Signal Feedback Cancellation

Started by eeh August 22, 2005

I am going to do a research project which needs to cancel feedback data
signal of an amplifier. The data signal frequency is 10MHz which is not
audio type. I have searched the internet that most of the feedback
algorithm are for audio signal, which allows a little distortion in the
output signal. However, as the input data type is not audio, the output
data must not be distorted in any way.

Could anyone introduce me a feedback signal cancellation algorithm
which meets these criterions? The hardware used could be DSP or FPGA or


I have some idea, but not known whether the direction is OK. Could
someone give me some idea?

I need to make a matched filter of length n to match the input signal
at a defined time, which is the time after sending out nth tap data.

Because of high frequency and long path reflection, the feedback signal
has a phase change, so I need also check the matching within one period
of the signal. If I employ 40MHz sampling, I need to take into account
4 sampling points more (40/10). The matching amplitude is used as a
attentuation factor of matching signal, which is used to substract the
input signal to retrieve the real input signal.