Re: [Discuss-gnuradio] benchmark_rx.py segmentation fault

2015-05-01 Thread Henry Jin
I remember I had the same issue before when testing the benchmark. What I did to avoid the crash is to start the tx first, and then the rx. It seems that you are doing it in reverse order, which is reasonable but not working according to my test. On Fri, May 1, 2015 at 10:51 AM, Richard Bell wrot

Re: [Discuss-gnuradio] OFDM test with USRP

2015-03-19 Thread Henry Jin
Hi Martin, Thanks for the FOSDEM 14 video on youtube (although maybe not posted by you). Your talk is very informative and helpful. On Thursday, March 19, 2015, Martin Braun wrote: > On 19.03.2015 14:11, Henry Jin wrote: > >> Hi Marcus, >> >> I later added a throttle

Re: [Discuss-gnuradio] OFDM test with USRP

2015-03-19 Thread Henry Jin
Henry On Thu, Mar 19, 2015 at 10:17 AM, Henry Jin wrote: > Hi Marcus, > > Thanks for your very detailed comments. > > My purpose of testing the PER is to facilitate evaluations on further > modifications of the codes. I'd like to set up a benchmark like the ones I > ha

Re: [Discuss-gnuradio] OFDM test with USRP

2015-03-19 Thread Henry Jin
ure, was too lazy to look into the source code just now) that the OFDM implementation (you're using the older one, the newer one is cooler) doesn't do much on the receiving side to recover the signal. Have a look at the rx_ofdm example (in /usr/[local/]share/gnuradio/examples/digital/, or so

[Discuss-gnuradio] OFDM test with USRP

2015-03-18 Thread Henry Jin
Hi everyone, I have built a tx and a rx grc flowchart for OFDM using USRP. I found the range of the amplitude of the input is fairly small in order to get it working (i.e., the USRP at the rx end can successfully decode the packets.) I wound if anyone can share some thoughts about this? I've been

[Discuss-gnuradio] SNR estimation for QAM modulation

2014-01-24 Thread Henry Jin
Hi all, I'm wondering if SNR estimation by using the probe_mpsk_snr_est_xx can be applied to QAM modulation as well? I checked the source code and found nothing specific tied to MPSK modulation. Also, I found Tom has a blog about SNR estimator years ago http://www.trondeau.com/grcon12-hackfest/201

Re: [Discuss-gnuradio] About DPSK mod and demod

2014-01-10 Thread Henry Jin
course, since we have to add some customized modules, the best way is to directly work on the python script. Best Henry On Tue, Dec 3, 2013 at 10:00 PM, Henry Jin wrote: > Hi, > > I tried to build a simple flow graph of DPSK modulation and demodulation. > The result is verified using th

Re: [Discuss-gnuradio] About DPSK mod and demod

2013-12-14 Thread Henry Jin
..r. > > bytes_sent file has 999424 bytes > and bytes_received has 995328 bytes. > The difference is probably that 1 million samples from random source isnt > even to the payload length of packet encoder. > > > On Sun, Dec 8, 2013 at 8:57 PM, Henry Jin wrote: > >> Hi all, >

Re: [Discuss-gnuradio] Bit error rate test

2013-12-12 Thread Henry Jin
hough. Anyone has any thoughts on this? Henry Date: Thu, 12 Dec 2013 09:26:48 +0100 From: "Martin Braun (CEL)" On Wed, Dec 11, 2013 at 04:15:11PM -0700, Henry Jin wrote: > I tried to use digital_bert_tx.py and digital_bert_rx.py to test the BER > performance of different modulatio

[Discuss-gnuradio] Bit error rate test

2013-12-11 Thread Henry Jin
Hi I tried to use digital_bert_tx.py and digital_bert_rx.py to test the BER performance of different modulations. The command I use is ./digital_bert_tx.py --tx-freq=5.1e9 --tx-gain=30 -S 8 --mod-code=gray -m bpsk. The results for BPSK is good enough. When SNR is above 20, the BER is around 10^(-1

Re: [Discuss-gnuradio] About DPSK mod and demod

2013-12-08 Thread Henry Jin
erstood, I attached a screenshot comparing the two files from file sinks. https://www.dropbox.com/s/9203fvigi3wohmh/Screenshot%20from%202013-12-08%2021%3A52%3A48.png Please give me some suggestions if you have any thoughts. Thanks. Henry On Thu, Dec 5, 2013 at 2:39 PM, Henry Jin wrote: > Th

Re: [Discuss-gnuradio] About DPSK mod and demod

2013-12-05 Thread Henry Jin
rying to do. > Sorry I couldn't be of more help. > > Michael > > > On Wed, Dec 4, 2013 at 1:31 PM, Henry Jin wrote: > >> On Wed, Dec 4, 2013 at 12:13 PM, Michael Berman >> wrote: >> >>> Looking at your flowchart in the original post, you

Re: [Discuss-gnuradio] About DPSK mod and demod

2013-12-04 Thread Henry Jin
random source. This may > help with keeping the data a little more somewhat aligned. > > *Yes, this could make things clearer. But maybe it makes no difference. I remember in one of Tom's tutorial, he said as long as there is one throttle in the flow, then all the units are throttled.*

Re: [Discuss-gnuradio] About DPSK mod and demod

2013-12-04 Thread Henry Jin
> encoding. > > --n > > > On Tue, Dec 3, 2013 at 9:00 PM, Henry Jin wrote: > >> Hi, >> >> I tried to build a simple flow graph of DPSK modulation and demodulation. >> The result is verified using the Error Rate module. The link shows the flow >> I&

[Discuss-gnuradio] About DPSK mod and demod

2013-12-03 Thread Henry Jin
Hi, I tried to build a simple flow graph of DPSK modulation and demodulation. The result is verified using the Error Rate module. The link shows the flow I'm using. https://www.dropbox.com/s/jwmmttyi4es4alf/Screenshot%20from%202013-12-03%2021%3A50%3A58.png I know that the output of demod module