comparing modem.oqpsk probability error and ber

Question

hi currently i have the following code in my matlab

        values = [0;1;0;0;1;0;1;0];   % can contain only 0s and 1s
        h = modem.oqpskmod;
        y = modulate(h, values);
        g = modem.oqpskdemod(h);
        z = demodulate(g,y);
        BER = sum(logical(values(:)-z(:)))/numel(values);% thanks to gnovice!

now my question is how can i compare this BER to the Probability Error of the OQPSK?

Answer 1

After you've run a number of different sets of values through the modulation/demodulation process above, the resulting average BER measure is an estimate of the bit-wise probability for an error to occur.

Perhaps you are wanting to compare the above estimate to an actual derived formula for what the expected error rate is? This Wikipedia page says that the probability of bit-error for QPSK (and I assume also for OQPSK) is given by the formula:

Pb = Q(sqrt(2*Eb/N0));

where the function Q and the parameters Eb and N0 are described here.