[USRP-users] E312 Two Transmit Channel and One Receive Channel

Xingjian Chen xingjian at umass.edu
Fri Mar 22 10:25:23 EDT 2019


I used a modified Siggen RFNOC block generating sine waves. The first one is an external loopback from tx 1 to rx 1. The second plot is still an external loopback from tx1 to rx1 but tx2 is also transmitting. The third plot is the Vivado debug plot in a custom RFNOC block which is connected to receiver radio when tx1 tx2 rx1 are working at same time.


Microwave Remote Sensing Laboratory

Electrical and Computer Engineering

University of Massachusetts, Amherst

Ph.D. Student

Xingjian Chen


________________________________
From: Girolamo Savonarola <iw8fby at gmail.com>
Sent: Friday, March 22, 2019 7:57
To: Xingjian Chen
Subject: Re: [USRP-users] E312 Two Transmit Channel and One Receive Channel

can you explain to me how did you make those screens appear? thank you

Il giorno gio 21 mar 2019 alle ore 21:08 Xingjian Chen via USRP-users <usrp-users at lists.ettus.com<mailto:usrp-users at lists.ettus.com>> ha scritto:
Dear all,
I am trying to use two tx channels and one rx channel at the same time. Now, I can do 1 tx and 1 rx work at the same time no matter which tx channel I use. However, I cannot make 2 tx channels working with 1 rx properly. I narrow down to a point that in my cpp control file in host computer. As long as I set both tx channel for the streamer to true, the received signal becomes 1/4 cycle. Please check the pictures below or in the attachment.

    tx_radio_ctrl->set_tx_streamer(true, tx_chan);
    tx_radio_ctrl->set_tx_streamer(true, tx_chan_1);
    rx_radio_ctrl->set_rx_streamer(true, rx_chan);

When I check in the FPGA code in the receiving chain, I see that the m_axis_data_tvalid is switching between high and low. I am wondering if there is any way to set up in cpp or host computer such that forcing the rx radio to keep streaming without any break when using 2 tx channels? I tried uhd::stream_cmd_t stream_cmd(uhd::stream_cmd_t::STREAM_MODE_START_CONTINUOUS);
but no luck. Thank you in advance!

[cid:169a5434966f456b1e51]
[cid:169a5434967f456b1e52]
[cid:169a5434967f456b1e53]

_______________________________________________
USRP-users mailing list
USRP-users at lists.ettus.com<mailto:USRP-users at lists.ettus.com>
http://lists.ettus.com/mailman/listinfo/usrp-users_lists.ettus.com
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.ettus.com/pipermail/usrp-users_lists.ettus.com/attachments/20190322/7615b112/attachment.html>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: pastedImage.png
Type: image/png
Size: 67306 bytes
Desc: pastedImage.png
URL: <http://lists.ettus.com/pipermail/usrp-users_lists.ettus.com/attachments/20190322/7615b112/attachment.png>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: pastedImage.png
Type: image/png
Size: 69120 bytes
Desc: pastedImage.png
URL: <http://lists.ettus.com/pipermail/usrp-users_lists.ettus.com/attachments/20190322/7615b112/attachment-0001.png>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: pastedImage.png
Type: image/png
Size: 69609 bytes
Desc: pastedImage.png
URL: <http://lists.ettus.com/pipermail/usrp-users_lists.ettus.com/attachments/20190322/7615b112/attachment-0002.png>


More information about the USRP-users mailing list