Re: [Discuss-gnuradio] USRP Basics questions
Hi Josh, on the SMA connectors I had connected my transmit receive antennas. I wanted to know if while transmitting and receiving signals using USRP sink and source blocks, can I silmatenously probe any pin on the transmit/receive daughter board inorder to see the signal out and in to USRP. Also I was trying to make an OFDM system by implementing the following blocks: Random Source:OFDM Modulator:USRP Sink [Minimum=0; [ Modulation:8 QAM [Unit Number=0 Maximum=2; FFT Length=512 Interpolation=400 Num Samples=1M Occupied tones: 200 Frequency=100M Repeat=Yes] CP Length: 128 Gain=0 Pad for USRP=Yes Side=Side A] Payload length=0] After running this, when I probed pin tx0 - tx7 on the daughter board, I was able to see some waveforms on the scope. But when I build the receiver system: USRP Source:---OFDM DeModulator:FFT Sink [Unit Number=0 [ Modulation:8 QAM Decimation=400 FFT Length=512 Frequency=100M Occupied tones: 200 Gain=0 CP Length: 128 Side=Side A RX Antenna=RXA ] I am get the following warning: ** (python:4085): WARNING **: IPP request failed with status 1030 Timeout and now if i probe the same pins on the daughter board, I am not able to see any waveforms. Can you please help me to figure out this behaviour. Thanks Rgards, Somya Ajmera --- On Tue, 14/4/09, Josh Blum j...@joshknows.com wrote: From: Josh Blum j...@joshknows.com Subject: Re: [Discuss-gnuradio] USRP Basics questions To: ajmeraso...@yahoo.com Cc: 'discuss-gnuradio@gnu.org' discuss-gnuradio@gnu.org Date: Tuesday, 14 April, 2009, 9:57 AM Somya Ajmera wrote: HI Josh, we have basic TX , RX daughter board with us. also what is that range you have mentioned into your reply is for? Many times, users give the usrp sink numbers between +/- 1.0 and there is no transmit power. Just to double check, you should be giving usrp numbers around +/- 10e3 :-) As far as how you can see the signal: You can hook up an oscilloscope to one of the SMA connectors on the basic TX (TXA or TXB) Or, connect the basic RX to the basic TX with SMA to SMA connector, and use a program like usrp_oscope.py or usrp_fft.py to look at the received signal. -Josh Get your new Email address! Grab the Email name you#39;ve always wanted before someone else does! http://mail.promotions.yahoo.com/newdomains/aa/___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
Re: [Discuss-gnuradio] USRP Basics questions
You want to probe the SMA connectors. The pins tx0-tx7 are digital control lines. If you see any signal on the control lines, it is probably very weak leakage from the DAC. Somya Ajmera wrote: Hi Josh, on the SMA connectors I had connected my transmit receive antennas. I wanted to know if while transmitting and receiving signals using USRP sink and source blocks, can I silmatenously probe any pin on the transmit/receive daughter board inorder to see the signal out and in to USRP. Also I was trying to make an OFDM system by implementing the following blocks: Random Source:OFDM Modulator:USRP Sink [Minimum=0;[ Modulation:8 QAM [Unit Number=0 Maximum=2; FFT Length=512 Interpolation=400 Num Samples=1MOccupied tones: 200 Frequency=100M Repeat=Yes] CP Length: 128Gain=0 Pad for USRP=Yes Side=Side A] Payload length=0] After running this, when I probed pin tx0 - tx7 on the daughter board, I was able to see some waveforms on the scope. But when I build the receiver system: USRP Source:---OFDM DeModulator:FFT Sink [Unit Number=0[ Modulation:8 QAM Decimation=400FFT Length=512 Frequency=100M Occupied tones: 200 Gain=0CP Length: 128 Side=Side A RX Antenna=RXA ] I am get the following warning: ** (python:4085): WARNING **: IPP request failed with status 1030 Timeout You can ignore this, its just wxpython molesting your printers. and now if i probe the same pins on the daughter board, I am not able to see any waveforms. Can you please help me to figure out this behaviour. Thanks Rgards, Somya Ajmera ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
Re: [Discuss-gnuradio] USRP Basics questions
Hello, Does anyone has some discription about the two programs usrp_fft.py and usrp_oscope.py? I try to search in the archive but didn't find any basic discriptions. For example, I'm using digital-bert benchmark_tx.py to transmit a sequence of 1's, which modulated by BPSK; on the other computer, I use python usrp_fft.py -f 900M -T B -R TX/RX -d 32 to display the output. I've some signals at the center frequency, but I don't know whether it is the signals at the transmitter side usrp or signals received in the other usrp? Similar question to usrp_oscope.py as well, and I also wonder what do the two lines mean, the red one and the blue one? Thanks in advance. Your help is highly appreciated. ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
[Discuss-gnuradio] USRP Basics questions
Hi All, I was wondering about some basic functions of the USRP board: 1) To what carrier frequency does the USRP board (specifically AD9862) up converts the base band signal and how can we change that? 2) At what transmission power does the USRP board transmits? and how that can be controlled or regulated? 3) While using GRC, when we transmit the signal using the USRP block, how can we check or see the transmitted signal? Is there any pin on the USRP board which can be probed with the oscilloscope in order to view the transmitted signal. Any help is really appreciated, Thanks Regards, Somya Ajmera New Email names for you! Get the Email name you#39;ve always wanted on the new @ymail and @rocketmail. Hurry before someone else does! http://mail.promotions.yahoo.com/newdomains/aa/___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
Re: [Discuss-gnuradio] USRP Basics questions
3) While using GRC, when we transmit the signal using the USRP block, how can we check or see the transmitted signal? Is there any pin on the USRP board which can be probed with the oscilloscope in order to view the transmitted signal. What daughterboards do you have? Make sure that the amplitude of the signal going into usrp sink is on the order of 10,000 (since usrp range is +/- 32768) -Josh ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
Re: [Discuss-gnuradio] USRP Basics questions
HI Josh, we have basic TX , RX daughter board with us. also what is that range you have mentioned into your reply is for? Thanks Regards, Somya Ajmera --- On Tue, 14/4/09, Josh Blum j...@joshknows.com wrote: From: Josh Blum j...@joshknows.com Subject: Re: [Discuss-gnuradio] USRP Basics questions To: ajmeraso...@yahoo.com Cc: 'discuss-gnuradio@gnu.org' discuss-gnuradio@gnu.org Date: Tuesday, 14 April, 2009, 4:37 AM 3) While using GRC, when we transmit the signal using the USRP block, how can we check or see the transmitted signal? Is there any pin on the USRP board which can be probed with the oscilloscope in order to view the transmitted signal. What daughterboards do you have? Make sure that the amplitude of the signal going into usrp sink is on the order of 10,000 (since usrp range is +/- 32768) -Josh Get your new Email address! Grab the Email name you#39;ve always wanted before someone else does! http://mail.promotions.yahoo.com/newdomains/aa/___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
Re: [Discuss-gnuradio] USRP Basics questions
Somya Ajmera wrote: HI Josh, we have basic TX , RX daughter board with us. also what is that range you have mentioned into your reply is for? Many times, users give the usrp sink numbers between +/- 1.0 and there is no transmit power. Just to double check, you should be giving usrp numbers around +/- 10e3 :-) As far as how you can see the signal: You can hook up an oscilloscope to one of the SMA connectors on the basic TX (TXA or TXB) Or, connect the basic RX to the basic TX with SMA to SMA connector, and use a program like usrp_oscope.py or usrp_fft.py to look at the received signal. -Josh ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
