How is the number of samples IQ samples calculated while receiving IQ samples from USRP B200?

I am using USRP B200 to collect IQ samples using the code given in the matlab central. The paramerters are as following, duration =10, Master clock rate =35e6, Decimation factor 1, samples per frame= 10,000., sample rate= 35e6, frame duration= 10000 (samples). However in each iteration, the rx() function gives only 362 samples (complex samples). I have used step() function as in QPSK receiver example, then also the number of samples is 362.

Question: As per my understanding each frame should give us 10,000 samples if the iteration corresponds to one frame. Why is the number of samples 362?

function [receiveTime,overrunCount] = sdruReceiveData()
        Duration = 10;
        MasterClockRate = 35e6;
        DecimationFactor = 1;
        SamplesPerFrame = 10000;

        SampleRate = MasterClockRate/DecimationFactor;
        FrameDuration = SamplesPerFrame/SampleRate;
        Iterations = Duration/FrameDuration;

        rx = comm.SDRuReceiver('Platform','B210','SerialNum','30F59A1', ...
                       'MasterClockRate',MasterClockRate, ...
                       'DecimationFactor',DecimationFactor, ...
                       'OutputDataType','double');
        count = 0;
        rx();
        disp('Started Reception...');
        tic
        for i = 1:Iterations
            [data,~,overrun] = rx();
            if overrun
            count = count+1;
            end
        end
        receiveTime = toc;
        overrunCount = count;
        release(rx);
end

Answer 1

[Nadia Shaik]

Hi Sreejith,

I understand that you expect the number of samples per frame to be 10,000.

One possible reason for the samples per frame to be 362 can be because of the default value of "SamplesPerFrame" property. The "SamplesPerFrame" property of "comm.SDRuReceiver" is assigned a default value of 362. You can set it programatically to any desired value while creating the "comm.SDRuReceiver" object.

I hope this helps!