Re: [Discuss-gnuradio] RSSI estimation

Thanks Devin and Matt. >From your reply can I say if I don't use AGC and with a fixed value of gain, then I can calculate the RSSI value. Bin Zan On Tue, Apr 27, 2010 at 3:26 PM, devin kelly wrote: > Hello Bin, > > My group considered doing this about 4-5 months ago.

[Discuss-gnuradio] RSSI estimation

Hello, Anyone know if it is correct to roughly estimate RSSI information from I/Q values. For example is it correct to say RSSI of a message is equal to 10log10(I^2-Q^2). Otherwise, what is the correct way to obtain RSSI value in gnuradio? Thanks, Bin Winlab

Re: [Discuss-gnuradio] running OFDM on USRP2

Of Tom Rondeau > Sent: Thursday, 4 February 2010 11:56 PM > To: bin zan > Cc: discuss-gnuradio@gnu.org > Subject: Re: [Discuss-gnuradio] running OFDM on USRP2 > > On Wed, Feb 3, 2010 at 1:55 PM, bin zan wrote: > > Hi Tom, > > In our case, even with script from Veljko

[Discuss-gnuradio] Re: create-gnuradio-out-of-tree-project

ender side ( I only see one c++ execute file looks like transmit something under that directory). Please advise which files I should start with. Thank you, Bin Zan Winlab, Rutgers. On Tue, Mar 16, 2010 at 1:36 PM, Eric Blossom wrote: > On Thu, Mar 11, 2010 at 01:44:04PM -0500, bin zan wrote

[Discuss-gnuradio] create-gnuradio-out-of-tree-project

inZan/usrp2_oot/python$ ./qa_usrp2_oot.py Traceback (most recent call last): File "./qa_usrp2_oot.py", line 24, in import usrp2_oot_swig ImportError: No module named usrp2_oot_swig Thanks, Bin Zan Winlab, Rutgers ___ Discuss-gnuradio maili

Re: [Discuss-gnuradio] question about ofdm subcarrier-mapping

Thanks Tom, your information completely answered my question. In my case, the subcarriers start from 1, I guess that's why there will be 1 number difference. Thanks for your time, Bin On Thu, Feb 18, 2010 at 11:11 AM, Tom Rondeau wrote: > On Wed, Feb 17, 2010 at 4:48 PM, bin zan wrote

[Discuss-gnuradio] question about ofdm subcarrier-mapping

Hi, For a fft-length 64, occupied-tones 32 ofdm mapping will actually use subcarrier (16-30) and (33-47) according to the code. However, when I plot the results from ofdm_receiver-fft_out_c.dat, I find it will have a peak at subcarrier 33 always, and the occupied tone seems start from 16 and en

Re: [Discuss-gnuradio] Using OFDM

You can start from gnuradio-example/src/python/benchmark_ofdm_tx.py or benchmark_ofdm_rx.py. Bin 2010/2/12 Christian Pérez > Hello, I'm a begginer in GNU Radio and I need use the OFDM block. There is > a OFDM.py (ofdm modulator and demodulator), but I don't kwon how use them > and the examples a

Re: [Discuss-gnuradio] question about gr_ofdm_sampler.cc

Hi Tom, > Well then, yes, it is modified. Since the data are changed, can I say if measure the SNR from the data after FFT, then they are inaccurate and bias? Thanks, Bin On Thu, Feb 11, 2010 at 2:04 PM, Tom Rondeau wrote: > On Thu, Feb 11, 2010 at 6:52 AM, bin zan wrote:

Re: [Discuss-gnuradio] question about gr_ofdm_sampler.cc

data) to the FFT bins? Thank you, Bin On Thu, Feb 11, 2010 at 12:16 AM, Tom Rondeau wrote: > On Wed, Feb 10, 2010 at 8:46 PM, bin zan wrote: > > > > > > On Wed, Feb 10, 2010 at 10:18 PM, bin zan wrote: > >> > >> Hi Tom, > >> Thanks a lot for all y

Re: [Discuss-gnuradio] question about gr_ofdm_sampler.cc

Wed, Feb 10, 2010 at 10:18 PM, bin zan wrote: > Hi Tom, > Thanks a lot for all your information. > Can I say that the predefined preambles are used both for symbol sync and > then later correlation, and the CP is only used for symbol sync? > One preamble is inserted at transmi

Re: [Discuss-gnuradio] question about gr_ofdm_sampler.cc

Rondeau wrote: > On Wed, Feb 10, 2010 at 11:40 AM, bin zan wrote: > > Hi Tom, > > Can you help me answer the following questions? > > 1. Does that mean, the data has not be divided into sync'd > > segments until ofdm_sampler.cc? > > I

Re: [Discuss-gnuradio] question about gr_ofdm_sampler.cc

36 PM, Tom Rondeau wrote: > On Wed, Feb 10, 2010 at 8:10 AM, bin zan wrote: > > Hi, > > I just wonder why in gr_ofdm_sampler.cc, the consume_each for > > STATE_NO_SIG and STATE_PREAMBLE are different. > > consume_each(index - d_fft_length + 1); > > consume_

[Discuss-gnuradio] question about gr_ofdm_sampler.cc

Hi, I just wonder why in gr_ofdm_sampler.cc, the consume_each for STATE_NO_SIG and STATE_PREAMBLE are different. consume_each(index - d_fft_length + 1); consume_each(index-d_fft_length); Both suppose to leave one fft length, right? Can any one explain it? Thanks, Bi _

[Discuss-gnuradio] the gnuradio ofdm receiver

Hi, 1.Any one can tell me in gnuradio OFDM, after ofdm_sync block, what are the data looks like? 2. Does the output go through FFT operation already? If not, when does the FFT actually actually come ? Does it after the ofdm_sampler block? If yes, how can I actually get these data? And, how can I

Re: [Discuss-gnuradio] running OFDM on USRP2

Hi Tom, In our case, even with script from Veljko, the OFDM receiver doesn't show any thing. And we always see "usrp2: failed to enable realtime scheduling". Do you think that will cause problem? Thanks, Bin On Wed, Feb 3, 2010 at 12:57 PM, Anupama Purohit wrote: > Hi Tom , > Thanks , we did try

Re: [Discuss-gnuradio] running OFDM on USRP2

benchmark_ofdm_rx.py -f 2.4G -d 256 --fft-length=64 > --occupied-tones=32 --cp-length=4 > > And it works fine. > When I tested the example I played with tx and rx gains and the > tx-amplitude to find the best setting. > > Cheers, > > Veljko > > 2010/1/27 bin zan :

[Discuss-gnuradio] running OFDM on USRP2

Hello, I was trying to run following OFDM command on USRP2, however, I got a bunch of "Stime out" at the receiver side. ./benchmark_ofdm_tx.py -f 2.4G -i 512 --fft-length=64 --occupied-tones=32 --cp-length=4 ./benchmark_ofdm_rx.py -f 2.4G -d 256 --fft-length=64 --occupied-tones=32 --cp-

[Discuss-gnuradio] free slots

Hi, I free the grid slots from 8:00pm to 10:00pm tonight. Bin ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio

[Discuss-gnuradio] question about usrp_rx_cfile.cc

Hi, Any one know that the signal data collected by usrp_rx_cfile.cc is downconversion baseband signal or not? Thanks, Bin Zan ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio

[Discuss-gnuradio] question regard to gr_multiply_cc

Can anyone here explain what does gr_multiply_cc.cc::work do as a part of ofdm receiver process? Thanks, Bin ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio

[Discuss-gnuradio] question about gr_fft_filter_ccc.cc

Hi, I found ofdm receiver will go through the file gr_fft_filter_ccc.cc. Anyone can explain what does this file do? What is d_xformed_taps? Thanks, Bin BTW, I believe "gr_fft_vcc_fftw.cc" is where the IFFT and FFT happens for transmitter and receiver.

[Discuss-gnuradio] OFDM IFFT question

Hi, I found the OFDM IFFT caculation is very different from what I got in MATLAB. In detail, my command is shown below ./benchmark_ofdm_tx.py -f 10M -i 512 --fft-length=64 --occupied-tones=32 --cp-length=4 (bpsk) The packet size is 8 bits, after a serials of operation, it added 4 bytes in

[Discuss-gnuradio] How does ofdm sync work

Hi, Does any one know how does ofdm in gnuradio do sync? What I found in the gr_ofdm_frame_sink.cc is just check sig[0], which is just the second bytes of input_items. However, I didn't see any reason that the (const char *) input_items[1] will be NULL. Thanks, Bi

[Discuss-gnuradio] Can we really put whatever rx_cfile obtained into ofdm receiver?

Hi, I am going to give more detail about my experiment in case some one could help me but didn't understand my situation. sender: step 1.a : ./benchmark_ofdm_tx.py -f 10M -i 512 --fft-length=32 --occupied-tones=16 --cp-length=4 receiver: step 1.b: ./usrp_rx_cfile.py -f 10M -d 256 ofd

[Discuss-gnuradio] Re: use a file as source to the ofdm receiver

cc" however, I observed that in "gr_ofdm_frame_sink.cc", the data are totally changed. Does anyone what happened in between? Thank you, Bin On Thu, Oct 1, 2009 at 3:56 PM, bin zan wrote: > Hi, > I am using ./usrp_rx_cfile.py collecting ofdm signals into a file. Th

[Discuss-gnuradio] use a file as source to the ofdm receiver

Hi, I am using ./usrp_rx_cfile.py collecting ofdm signals into a file. Then I use it as import into a ofdm receiver {self.u = gr.file_source(gr.sizeof_gr_complex, "data.dat", False)...} , the method followed by the website " http://www.mail-archive.com/discuss-gnuradio@gnu.org/msg20498.html";

Re: [Discuss-gnuradio] can usrp_rx_cfile.py be used to collect ofdm signal?

ead_complex_binary.m or use it for further processing. > > Cheers, > > Christoph > > > > > Hello, > > Does anyone know if use 'usrp_rx_cfile.py' to collect ofdm signal > will > > be any problem? In other words, after

[Discuss-gnuradio] can usrp_rx_cfile.py be used to collect ofdm signal?

Hello, Does anyone know if use 'usrp_rx_cfile.py' to collect ofdm signal will be any problem? In other words, after collection, is it possible to decode these signals? Thanks, Bin Zan ___ Discuss-gnuradio mailing list Discuss-gnuradio@gn

[Discuss-gnuradio] How to inject fake ofdm data into the gnuradio procedure

Hi all, I have a bunch of complex numbers which are received at an ofdm receiver at earlier time. Later, I would like to insert these numbers into ofdm procedure on gnuradio. Anyone knows which place or which file is the better place I can do that? Thanks, Bin _

Re: [Discuss-gnuradio] how to reduce data rate in OFDM

1) What radio hardware are you using? Just Basic Tx/Rx 2) What PC hardware are you using? PC with a 1 GHz VIA C3 processor, 512 MB of RAM, 20 GB of local disk 3) Are you seeing output similar to the following "uUuUuUuUuUuUuUuUuOuOuUuOu" ? Yes, uOuO 4) Are you using 2 separate PCs for the tx/r

[Discuss-gnuradio] How to change Sample per symbol rate in OFDM?

Does any one know what is the sample per symbol rate in OFDM gnuradio? Or how to change the value? Thanks, bin ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio

[Discuss-gnuradio] how to reduce data rate in OFDM

suggestion? ./benchmark_ofdm_rx.py -f 40M -d 256 --fft-length=32 --occupied-tones=16 --cp-length=2 ./benchmark_ofdm_tx.py -f 40M -i 512 --fft-length=32 --occupied-tones=16 --cp-length=2 Thanks, Bin Zan ___ Discuss-gnuradio mailing list Discuss-gnuradio@gn

[Discuss-gnuradio] about ofdm

Hi all, I was trying to cut a packet into several pieces and send them through ofdm. I force the transmitter use only certain sub-carriers, for example first 64 sub-carriers. However, at the receiver side, I found it only can receive first piece of packet correct, and never receive the remai

Re: [Discuss-gnuradio] gnuradio debug with gnuradio ofdm

Thanks, Eric. However, there must something wrong. Because it says fusb::_reap: Interrupted system call. Without gdb, it will go through more stuff. Any idea? Thanks, Bin On Fri, Aug 14, 2009 at 1:48 PM, Eric Blossom wrote: > On Thu, Aug 13, 2009 at 01:52:12PM -0400, bin zan wrote: > &

[Discuss-gnuradio] gnuradio debug with gnuradio ofdm

Hello, I was trying to use gdb with ofdm example. I called gri_debugger_hook in gr_ofdm_frame_sin.cc :work. However, it gives following output which is not what I expected. Can any one give me a help or explanation? Thanks, Bin # /root/gnuradio-3.