On Thu, Jul 24, 2008 at 12:30 PM, Nikhil <
address@hidden> wrote:
> Are you trying to measure the impulse response of the channel? If so, then
> one technique would be to transmit a known pseudo-random bit sequence (an
> m-sequence) using BPSK modulation at the carrier frequency of interest. The
> chip rate of the sequence determines the measurement system bandwidth, while
> the sequence length determines the 'dynamic range' of the measurement.
>
> At the receiver set the LO to the same carrier frequency as that at the
> transmitter. Here you need to cross-correlate the equivalent low-pass
> received signal with the known m-sequence to give the (complex) impulse
> response of the channel. Any 'peaks' that exceed your definition of a
> threshold noise level would be your channel coefficients in the time domain.
This is actually implemented in gr-sounder.