Re: [Discuss-gnuradio] Questions about bbn_80211b_rx.py
You mentioned the transmitter is off. What happen if you start the corresponding tx? Another thing is, you may wanna try lower sampling rate by using bigger decim rate. Best, Guanbo On Dec 5, 2012, at 4:16 PM, Kexiong Zeng wrote: > Hi all, > > I am implementing the BBN80211 projects now. I have the following questions: > > I run my receiver (with transmitter off): ./bbn_80211b_rx.py -d 4 -f 2.437G > -b -g 100 -v > The result is: > > shine@ubuntu:~/Projects/bbn_80211/branches/usrp2_version/gr-bbn/src/examples$ > sudo ./bbn_80211b_rx.py -d 4 -f 2.437G -b -g 100 -v > adc frequency = 1 > decimation frequency = 4 > input_rate = 2500 > gain = 100.0 > desired freq = 243700.0 > baseband frequency 0.0 > dxc frequency -3700.0 > >>> gr_fir_ccf: using SSE > Recieved (short) header! > signal: 0x37 > service: 0xD9 > length: 0xB5D6 > crc: 0xAA78 > Calculated crc: 0x1DD1 > *** BAD CRC *** > Recieved header! > signal: 0xF0 > service: 0xAF > length: 0x7367 > crc: 0x9C3D > Calculated crc: 0xA7A4 > *** BAD CRC *** > Recieved header! > signal: 0xB4 > service: 0x4F > length: 0xE127 > crc: 0x42E5 > Calculated crc: 0x3BA3 > *** BAD CRC *** > Recieved (short) header! > signal: 0x0A > service: 0x88 > length: 0xBF87 > crc: 0xB627 > Calculated crc: 0x66E6 > *** BAD CRC *** > > As you can see, I always fail the CRC check and cannot decode the 80211 > packets successfully. > > I saw some people encountered the same problems as mine but no solutions were > posted. Can anyone help? > > Many thanks! > Curtis > ___ > Discuss-gnuradio mailing list > Discuss-gnuradio@gnu.org > https://lists.gnu.org/mailman/listinfo/discuss-gnuradio ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org https://lists.gnu.org/mailman/listinfo/discuss-gnuradio
Re: [Discuss-gnuradio] benchmark_rx kept showing 000000...
"O" = overrun (PC not keeping up with received data from usrp or audio card) "U" = underrun (PC not providing data quickly enough) You can try to reduce the sampling rate or use a better powerful machine. :) On Thu, Jun 7, 2012 at 2:15 PM, Weixian Zhou wrote: > I had successfully transmit data without any problems using > benchmark_tx/benchmark_rx moment ago: > *./benchmark_rx.py -f 2.42G -r 2M* > *./benchmkar_tx.py -f 2.42G -r 2M* > > But after a few tries, the rx end started to show ... The wired thing > is that I input the same parameters as before but the result is different: > *bell@bell-HP-Compaq-4000-Pro-SFF-PC:~/Desktop/USRP/gnuradio/gr-digital/end$ > ./benchmark_rx.py -f 2.47G -r 2M* > *linux; GNU C++ version 4.6.3; Boost_104601; UHD_003.004.001-129-g23344268 > * > * > * > *>>> gr_fir_ccf: using SSE* > *-- Opening a USRP2/N-Series device...* > *-- Current recv frame size: 1472 bytes* > *-- Current send frame size: 1472 bytes* > * > * > *UHD Warning:* > *Unable to set the thread priority. Performance may be negatively > affected.* > *Please see the general application notes in the manual for > instructions.* > *EnvironmentError: OSError: error in pthread_setschedparam* > * > * > *No gain specified.* > *Setting gain to 49.50 (from [0.00, 99.00])* > *Warning: Failed to enable realtime scheduling.* > *Using Volk machine: ssse3_32* > * > OO > * > > I am using the two USRP N210, the daughter boards are both XCVR2450. > Ubuntu 12.04, latest version of UHD and GNU Radio. > -- > Regards, > Weixian Zhou > > > > ___ > Discuss-gnuradio mailing list > Discuss-gnuradio@gnu.org > https://lists.gnu.org/mailman/listinfo/discuss-gnuradio > > -- Regards, Brian ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org https://lists.gnu.org/mailman/listinfo/discuss-gnuradio
Re: [Discuss-gnuradio] What interference signals exist in 5Ghz ?
I checked the US spectrum allocation chart, there are some devices like radar and satellite communication in the 5GHz bands. Based on the comment of Cisco, "It is generally true that fewer devices currently operating at 5 GHz are causing interference as compared to 2.4-GHz devices. But this will change over time. Just as everyone moved from 900 MHz to 2.4 GHz to avoid interference, the "band jumping" effect will catch up with 5 GHz. Some devices that already exist at 5 GHz include cordless phones, radar, perimeter sensors, and digital satellite." http://www.cisco.com/en/US/prod/collateral/wireless/ps9391/ps9393/ps9394/prod_white_paper0900aecd807395a9_ns736_Networking_Solutions_White_Paper.html Guanbo On Thu, Jun 7, 2012 at 12:47 PM, Sangho Oh wrote: > It is well know that microwaves, bluetooth, cordless phones are the major > interference sources in 2.4Ghz. > But what devices (with non WiFi standards) are using 5Ghz band used by > 802.11n devices? > Specifically for 5180-5350, 5745-5805Mhz. > > > > ___ > Discuss-gnuradio mailing list > Discuss-gnuradio@gnu.org > https://lists.gnu.org/mailman/listinfo/discuss-gnuradio > > -- Regards, Brian ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org https://lists.gnu.org/mailman/listinfo/discuss-gnuradio
Re: [Discuss-gnuradio] Remote Access to USRP testbed with GNU Radio
Thanks a lot for all the replys! Sorry that I forgot to mention I am using USRP2. I think the link is for USRP which create a usrp group for non root control. Best, Guanbo On Oct 7, 2011, at 6:01 AM, Robert McGwier wrote: > I believe people are answering the question but are slightly off target. > > Create a group on your Linux distribution call USRP, make sure those users > you want control the USRP as users (AND NOT ROOT) are in this group. The go > read the gnuradio wiki about the other changes granting device permissions > etc. This is how remote users gain control of the USRP locally without sudo > as well as over SSH whether the machine is accessible over a LAN only or the > full internet. > > Bob > On Oct 6, 2011 7:15 PM, "Ian Buckley" wrote: > Remember that you in fact are not required to "Login" to the USRP at all, it > isn't an interactive device, more like a peripheral device to a host > computer. Thus your remote access limitation is purely dependent on the > remote host you utilize to run GNURadio to interface to the USRP. The main > issue you are like to run into is using update intensive GRC graphical tools > such as FFT via X or VNC which can be very problematic over WANs. In terms of > the USRP itself, if the location is truly remote with no local support then > it would be wise to utilize A USRP other than the USRP2 since this model > requires the SDCard to be physically replaced to upgrade firmware+FPGA. It > would also be wise to have a remote accessible PDU so you can power cycle the > USRP if necessary. > > I've built austere "lights out" remote satellite ground stations that use > USRP's with great success. > > -Ian > > On Oct 6, 2011, at 3:31 PM, Kunal Kandekar wrote: > >> I have accessed and used a USRP over SSH before. In fact, I accessed it over >> the Internet, not just a LAN. Although I was not the one who set it up, as >> far as I know, nothing additional had to be done to enable this. I simply >> logged in as the user account under which GNU Radio had been installed. The >> machine was running Ubuntu, in case it matters. >> >> Kunal >> >> >> On Thu, Oct 6, 2011 at 6:04 PM, Guanbo Zheng wrote: >> Hi, all >> >> We are interesting to build up a USRP testbed which allowed the guest remote >> access to do some experiments. >> I have seen someone's youtube video that they control the USRPs to transmit >> different signals through SSH access. >> But I want to double check if it allowed guest control of USRP devices ? >> >> Are there any other settings I need to take care of, in order to implement >> this? >> >> Thanks a lot for any suggestions! >> >> -- >> Regards, >> Guanbo >> >> ___ >> Discuss-gnuradio mailing list >> Discuss-gnuradio@gnu.org >> https://lists.gnu.org/mailman/listinfo/discuss-gnuradio >> >> >> ___ >> Discuss-gnuradio mailing list >> Discuss-gnuradio@gnu.org >> https://lists.gnu.org/mailman/listinfo/discuss-gnuradio > > > ___ > Discuss-gnuradio mailing list > Discuss-gnuradio@gnu.org > https://lists.gnu.org/mailman/listinfo/discuss-gnuradio > > ___ > Discuss-gnuradio mailing list > Discuss-gnuradio@gnu.org > https://lists.gnu.org/mailman/listinfo/discuss-gnuradio ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org https://lists.gnu.org/mailman/listinfo/discuss-gnuradio
[Discuss-gnuradio] Remote Access to USRP testbed with GNU Radio
Hi, all We are interesting to build up a USRP testbed which allowed the guest remote access to do some experiments. I have seen someone's youtube video that they control the USRPs to transmit different signals through SSH access. But I want to double check if it allowed guest control of USRP devices ? Are there any other settings I need to take care of, in order to implement this? Thanks a lot for any suggestions! -- Regards, Guanbo ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org https://lists.gnu.org/mailman/listinfo/discuss-gnuradio
Re: [Discuss-gnuradio] OFDM benchmark transmit signal bandwidth
Great!! Thanks for your explanation! Guanbo On Fri, Sep 9, 2011 at 5:41 PM, Tom Rondeau wrote: > On Fri, Sep 9, 2011 at 6:36 PM, Guanbo Zheng wrote: > >> >> >> On Fri, Sep 9, 2011 at 8:18 AM, Tom Rondeau wrote: >> >>> On Thu, Sep 8, 2011 at 6:47 PM, Guanbo Zheng wrote: >>> >>>> Hi all >>>> >>>> I am currently using OFDM benchmark to generate OFDM signal under the >>>> setting of FFT len, CP length, occupied-tones and something. >>>> But I can not find out what is the real bandwidth of signal it >>>> generated. >>>> Because when I changed the Interpolation rate (sampling rate), the >>>> bandwidth at RX changed as well. >>>> Ideally we know that setting enough large sampling rate ( In USRP2, the >>>> max fs = 25MHz), I should observe the constant signal with fixed BW. >>>> It seems to me that BW of the generated signal is too large. >>>> >>>> My question is: how to determine the BW of transmit signal in the codes? >>>> where I can change it. >>>> All I found is actual bit rate = (converter_) / xrate / >>>> samples_per_symbol = 100MHz/4/2. But this one seems not related to the BW >>>> of >>>> signal itself. >>>> >>>> Thanks for any suggestions! >>>> -- >>>> Regards, >>>> Guanbo >>> >>> >>> >>> Guanbo, >>> The bandwidth of the signal changes with the interpolation rate. If you >>> set the interpolation rate such that you get 25 MHz of bandwidth out, then >>> the OFDM signal will also have a 25 MHz bandwidth. What you will _see_ over >>> the air is 25e6 * (occupided_tones/fft_length), since the ratio of the used >>> tones to the number of subcarriers is the amount of occupied bandwidth. >>> >>> You can also think of it this way. The bandwidth of a subcarrier is >>> BW/fft_length, where BW is the sample rate out of the USRP. >>> >>> Tom >>> >>> >> Hi Tom >> >> What you means that, the bandwidth of OFDM signal is actually equal to >> the sampling rate*occupided_tones/fft_length. >> > > I mean exactly that :) > > >> Then how to understand the sampling theory, in which sampling rate is >> twice of bandwidth? >> > > Complex signals. Sample rate is the bandwidth. Have a sample for I and Q, > so we still have enough information so as not to violate Nyquist. > > >> Thanks, >> Guanbo >> >> >> -- >> Regards, >> Guanbo >> > > Tom > > -- Regards, Guanbo ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org https://lists.gnu.org/mailman/listinfo/discuss-gnuradio
Re: [Discuss-gnuradio] OFDM benchmark transmit signal bandwidth
On Fri, Sep 9, 2011 at 8:18 AM, Tom Rondeau wrote: > On Thu, Sep 8, 2011 at 6:47 PM, Guanbo Zheng wrote: > >> Hi all >> >> I am currently using OFDM benchmark to generate OFDM signal under the >> setting of FFT len, CP length, occupied-tones and something. >> But I can not find out what is the real bandwidth of signal it generated. >> Because when I changed the Interpolation rate (sampling rate), the >> bandwidth at RX changed as well. >> Ideally we know that setting enough large sampling rate ( In USRP2, the >> max fs = 25MHz), I should observe the constant signal with fixed BW. >> It seems to me that BW of the generated signal is too large. >> >> My question is: how to determine the BW of transmit signal in the codes? >> where I can change it. >> All I found is actual bit rate = (converter_) / xrate / >> samples_per_symbol = 100MHz/4/2. But this one seems not related to the BW of >> signal itself. >> >> Thanks for any suggestions! >> -- >> Regards, >> Guanbo > > > > Guanbo, > The bandwidth of the signal changes with the interpolation rate. If you set > the interpolation rate such that you get 25 MHz of bandwidth out, then the > OFDM signal will also have a 25 MHz bandwidth. What you will _see_ over the > air is 25e6 * (occupided_tones/fft_length), since the ratio of the used > tones to the number of subcarriers is the amount of occupied bandwidth. > > You can also think of it this way. The bandwidth of a subcarrier is > BW/fft_length, where BW is the sample rate out of the USRP. > > Tom > > Hi Tom What you means that, the bandwidth of OFDM signal is actually equal to the sampling rate*occupided_tones/fft_length. Then how to understand the sampling theory, in which sampling rate is twice of bandwidth? Thanks, Guanbo -- Regards, Guanbo ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org https://lists.gnu.org/mailman/listinfo/discuss-gnuradio
[Discuss-gnuradio] OFDM benchmark transmit signal bandwidth
Hi all I am currently using OFDM benchmark to generate OFDM signal under the setting of FFT len, CP length, occupied-tones and something. But I can not find out what is the real bandwidth of signal it generated. Because when I changed the Interpolation rate (sampling rate), the bandwidth at RX changed as well. Ideally we know that setting enough large sampling rate ( In USRP2, the max fs = 25MHz), I should observe the constant signal with fixed BW. It seems to me that BW of the generated signal is too large. My question is: how to determine the BW of transmit signal in the codes? where I can change it. All I found is actual bit rate = (converter_) / xrate / samples_per_symbol = 100MHz/4/2. But this one seems not related to the BW of signal itself. Thanks for any suggestions! -- Regards, Guanbo ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org https://lists.gnu.org/mailman/listinfo/discuss-gnuradio
Re: [Discuss-gnuradio] how to decide the msgq_limit?
I have a vey similar issue in sending packets using FTW ofdm, in which I tried sending only one packet but observe much more packets in file sink. I have not figured out if it is because of msgq() or something else in lower layer Best, Guanbo On Mar 3, 2011, at 7:03 PM, Yan Nie wrote: > Dear all, > > I'm using gr.message_source as the signal source and using multiply_const_ff > to set the amplitude of the signal then feeding the signal into USRP1 with > LFTX plugged-in. The message need to be transmitted in my project is 3315 > bytes. After the flow graph starting to run, msgq.insert_tail() is utilized > to insert the message into the flow graph. The amplitude changes every time > after the message is transmitted. I only called insert_tail() once in every > cycle of transmission to feed the message and expect the message to be sent > once, but the result turns out the times of the message transmission is > ranging from once to 10 times, which means sometimes the message is only > transmitted once, sometimes it continuously repeated 10 times. What's the > problem would be? What decide the parameter, msgq_limit, which is the maximum > number of message in the message queue? Can I send this 3315 bytes data as > one message and set the msgq_limit as 1? > > Really appreciate any of your suggestion! > > Thanks, > Yan > > The code related to message insert > try: > while 1: >tb.set_amplitude(2000) >msg_13bit = gr.message_from_string(payload_13bit) >tb._ls.msgq.insert_tail(msg_13bit) >tb.set_amplitude(0) >msg_stop = gr.message_from_string(payload_stop) >tb._ls.msgq.insert_tail(msg_stop) > > ___ > Discuss-gnuradio mailing list > Discuss-gnuradio@gnu.org > http://lists.gnu.org/mailman/listinfo/discuss-gnuradio ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
Re: [Discuss-gnuradio] FTW IEEE802.11a/g/p OFDM Frame Encoder
Hi, Paul Thanks for your description. I finally figure out the problem that the Gigabyte Ethernet Card in my computer does not support Gigabyte. Either it is because of driver problem or itself. After using another good Ethernet card, it works smoothly. :) I have another question for FTW OFDM, in which I wanna implement the transmit-wait-transmit scenario. Specifically, I tried to transmit some data stream first, sleep for a few second and then transmit another one. $ sudo python ftw_ofdm_tx.py -e eth1 -f 2.462G -i 5 --regime=3 -g 30 -r 1 However, from the spectrum I have observe, it seems USRP2 keeps generating the same signal, without any sleeping or waiting time. By looking into the codes, I found msgq() seems to be fine. Also, when there is no payload, EOF set to true, telling the msgq() no more messenge. Then, what is the possible reason for my problem? Any suggestions are appreciated! Thanks, Guanbo On Tue, Feb 22, 2011 at 7:40 AM, Paul Fuxjäger wrote: > Guanbo ZHENG wrote on 22.02.11 00:36: > > > The frequency band is correct. Just now, I re-install the repository from > > the CGRAN, and tried again using: > > sudo python ftw_ofdm_tx.py -f 2.462G -i 5 --regime=8 --payload="Here are > > some test messages from WiSeR" -r 1 > > So the only question is, I have NOT updated my firmware. I will try that > as > > well. > > We used the XCVR2450 only so far. In our experience, the most common > reasons > why it fails are: > > 1) channel on the RX side is not set to the one you use at TX > 2) TX gain is too high or too low (depending on what kind of antennas and > "channel environment" you are using) > 3) old USRP2 firmware bug (try also with -s option and see if it changes > the > behavior) see documentation https://www.cgran.org/wiki/ftw80211ofdmtx > 4) try also with -r 1 and -r 0 (the repetition method we used in the code > is > very dirty) > > > By the way, what does the USRP2 generated packet look like in Wireshark > at > > another laptop? > > Ideally, you would tick the "capture using promiscuous mode" and "capture > using monitor mode" in the Wireshark GUI. Then you should see *every > PHY-valid frame whatsoever* the card is able to decode on the channel that > it is currently listening on. Make sure it does work like that. E.g. do you > see beacons of the access-points nearby? > > The link-layer header-type should be "802.11 plus radiotap header" and you > should see the radiotap headers appended to every frame. > > If you have it available you can also use cmd-line tool called athstats to > debug. You can get access to some atheros-specific counters with it, like > how many frame-detected events per seconds are registered by the NIC. > > > > If all of this doesnt help there is this method to find out if the problem > is in HW/GNUradio subsystem or on the encoder/decoder side: > > Try to generate frames using the Atheros NIC and record the signal (a block > of baseband to disk) using the USRP2 with rx_cfile.py. Then put the Atheros > in monitor mode again and transmit this very baseband block using > transmit.py we included in the ftwofdm release (in src/matlab). > > You have to use the same USRP2 for recording/transmission, and you should > not wait too long between RX/TX because of potential frequency offsets. > > If this "record-playback" does not work there is still something wrong in > your current XCVR2450/USRP2/GNUradio subsystem. If it does work our encoder > is the source of the problem :( > > > cheers > paul > > > > > -- > Dipl.-Ing. Paul Fuxjaeger > FTW - Telecommunications Research Center Vienna > http://www.ftw.at callto://:paul.fuxjaeger.at.work > PSTN:+43-1-505283057 | 3GPP:+43-676-4787088 > > -- Regards, Brian ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
Re: [Discuss-gnuradio] how to stop the top_block and restart signal transmission
Hi Yan
I did it as well, but it seem wait for infinite time before it is
finished.
But without the lock() and unlock(), everything returns to normal.
Thanks,
Guanbo
On Wed, Feb 23, 2011 at 5:55 PM, Yan Nie wrote:
> Hi Guanbo,
>
> In my case, I added a tb.wait() after the tb is unlock to wait for the
> unlock action finished, so that the last line shows. However, it still gives
> the carrier wave on the oscilloscope. I also tried
> top_block._u._subdev.set_enable(False) to completely disable the transmitter
> then set_enable(True) to re-enable the transmitter based on hardware
> consideration, but it still doesn't work
>
> On 02/23/11, *Guanbo * wrote:
>
>
> Hi, Yan
>
> I tried the similar python code as yours, as follows:
>
> tb.start()
> send_pkt("payload", eof=False)
> print "before lock()"
> tb.lock()
> print "after lock()"
> time.sleep(1)
> print "before unlock()"
> tb.unlock()
> print "after unlock()"
>
> I found out that, the last print is not showing up.
>
> Do you have idea regarding to this issue?
> Thanks
>
>
>
>
>
>
> Yan Nie wrote:
> >
> >
> > Hi Jason,
> >
> > I really appreciate your help about the problem that I got. The info
> > related to the GNURadio and the USRP that I'm using is listed in the
> > following.
> >>
> >> Please confirm that you just see the carrier, not your modulated
> >> signal when using the lock()/unlock()
> >
> > I checked the result of using lock()/unlock() by correlating the down
> > converted signal with the Barker code, at the transmission pause
> interval,
> > there is no correlation peak. Therefore, it turned out there is no code
> > transmitted during the transmission pause interval. Is it a right way to
> > test if there is Barker code transmitted during the transmission pause
> > interval? Is lock/unlock working for completely turning off the signal
> > transmission for 5ms? However, I'm sure when using lock/unlock method
> > still gives at least carrier signal in the pausing interval, which is
> > observed on the oscilloscope.
> >
> >>
> >> Also, please tell us:
> >>
> >> What version of GNUradio are you using?
> >
> > The version of GNUradio that I'm using is GNURadio 3.2svn
> >
> >>
> >> What hardware are you using? USRP? which daughterboard?
> >
> > I'm using USRP1 with LFTX daughterboard plug-in. (similarly, at the
> > receiver side,USRP1 with LFRX plug-in is utilized. )
> >
> >>
> >> Are you using UHD?
> >
> > I'm not using UHD.
> >
> > Thank you so much for all of your help!
> >
> > Thanks,
> > Yan
> >
> > begin:vcard
> > n:;
> > adr:;;
> > version:2.1
> > end:vcard
> >
> > ___
> > Discuss-gnuradio mailing list
> > Discuss-gnuradio@gnu.org
> > http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
> >
> >
>
> --
> View this message in context:
> http://old.nabble.com/how-to-stop-the-top_block-and-restart-signal-transmission-tp30982478p30999857.html
> Sent from the GnuRadio mailing list archive at Nabble.com.
>
>
> ___
> Discuss-gnuradio mailing list
> Discuss-gnuradio@gnu.org
> http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
>
>
--
Regards,
Guanbo
___
Discuss-gnuradio mailing list
Discuss-gnuradio@gnu.org
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Re: [Discuss-gnuradio] FTW IEEE802.11a/g/p OFDM Frame Encoder
The frequency band is correct. Just now, I re-install the repository from the CGRAN, and tried again using: sudo python ftw_ofdm_tx.py -f 2.462G -i 5 --regime=8 --payload="Here are some test messages from WiSeR" -r 1 So the only question is, I have NOT updated my firmware. I will try that as well. By the way, what does the USRP2 generated packet look like in Wireshark at another laptop? Thanks, Guanbo On Sun, Feb 20, 2011 at 11:32 PM, Ashutosh Grewal wrote: > Hi Guanbo, > > Thanks for your reply. > > I've some good news regarding the FTW OFDM encoder - we were able to > decode 802.11 a/g packets using kismet/wireshark later in the day. It seems > that we'll have to set the OFDM coderegime option as 6 or 7 or 8 (I'm not > sure about 8 but 6 definitely worked). The version information of our test > system is same as that as what is used here - > https://www.cgran.org/wiki/ftw80211ofdmtx but our USRP2 HW revision number > is different and we used the latest firmware. > > Regarding BBN USRP2Version - I'll try that and get back to you in case I > face any difficulties. > > Thanks, > > Ashu > > On 21 February 2011 00:07, Guanbo ZHENG wrote: > >> Regarding to BBN, you may try to the high interpolation and decimation >> rate, as well as proper gain. I was able to decode it on RX (Ubuntu >> 9.10+gnuradio 3.2.2) >> >> For FTW OFDM code, I was able to decode the 802.11g packet as well at >> Wireshark using an Atheros 802.11a/b/g NIC in monitor mode, where I have >> saved the TCPdump file. But recently I tried to re-conduct the experiment, I >> can not get it anymore. :( >> I am still trying to figure out what problem there is. >> >> Guanbo >> >> On Sun, Feb 20, 2011 at 3:13 PM, Sankalp Nimbhorkar < >> sankalp.nimbhor...@gmail.com> wrote: >> >>> Dear All, >>>We tried using this encoder to transmit frames with USRP2 XCVR >>> 2450 daughter-card on Ubuntu 9.10. We confirmed transmission with a WiSpy >>> dongle. But we cannot receive the frames on a receiver. The receiver we are >>> using is an Atheros 802.11 a/b/g NIC in monitor mode with Mad WiFi driver. >>> We have tried almost all the channels in 802.11a and 802.11g, but could not >>> receive a single packet on receiver. In the project description we came to >>> know that 802.11a frames were successfully received with a Ralinc NIC. Has >>> anyone tried out this project? If so, please tell us the procedure to >>> receive these frames with an NIC? Or at least some way to confirm that the >>> frame was actually received by the NIC? (We even tried Kismet configured to >>> report frames even if CRC check fails). Any help would be appreciated. >>> >>> Thank you. >>> Sankalp Nimbhorkar >>> CSC Graduate Student >>> North Carolina State University >>> >>> ___ >>> Discuss-gnuradio mailing list >>> Discuss-gnuradio@gnu.org >>> http://lists.gnu.org/mailman/listinfo/discuss-gnuradio >>> >>> >> >> >> -- >> Regards, >> Brian >> >> ___ >> Discuss-gnuradio mailing list >> Discuss-gnuradio@gnu.org >> http://lists.gnu.org/mailman/listinfo/discuss-gnuradio >> >> > -- Regards, Brian ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
Re: [Discuss-gnuradio] FTW IEEE802.11a/g/p OFDM Frame Encoder
Regarding to BBN, you may try to the high interpolation and decimation rate, as well as proper gain. I was able to decode it on RX (Ubuntu 9.10+gnuradio 3.2.2) For FTW OFDM code, I was able to decode the 802.11g packet as well at Wireshark using an Atheros 802.11a/b/g NIC in monitor mode, where I have saved the TCPdump file. But recently I tried to re-conduct the experiment, I can not get it anymore. :( I am still trying to figure out what problem there is. Guanbo On Sun, Feb 20, 2011 at 3:13 PM, Sankalp Nimbhorkar < sankalp.nimbhor...@gmail.com> wrote: > Dear All, >We tried using this encoder to transmit frames with USRP2 XCVR > 2450 daughter-card on Ubuntu 9.10. We confirmed transmission with a WiSpy > dongle. But we cannot receive the frames on a receiver. The receiver we are > using is an Atheros 802.11 a/b/g NIC in monitor mode with Mad WiFi driver. > We have tried almost all the channels in 802.11a and 802.11g, but could not > receive a single packet on receiver. In the project description we came to > know that 802.11a frames were successfully received with a Ralinc NIC. Has > anyone tried out this project? If so, please tell us the procedure to > receive these frames with an NIC? Or at least some way to confirm that the > frame was actually received by the NIC? (We even tried Kismet configured to > report frames even if CRC check fails). Any help would be appreciated. > > Thank you. > Sankalp Nimbhorkar > CSC Graduate Student > North Carolina State University > > ___ > Discuss-gnuradio mailing list > Discuss-gnuradio@gnu.org > http://lists.gnu.org/mailman/listinfo/discuss-gnuradio > > -- Regards, Brian ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
[Discuss-gnuradio] packet sending interval
Hi, I am using the OFDM benchmark code in USRP2, where my system is Ubuntu 9.10 + Gnuradio 3.2.2. Basically I used the following scripting for TX and RX: $ sudo python benchmark_ofdm_tx_new.py --mac-addr=00:50:c2:85:32:97 -f 2.462G -m qpsk -i 100 --tx-gain=30 -M 8 -s 1000 --fft-length=512 --occupied-tones=200 --cp-length=128 $ sudo python benchmark_ofdm_rx_new.py --mac-addr=00:50:c2:85:32:99 -f 2.462G -m qpsk -d 100 --rx-gain=30 --fft-length=512 --occupied-tones=200 --cp-length=128 As observed from spectrum analyzer, I found out the OFDM symbols are NOT stably transmitting. Furthermore, the packet sending interval is large ( in low rate) Then, how can I control the sending rate/interval of OFDM packets? The related code for "send_pkt" is as follows: - def send_pkt(self, payload='', eof=False): """ Send the payload. @param payload: data to send @type payload: string """ if eof: msg = gr.message(1) # tell self._pkt_input we're not sending any more packets else: info = ofdm_packet_utils.get_info(payload, self._regime, self._symbol_time) N_cbps= info["N_cbps"] N_bpsc= info["N_bpsc"] N_rate= info["rate"] N_sym = info["N_sym"] (pkt,Length) = ofdm_packet_utils.ftw_make(payload,self._regime, self._symbol_time) (pkt_scrambled,Length) = ofdm_packet_utils.scrambler(pkt,Length) pkt_coded = ofdm_packet_utils.conv_encoder(pkt_scrambled, Length, self._regime, N_cbps, N_bpsc, N_sym, N_rate) pkt_interleaved = ofdm_packet_utils.interleaver(pkt_coded , self._regime, N_cbps, N_bpsc) msg = gr.message_from_string(pkt_interleaved) self._pkt_input.msgq().insert_tail(msg) --- Thanks -- Regards, Guanbo ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
Re: [Discuss-gnuradio] daughterboard performance
It is USRP2, my system setup is Ubuntu 9.04+Gnuradio3.2.2. My test codes includes the benchmark OFDM, BBN code, which i tested smoothly before both cabling and over the air. TX uses XCVR2450, the RX uses RFX2400 or DBSRX-LF. Best, Guanbo On Feb 17, 2011, at 10:42 PM, "Marcus D. Leech" wrote: >> Hi >> >> I used XCVR2450 daughterboard for TX and RX on USRP2 and everything is >> fine. >> Recently I began to use RFX2400 and DBSRX-LF, which I found out the >> performance are much worse than XCVR2450. >> Observed from FFT plot, I found out there are some weird spectrum >> response using RFX2400 and DBSRX-LF respectively. >> Furthermore, I am not able to decode some OFDM example anymore! (I >> compensated the correct carrier frequency already) >> >> I am wondering if I need to update something like firmware, in order >> to use those two new daughterboards. >> Thanks, > You haven't given us much to go on. > > What does your test setup look like? Are you using USRP1? USRP2? > USRP-N210? Using UHD? > > Are you tests over-the-air or with cables? Are you using attenuators in > the cabling? > > > > > -- > Principal Investigator > Shirleys Bay Radio Astronomy Consortium > http://www.sbrac.org > > > > ___ > Discuss-gnuradio mailing list > Discuss-gnuradio@gnu.org > http://lists.gnu.org/mailman/listinfo/discuss-gnuradio ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
[Discuss-gnuradio] daughterboard performance
Hi I used XCVR2450 daughterboard for TX and RX on USRP2 and everything is fine. Recently I began to use RFX2400 and DBSRX-LF, which I found out the performance are much worse than XCVR2450. Observed from FFT plot, I found out there are some weird spectrum response using RFX2400 and DBSRX-LF respectively. Furthermore, I am not able to decode some OFDM example anymore! (I compensated the correct carrier frequency already) I am wondering if I need to update something like firmware, in order to use those two new daughterboards. Thanks, -- Regards, Guanbo ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
[Discuss-gnuradio] Problem of Daughterboard XCVR 2450
Hi, I am using XCVR 2450 + USRP2 (Rev 4.0). Before they works fine. However, I just found out one of them can not set frequency recently :( The problem statement is as follows: gbzh...@gbzheng-desktop:~/downloads/ofdm_example$ sudo python benchmark_ofdm_tx_new.py --mac-addr=00:50:c2:85:3a:ff -f 2.412G -m qpsk -i 100 --tx-gain=30 -M 8 -s 1000 Requested TX Bitrate: 100k Actual Bitrate: 500k Failed to set Rx frequency to 2.412G Traceback (most recent call last): File "benchmark_ofdm_tx_new.py", line 146, in main() File "benchmark_ofdm_tx_new.py", line 104, in main tb = my_top_block(options) File "benchmark_ofdm_tx_new.py", line 41, in __init__ self.txpath = usrp_transmit_path.usrp_transmit_path(options) File "/home/gbzheng/downloads/ofdm_example/usrp_transmit_path.py", line 67, in __init__ self._setup_usrp_sink(options) File "/home/gbzheng/downloads/ofdm_example/usrp_transmit_path.py", line 90, in _setup_usrp_sink raise ValueError, eng_notation.num_to_str(options.tx_freq) ValueError: 2.412G I tried different frequency band in 2.4GHz ISM bands, as well as different scale value like 241200. however, the result has no luck. Does it mean the broken daughterboard? Thanks, -- Regards, Guanbo ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
[Discuss-gnuradio] OFDM benchmark
Hello, I am trying to understand the design in benchmark OFDM code in Gnuradio. In the code, OFDM_RECEIVER use OFDM_SYNC_PN to do the timing and frequency offset synchronization, and then doing FFT_DEMOD to demodulate the signal. After that, SLICER and DEMAPPER in GR_OFDM_FRAME_SINK are used to output it in the message queue. But the questions are: Why there is PLL for carrier compensation in GR_OFDM_FRAME_SINK? Should PLL be used before FFT_DEMOD ? What is the difference between PLL here and timing and frequency synchronization in OFDM_SYNC_PN? -- Regards, Guanbo ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
[Discuss-gnuradio] costas_loop_cc ()
Hi, I found that for CFO compensation, there is the module named "costas_loop_cc ()" Use it in this way: gr.costas_loop_cc(alpha, beta, max_freq, min_freq, order) where I can find this C++ file? I search the files, only found one "gr_costas_loop_cc.cc" in ~/gnuradio-3.2.2/gnuradio-core/src/lib/general But It seems like this C++ function is not the one they use. As I tried to print out some variable, but no observations. Sorry to disturb you guys! :( -- Regards, Guanbo ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
[Discuss-gnuradio] Re: ofdm decoder problem on USRP2
I have found out the meaning of "S" and "Time out": >From here: http://www.ruby-forum.com/topic/203035 Thank you Tom! :) On Wed, Dec 1, 2010 at 8:39 PM, Guanbo Zheng wrote: > Hi, > > I am trying to build the OFDM decoder on GRC based on the FTW 802.11a/g > encoder. > > At the USRP2 receiver, after CFO compensation, I want to see the QPSK > constellation. > > Basically, the process is: > bit stream ofdm mod usrp2 sink > usrp2 source -- timing offset comp --- CFO comp ofdm demod - > constellation sink > > Before ofdm_demod, the signal spectrum observed in USRP2_fft is good as far > as I know. > But after OFDM demod block, I can not receive anything. No data output! :( > > > I read some threads by Veljko, regarding to the parameter setting of OFDM > demod block. > But I am not sure about the number of tones, SNR. > > Where can I find the definition of this block? What is the meaning of S and > Time out? > By the way, my setup environment is ubuntu 9.04 + gnuradio 3.2.2. > > -- > Regards, > Guanbo > > -- Regards, Guanbo ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
[Discuss-gnuradio] ofdm decoder problem on USRP2
Hi, I am trying to build the OFDM decoder on GRC based on the FTW 802.11a/g encoder. At the USRP2 receiver, after CFO compensation, I want to see the QPSK constellation. Basically, the process is: bit stream ofdm mod usrp2 sink usrp2 source -- timing offset comp --- CFO comp ofdm demod - constellation sink Before ofdm_demod, the signal spectrum observed in USRP2_fft is good as far as I know. But after OFDM demod block, I can not receive anything. No data output! :( I read some threads by Veljko, regarding to the parameter setting of OFDM demod block. But I am not sure about the number of tones, SNR. Where can I find the definition of this block? What is the meaning of S and Time out? By the way, my setup environment is ubuntu 9.04 + gnuradio 3.2.2. -- Regards, Guanbo ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
Re: [Discuss-gnuradio] help on BBN 802.11b code
thanks~ Tom. It is solved. Best, Guanbo On Thu, Nov 11, 2010 at 9:36 PM, Tom Rondeau wrote: > On Thu, Nov 11, 2010 at 9:59 PM, Guanbo Zheng wrote: > > Hi > > > > I tried to install the BBN 802.11b trunk from CGRAN project website, and > got > > some problems duing "sudo make", as follows: > > --- > > bbn_tap.cc: In constructor ‘bbn_tap::bbn_tap(std::string, int)’: > > bbn_tap.cc:51: error: ‘memset’ was not declared in this scope > > bbn_tap.cc:53: error: ‘strncpy’ was not declared in this scope > > bbn_tap.cc: In member function ‘int bbn_tap::tap_write(std::string)’: > > bbn_tap.cc:137: warning: format ‘%d’ expects type ‘int’, but argument 3 > has > > type ‘size_t’ > > bbn_tap.cc:153: warning: format ‘%d’ expects type ‘int’, but argument 3 > has > > type ‘size_t’ > > bbn_tap.cc:158: warning: ignoring return value of ‘ssize_t write(int, > const > > void*, size_t)’, declared with attribute warn_unused_result > > make[4]: *** [bbn_tap.lo] Error 1 > > > > The errors came from "make". The configure of the code works fine. > > > > My system is: Ubuntu 9.04 + gnuradio 3.2.2 + USRP2 + XCVR2450. > > I did the installation before, was successfully on USRP2. Not sure what > > happened this time. :( > > > > Many thanks for any advice > > > > -- > > Regards, > > Guanbo > > Likely an updated version of GCC that's being more picky about include > files. > > Try including in the offending file and recompile. > > Tom > -- Regards, Guanbo ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
[Discuss-gnuradio] help on BBN 802.11b code
Hi I tried to install the BBN 802.11b trunk from CGRAN project website, and got some problems duing "sudo make", as follows: --- bbn_tap.cc: In constructor ‘bbn_tap::bbn_tap(std::string, int)’: bbn_tap.cc:51: error: ‘memset’ was not declared in this scope bbn_tap.cc:53: error: ‘strncpy’ was not declared in this scope bbn_tap.cc: In member function ‘int bbn_tap::tap_write(std::string)’: bbn_tap.cc:137: warning: format ‘%d’ expects type ‘int’, but argument 3 has type ‘size_t’ bbn_tap.cc:153: warning: format ‘%d’ expects type ‘int’, but argument 3 has type ‘size_t’ bbn_tap.cc:158: warning: ignoring return value of ‘ssize_t write(int, const void*, size_t)’, declared with attribute warn_unused_result make[4]: *** [bbn_tap.lo] Error 1 The errors came from "make". The configure of the code works fine. My system is: Ubuntu 9.04 + gnuradio 3.2.2 + USRP2 + XCVR2450. I did the installation before, was successfully on USRP2. Not sure what happened this time. :( Many thanks for any advice -- Regards, Guanbo ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
[Discuss-gnuradio] Re: Strange constellation appears on pi/4 dqpsk and dqpsk thru scope_sink
Hi, I also have the similar problem at the receiver side, when trying to obtain the constellation of DQPSK. >From constellation sink block, I can obtain much better constellation. But, using scope sink, it shows a mess. As far as I went through the code of constellation sink, it seems like conducting additional synchronization before plotting the results. Anyone can explain more about the detail of constellation sink in GRC block? And how can we output the data in constellation sink? Many thanks -- Regards, Guanbo ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
[Discuss-gnuradio] Re: Strange constellation appears on pi/4 dqpsk and dqpsk thru scope_sink
Hi, I also have the similar problem at the receiver side, why trying to obtain the constellation of DQPSK. >From constellation sink block, I can obtain much better constellation. But, using scope sink, it shows a mess. As far as I went through the code of constellation sink, it seems like conducting additional synchronization before plotting the results. Anyone can explain more about the detail of constellation sink in GRC block? And how can we output the data in constellation sink? Many thanks -- Regards, Guanbo ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
[Discuss-gnuradio] USRP python problem
Hi, I am trying to output the data of constellation sink to a file. Since constellation sink has some synchronization process in the block, which shows me a better constellation points compared to scope. My gnuradio version is: V3.2.2. The constellation python code is located at: /usr/lib/python2.6/dist-packages/gnuradio/wxgui/constsink_gl.py At the sink of constsink_gl code, it seems like trying to output the I & Q information to the queue, name "msgq" at line 96. The result I output is: How can I output the value before plotting in the window? Many thanks for any suggestions! -- Regards, Guanbo ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
[Discuss-gnuradio] carrier offset in USRP2+2.4/5GHz daugherboard
Hi, I tried to obtain the carrier offset by using the PLL block in GRC. The transmitter is the Zigbee radio at 2.4GHz. Then, the signal is downconverted in USRP2 souce. Two are connected by SMA cable. As shown in the result, the frequency offset can be as large as 200KHz. Is it correct? >From the standard and datasheet, it seems like 10-20ppm tolerance for USRP2, and 40ppm for Zigbee device. But I am still not sure why such large offset appears. I will appreciate for any suggestions! Many thanks -- Regards, Guanbo ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
[Discuss-gnuradio] constellation sink block in GRC
Hi, Anything knows how to set up the parameters at Constellation sink in GRC, eg., theta, Alpha, max frequency, Mu, I am doing some basic tests in GRC+two USRP2, trying to see how the constellation look like. But it does not show good for DBPSK/DQPSK. especially at RX, after downconverting from high frequency(2.4GHz), it seems to shows NOTHING but noise..But read from FFT sink, it did show the signal. I tried to find some documents on gnuradio+GRC, but nothing much on that. Thanks -- Regards, Guanbo ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
[Discuss-gnuradio] USRP2 signal generator and Zigbee radio
Hi, I am trying to use USRP2 to generating the Gaussian noise, specifically "usrp2_siggen_gui.py" and "usrp2_siggen.py". I want to evaluate the performance of TmoteSky under different noise levels. Here comes the problem: By combining the Zigbee signal from TmoteSky sensor(transmitter) and noise generated by USRP2, the receiver node can not decode any bits, even the generated noise is very low. While, if remove USRP2 noise, the decoded bits come back. * My understanding is: it seems like Zigbee signal is buried by USRP2 noise samples. Does it because USRP2 generate the noise in much higher sampling rate?* Tmotesky node: packet rate is 000 per sec; bandwidth: 2MHz, Central Frequency: 2.48GHz USRP2 noise generator Clock rate: 100 MHz Interpolation rate: 32 sampling rate 3.125MHz -- Regards, Guanbo ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
[Discuss-gnuradio] cgran.org down?
Hi, I am looking for some examples in Cgran.org. But I can not log in recently. Is it down? or no longer open to all? Thanks, -- Regards, Guanbo ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
