Zynq SDR Capture Length question!

While using Zynq SDR, the capture length can not exceed '16777216'.

I want to capture length longer than the prescribed. I get the following error.

Error using comm.libiio.AD9361.rx/capture

Requested capture length (23592960 Samples) exceeds maximum value for this number of channels

(16777216 Samples). Use 'EnableOversizeCapture' to risk compromising data contiguity in return for a

larger capture length.

How to use 'EnableOversizeCapture in order to capture longer length than the one prescribed.

Thanks.

Answer 1

[Jyotsna Talluri]

You can just enable the property'EnableOversizeCapture' by setting it to true.In addition to the other arguments of capture function,specify it as a name -value pair.

capture(rxsdr,'EnableOversizeCapture',true);

Refer to the below documentation link for more information

https://www.mathworks.com/help/supportpkg/plutoradio/ref/plutoradio.sdrrxpluto.capture.html#namevaluepairs

[jarul]

Thanks for your quick response. I do appreciate your help.

Answer 2

[jarul]

I have another question related to the above issue.

When I tried to transfer rather large size, I get the following error.

Generating WLAN transmit waveform:

Error using comm.libiio.AD9361.tx/validateInputsImpl

The maximum samples per frame for the selected channel mapping is 16777216.

Error in comm.libiio.AD9361.tx/transmitRepeat

Error in OFDM_SIM1 (line 189)

sdrTransmitter.transmitRepeat(txWaveform);

How do I overcome the above error? It seems to me that I can not have the samples per frame more than 16777216.

[Neil MacEwen]

Hi Jarul,

Both transmitRepeat and capture methods use on-board storage, which is size-limited. When you select "EnableOversizeCapture" you are choosing to stream data to the host, instead of capturing it on on-board storage first - this is why you are no longer guaranteed contiguity, as you may lose samples over the Ethernet link.

Likewise, on the transmit side, the only way you can send a frame of a size larger than the 16M limit is by attempting to stream in real-time from the host, instead of using transmitRepeat. Again, you will not be guaranteed contiguity, and are likely to see performance issues (dropped samples).

Thanks,

Neil

[jarul]

Thanks for your response. Appreciate very much!