eric ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
Re: [Discuss-gnuradio] Playstation 3
Hello, What are PS3 owners on the list using for video displays? Do I need a HDMI monitor with HDCP? The info I have says no video out the HDMI port at all if the monitor does not have HDCP. 73 Eric ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
[Discuss-gnuradio] Cheap Front End for USRP
Hello, I heard about this on the DRM list and bought one today. A lot of Icom PCR-100 receivers are on eBay with a Buy Now of $75 each. Ships to US addresses only. http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItemsspagename=STRK%3AMEWA%3AVRIviewitem=item=140080487323rd=1rd=1 Receiver does not have SSB but is computer controlled and can be modified for IF out like the PCR1000. http://wiki.radioreference.com/index.php/PCR-100 I remember comments about HF front ends for the USRP being as expensive as full radios. Here is a cheap receiver that can be modified to be a cheap USRP front end. I am not connected in any way with the seller or auction other than being a buyer of one of the units. 73 Eric ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
[Discuss-gnuradio] Vectorscope and Constellation sink?
Hello, I want to do some work with QAM and C-QUAM. Is there a method to view phase information using the I/Q signals? I can not seem to find a vectorscope and constellation sink. 73 Eric ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
Re: [Discuss-gnuradio] On-site Training Now Available for GNU Radio and USRP
Johnathan Corgan wrote: Corgan Enterprises now offers a two-day, on-site training course for beginning and intermediate GNU Radio software and USRP users. Hello, Sounds interesting. Is there any off-site training for GNU Radio and USRP? Maybe in connection with DCC or other event? Somehow I think on-site training for one person will be rather expensive. 8) 73 Eric ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
Re: [Discuss-gnuradio] On-site Training Now Available for GNU Radio and USRP
Johnathan Corgan wrote: I'm not aware of anything formal that exists now. Eric, Matt, and I are looking into it and trying to judge demand for a deep immersion class that goes beyond just GNU Radio/USRP and more fully covers SDR, DSP, and RF design in general, using GR/USRP as teaching aids. Hello, I am interested. I have just enough knowledge of SDR, DSP, and RF to be interested in using it but not enough to really do anything useful. Within two months is the 20 year mark of my employment at my current employer and I was thinking of asking for a sabbatical for professional development. Classes would be great. 73 Eric ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
Re: [Discuss-gnuradio] PlayStation 3
Bob McGwier wrote: I understand the need and/or desire to do this natively but we really want to be doing cross platform for this target. 256 MB is not enough for these large compiles. DO NOT get on Terra's Yellow Dog pre-installed PS3 list if you have not already done so. They have taken the $100 with no guarantee and they will not even hazard a guess as to a delivery date. I did not save a single dime since I could have download FC5 and IBM Cell SDK2.0 for free and done the install myself and purchased the thing from Fry's or elsewhere. IBM has a step by step procedure for doing the Linux install on their web site. Myriad videos doing disk drive upgrades, etc. are on YouTube.I am not pleased with Terra AT ALL. People are able to get one and leave the store from Fry's and do the install themselves. I do not want to wait until March so I am going to use an extra lever I have that most people do not have (think of it as the fake wheel chair person going to the head of the line at Disney World and you will understand) but this is good for one only. Bob Hello Bob, Thanks for the information. I had questions on how to install linux on the thing. Alot easier than the XBox. http://www-128.ibm.com/developerworks/power/library/pa-linuxps3-1/ The web page indicates the video options may be limited. No VGA and the HDMI requires monitors with HCP. Likely Terra is low on the allocation list since they are not a major game retailer. 73 Eric ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
[Discuss-gnuradio] PlayStation 3
Hello, So has anyone got their PS3 yet? A store claims to have the 60 gb model a not too far distance away and I am tempted. But I do not want to be first on the block to get one. 73 Eric ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
[Discuss-gnuradio] USRP WFM SCA RX Example
Hello, Here is a bit of code that will receive SCA analog subcarriers of FM Broadcast Stations using the USRP. It is a modified version of usrp_wfm_rcv.py. Common SCA frequencies are 67 kHz and 92 kHz. SCA is used for Reading Services for the Blind, Background Music, Foreign Language Services, and other services. Remember you may hear static when tuned to a FM station because this code only outputs SCA audio. The USRP gain is critical for good decoding. Adjust for minimum noise. I use the Post FM Demod FFT to check for SCA subcarriers and to adjust the USRP gain for the lowest noise floor. The stereo pilot at 19 KHz, the stereo difference signal around 38 KHz, and RDS at 57 KHz are also displayed on the Post FM Demod FFT if present. The range below 67 kHz is used for SCA only when Stereo is not used. The SCA recieve range is not as far as the main FM carrier receive range so tune in strong local stations first. I tried to comment the code with the various parameters. There seems to be several choices for a couple of them. I coded the common ones I see here. In the local area there are a couple of stations using digital SCA. These look similar to narrow DRM signals and I wonder if they are using OFDM. Have fun, I am! 73 Eric #!/usr/bin/env python from gnuradio import gr, gru, eng_notation, optfir from gnuradio import audio from gnuradio import usrp from gnuradio import blks from gnuradio.blksimpl.fm_emph import fm_deemph from gnuradio.eng_option import eng_option from gnuradio.wxgui import slider, powermate from gnuradio.wxgui import stdgui, fftsink, form from optparse import OptionParser import usrp_dbid import sys import math import wx def pick_subdevice(u): The user didn't specify a subdevice on the command line. Try for one of these, in order: TV_RX, BASIC_RX, whatever is on side A. @return a subdev_spec return usrp.pick_subdev(u, (usrp_dbid.TV_RX, usrp_dbid.TV_RX_REV_2, usrp_dbid.BASIC_RX)) class wfm_rx_sca_graph (stdgui.gui_flow_graph): def __init__(self,frame,panel,vbox,argv): stdgui.gui_flow_graph.__init__ (self,frame,panel,vbox,argv) parser=OptionParser(option_class=eng_option) parser.add_option(-R, --rx-subdev-spec, type=subdev, default=None, help=select USRP Rx side A or B (default=A)) parser.add_option(-f, --freq, type=eng_float, default=100.1e6, help=set frequency to FREQ, metavar=FREQ) parser.add_option(-g, --gain, type=eng_float, default=40, help=set gain in dB (default is midpoint)) parser.add_option(-V, --volume, type=eng_float, default=None, help=set volume (default is midpoint)) parser.add_option(-O, --audio-output, type=string, default=, help=pcm device name. E.g., hw:0,0 or surround51 or /dev/dsp) (options, args) = parser.parse_args() if len(args) != 0: parser.print_help() sys.exit(1) self.frame = frame self.panel = panel self.vol = 0 self.state = FREQ self.freq = 0 # build graph self.u = usrp.source_c()# usrp is data source adc_rate = self.u.adc_rate()# 64 MS/s usrp_decim = 200 self.u.set_decim_rate(usrp_decim) usrp_rate = adc_rate / usrp_decim # 320 kS/s chanfilt_decim = 1 demod_rate = usrp_rate / chanfilt_decim sca_chanfilt_decim = 5 sca_demod_rate = demod_rate / sca_chanfilt_decim #64 kHz audio_decimation = 2 audio_rate = sca_demod_rate / audio_decimation # 32 kHz if options.rx_subdev_spec is None: options.rx_subdev_spec = pick_subdevice(self.u) self.u.set_mux(usrp.determine_rx_mux_value(self.u, options.rx_subdev_spec)) self.subdev = usrp.selected_subdev(self.u, options.rx_subdev_spec) print Using RX d'board %s % (self.subdev.side_and_name(),) #Create filter to get main FM Channel we want chan_filt_coeffs = optfir.low_pass (1, # gain usrp_rate, # sampling rate 100e3,# passband cutoff 140e3, # stopband cutoff 0.1, # passband ripple 60) # stopband attenuation #print len(chan_filt_coeffs) chan_filt = gr.fir_filter_ccf (chanfilt_decim, chan_filt_coeffs) #Create demodulator block for Main FM Channel max_dev = 75e3 fm_demod_gain = demod_rate/(2*math.pi*max_dev) self.fm_demod = gr.quadrature_demod_cf (fm_demod_gain) # Note - deemphasis is not applied to the Main FM Channel as main audio is not
Re: [Discuss-gnuradio] AOR 5000 as front end to USRP
Eric Blossom wrote: On Sun, Dec 31, 2006 at 01:42:31PM -0500, Eric A. Cottrell wrote: Hello, Thanks to both of you for the information. I got the RX PGA gain up all the way. I rewound the isolation transformer to be 1:1 with 14 turns. I still have to turn off AGC for good signal levels but I got 20 to 30 dB SNR on RCI at noon today. Doing some simple tests with the PSD display in DReam I can not see the noise floor increase when the receiver connected. The FFT from the USRP data also shows no increase so an amplifier is needed. What amplifier do you use on the AR8600? I used a Ramsey PR2 broadband preamp (it's probably overkill, but it's what I had on hand) http://www.ramseyelectronics.com/cgi-bin/commerce.exe?preadd=actionkey=PR2 Eric Hello, Yeah, it looks like exactly what I need. Maybe I will also try hooking an antenna up to it and fry my LFRX board from the local AM radio station down the street. :) There is a local store that sells Ramsey Kits so I may look there Tuesday night. I seem to remember AMSAT-NA was giving out MMICs one year at the symposium. I should see if I have any. The problem is finding them as my for a rainy day cache is huge. Is the PR2 battery powered or does it have a DC In? I hope it is 12 volts. 73 Eric ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
Re: [Discuss-gnuradio] Re: DReaM and gnuradio
Matteo Campanella wrote: Search the list on the subject - I did a posting some time ago about using DRM decoder with USRP bymeans of tmpfs ram based named pipe for interface... Hello, I looked it up and tried it with the analog demodulator. The local AM station came out with half speed audio! I suspect the problem is I am outputing two shorts to represent a complex waveform. It appears DReaM's -C parameter does not work with files and it expects just audio samples. Maybe I will fix it. So I am still using my USB audio approach but your approach seems better in the long run. Not being a real Unix geek and serving time in Windows Prison means I do not think of neat things like fifos. I did some rough measurements and using the USRP with the AOR 5000 IF Out gains me 8 to 10 db SNR over the No-Mod method. It appears I have to get a 10 db or so amplifier for the IF Output. I have to run with AGC Off to get a somewhat decent output. I really like GNUradio and the USRP so far. I needed a 10.7 MHz to 12 KHz converter and I built one in software with some help. 73 Eric 73 Eric ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
[Discuss-gnuradio] AOR 5000 as front end to USRP
Hello, Does anyone use a AOR 5000 as a front end for the USRP? The docs for the USRP say that it is not very sensitive but I thought the IF Output from a AOR 5000 could drive it. It seems to work for strong signals but I am getting the impression that a 10 dB or so amplifier would improve the situation. Is there a difference between the Basic Rx and the LFRX board? I have the LFRX board. Is it better to drive the LFRX single ended into one input or differential with the A and B inputs? 73 Eric ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
Re: [Discuss-gnuradio] DReaM and gnuradio
Charles Swiger wrote: Hi Gang - Did somebody have the DRM decoder working with a gnuradio receiver? The main issue is feeding the sound from gnuradio into DReaM, somehow, other than using two soundcards. I have DReaM 1.6.25 compiled. http://sourceforge.net/projects/drm/ TIA --Chuck Hello, I am setting up the DReaM decoder using the USRP. I am gradually getting it to work and managed to copy Radio New Zealand this morning on 9690. I was using the No-Mod DRM Mod for the AOR 5000 but found I needed a very good signal to get anything. I am using the 10.7 MHz IF out of my AOR 5000 reciever connected to the USRP with Basic RX via a torroid transformer. The transformer was originally used to cut down noise but I had to make it a step-up transformer to increase the signal level. The secondary is connected to RX A and RX B as a differential input. I used similar code to what was posted on the list in 2005 to convert the 10.7 MHz to baseband. I resample the baseband from 64000 samples per second to 48000 samples per second and output it to a Griffin iMic USB Audio dongle. I am outputing stereo (I/Q). I am going to try using Jack to loopback the audio but currently I am looping the iMic output to the iMic input. DReaM is setup to use I/Q by using the -c 4 parameter. I use -c 4 because the IF Output spectrum is inverted. DReaM outputs to my main speakers on the laptop. The laptop I use does not have line in so I use the iMic for other decoding and get two outputs in the process. The iMic is not very expensive but using jack is even cheaper. 73 Eric ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
Re: [Discuss-gnuradio] PlayStation 3
Robert McGwier wrote: Now if we can only get our hands on one or more of these PS3's. If you want to get a real laugh, search for PS3 using froogle and look at all of the listings in the thousands of dollars. MADNESS. Anyway, now that we have very good information, I have placed my pre-order with Yellow Dog Linux FROM Yellow Dog Linux for $100. This is a nonrefundable deposit. If you do this, it comes preloaded with YDL, running when it shows up, and the delta price between PS3 and PS3+YDL is less than them individually. Bob Hello, Not to mention the violence associated with just owning or wanting to own the PS3. March/April time frame seems like a long time to wait for a device released in November. Might as well buy one at Dayton. Pre-Christmas shopping for hot items is insane madness. There may be some hope in January to get one. My company has given me Boxing Day off as a bonus. I am going to hang around and see if I can pick up a PS3 after the user has fallen into The Uncanny Valley. :) What is the street price for a PS3? I read somewhere that there is $800 worth of hardware in the box. Does that make it a $1200 to $1600 toy? Isn't USB getting too slow for input with this type of box? How am I going to decode and display two HDTV signals at the same time? 73 Eric ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
[Discuss-gnuradio] Interfacing GNURadio with other software
Hello, I want to interface GNURadio to a software decoder. The output could be regular audio, discriminator audio, or 12 KHz IF. I could hook up my iMIC and jumper the line output to the line input but this is not a neat way to do it. Is there a loopback audio device, maybe using Jack? Maybe Jack can do this directly? It also seems possible to create a sound driver in ALSA that looks like a sound card with the output looped back to the input. I tell GNURadio to output to DSP1 and the other program to input from DSP1. 73 Eric ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
Re: [Discuss-gnuradio] RDS fun and hello from a new user
Matteo Campanella wrote: Hello Eric, I am basically doing the same you did on the RDS code and specification; right now I have introduced syndrome based sync and indeed it looks like it get synced much faster. I am using the wfm receiver (non pll), but, not having implemented the loss of sync yet, I cannot tell how fst sync comes and goes :) The ideal thing would be to build up a wxwidget from python able to show the rds data in a fancy way, in order to complete the FM receiver with RDS info on GUI - given the time left over from work I think it'll take ages, and right now priority one is to work Laccadive Islands DXpedition :) 73 matteo iz2eeq Hello, The specification gives some suggestions about loss of sync. I just count up to 20 errors in a row then resync. I want to implement error correction. I came across some example code for RDS when researching BCH codes. A RDS Explorer app would be neat. Have it display the PI, PS, RT and various codes. Right now I am dumping text out the console: PI KAKZ Pgm Top 40 Group 0A PS = Beyonce Mono PI KAKZ Pgm Top 40 Group 8A UKN 1: 9 2: 41da 3: 482c PI KAKZ Pgm Top 40 Group 0A PS = Beyonce Mono PI KAKZ Pgm Top 40 Group 2A RT: txt seg = 28, a/b = 1 RT A: Beyonce - Irreplaceable - KISS 108 - s RT B:Beyonce - Irreplaceable - KISS 108 - s PI KAKZ Pgm Top 40 Group 0A PS = Beyonce Mono PI KAKZ Pgm Top 40 Group 8A UKN 1: 9 2: 197 3: 410c PI KAKZ Pgm Top 40 Group 3A AI Group 8A Message = 40c0 AID = cd46 PI KAKZ Pgm Top 40 Group 0A PS = Iryonce Mono PI KAKZ Pgm Top 40 Group 2A RT: txt seg = 32, a/b = 1 RT A: Beyonce - Irreplaceable - KISS 108 - s RT B:Beyonce - Irreplaceable - KISS 108 - s PI KAKZ Pgm Top 40 Group 0A PS = Irrence Mono PI KAKZ Pgm Top 40 Group 8A UKN 1: 9 2: 197 3: 410c PI KAKZ Pgm Top 40 Group 0A So far I found one station has the traffic flag on all the time and the station I dumped above has the wrong PI set. Most Stations put the artist and title in a dynamic PS as above (A no-no in Europe). Several stations are broadcasting traffic information (AID = cd46). The factory radio in my car decodes RDS but after comparing the info the car radio does not display RT messages. 73 Eric ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
[Discuss-gnuradio] RDS fun and hello from a new user
Hello, Months ago I bought a USRP. Nice piece of Hardware but I did not really dive into GNURadio until this weekend. Still learning about it. I am also busy maintaining software that decodes Trunked Radio Control Channels and LTR variants like NTS Passport. I am a Boston area Ham and member of AMSAT. Seems like a number of AMSAT members are on the list. I am interested in RDS (also called RDBS here) so I downloaded the latest code from SVN. I merged the code posted on the list and got it all compiled. I was able to decode a couple of stations but the current code seemed to miss a number of strong local stations, I looked over the code and the RDBS standard. I fixed a few minor bugs like the RT strings not being stored properly. I even added decoding of the Callsign for RDBS. I have to put in a option for RDS/RBDS. I noticed the RDBS standard recommends looking for two good 26 bit words with sequential offset words. So I changed the sync to look for two good words with A B offsets. This improved things greatly and I can copy alot more RDS streams with quick sync up times. Now some stations are solid but the decoder will drift in and out of sync on others. It seems to be slipping a half bit. I also found the gain adjustment can be critical when using usrp_wfm_rcv_pll_rds.py It also seems a pilot tone is required for the decoder to work and one station here has RDS without a stereo subcarrier. I want to try using another FM detector besides the PLL one. 73 Eric ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
