psk demodulation of signal received via DAQ

[commsengineer]

Hi,

We are trying to implement a basic communications system , where at one point it is required to perform PSK on some binary data , transmit it via speakers and  receive the same via a microphone and perform demodulation on it. 

We are performing this on a PXIe8130 and are using the Data Aquisition assistant(DAQ) to Transmit the data via speakers (voltageoutput) and another DAQ to receive it from a mic( voltage input ). 

we are using the modulation toolkit's "MT modulate PSK" vi for modulation purposes. its output is a complex waveform containing "t0", "dt" and complex data "y".

Questions:

1)  What data should we feed into the Output DAQ ? so far we have been separating the output complex waveform into y,t0 and dt and then transmitting y. but the demodulated data is not matching the transmitted data. Some examples we saw used a "upconvert baseband" vi on y before plotting it . is the same to be used for transmission purposes ?

2) we are using the "MT demodulate PSK" vi for demodulating received data. how does this differ from "mt detect PSK" vi ?

3)to generate the input complex waveform required for the demodulate psk vi , we are taking the dynamic data received from  mic via input DAQ , and then clustering it with "t0" and "dt", where the values of t0 and dt are taken to be the same as they were before transmission(ie the values of t0 and dt of the output complex waveform genrated from modulate psk vi) . Is this correct?

4) What other reasons , if any , could there be for unsuccessful demodulation ?

Thanks in Advance !