Urgent help required!!!

[Shruti01]

Hi ppl,

In SDR, the RF signal is converted into IF signal by A to D converter. The received signal is a set of sample points. Based on symbol rate/baud rate/bit rate, the received signal has to be identified whether it is amplitude, frequency or phase modulated and decode the original signal if necessary. I mean how to detect whether the received signal is using BPSK, QPSK modulation technique.


Thanx.

 

[kmorgan]

Good article

Hi ppl,

In SDR, the RF signal is converted into IF signal by A to D converter. The received signal is a set of sample points. Based on symbol rate/baud rate/bit rate, the received signal has to be identified whether it is amplitude, frequency or phase modulated and decode the original signal if necessary. I mean how to detect whether the received signal is using BPSK, QPSK modulation technique.


Thanx.

Here's one of the better articles in PDF format that explains demodulation techniques for the I and Q signals generated by SDR.

http://www.nonstopsystems.com/radio/article-sdr-is-qs.pdf