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How to use Two RX in osmocom

Posted: Wed Apr 03, 2019 10:58 pm
by zhanlguy
I am trying to record dvbt signal by using bladerf.

Anyone knows how to use two RX channels? please in details

thanks

Re: How to use Two RX in osmocom

Posted: Sat Apr 06, 2019 1:56 am
by robert.ghilduta
You need to double click the gr-osmosdr source block and in the "Device Arguments" field enter "bladerf=0,nchan=2" and scroll down a bit to "Num Channels" and select 2. Once you click "OK" you should see two output ports.

Re: How to use Two RX in osmocom

Posted: Tue Jul 14, 2020 7:02 am
by BennoTr
Sorry to hijack this old thread, but I have also troubles to us two RX channels with the osmocom source block.

I set the Device Arguments to "bladerf=0,nchan=2" and Num Channels to 2. I also set Ch0: Frequency to 2404e6 and Ch1: Frequency to 2452e6, Bandwidth is set on both channels to 2e6 and the Sample Rate is 4e6.

But I get on both channels nearly the same signal and if I change the frequency of one channel the signal of the other channel is also affected.

What do I do wrong?


Thanks!

Re: How to use Two RX in osmocom

Posted: Fri Jul 17, 2020 1:09 pm
by Jose.Amador95
Hi BennoTr! As far as I know, both channel pairs (TX1&TX2 and RX1&RX2) share the same LO, meaning that the mixer cannot be set to independent frequencies in a single direction. I may have read that this constraint is somewhat flexible up to ~50 MHz in other thread on this forum, but I'm not sure.

Re: How to use Two RX in osmocom

Posted: Tue Aug 11, 2020 11:12 pm
by zhanlguy
Hi all

Thank you for the reply.

My experiment device is BladeRF A9, which has two receiver connections named RX1 and RX2.

I can record the two channel signal in the same time, right now.

I am working on the experiment of Passive radar by using SDR that I need to collect the two channel signal in the same time.

However, the signal recorded in RX2 seems not right, so there must be some problem with it. Anyone can help to solve this problem?

Much appreciated.

Re: How to use Two RX in osmocom

Posted: Thu Aug 13, 2020 10:29 pm
by zhanlguy
robert.ghilduta wrote: Sat Apr 06, 2019 1:56 am You need to double click the gr-osmosdr source block and in the "Device Arguments" field enter "bladerf=0,nchan=2" and scroll down a bit to "Num Channels" and select 2. Once you click "OK" you should see two output ports.
Hi Robert

Thank you for the reply, I am wondering is there anyway, I can use osmocom_fft command to operate the two channel recording?