Receiver having an adjustable matched filter

Abstract From the Canadian patent

A radio receiver's digital matched filter (52') is intended to match a pulse-shaping filter (23) in the transmitter whose signals it receives. However the clock, signal on which the matched filter's timing is based is generated by a receiver clock (58') that is independent of the transmitter clock (56) and that is subjected to no timing adjustment to bring the two clock signals into synchronism. So as to ensure that the matched and pulse-shaping filters work together as a Nyquist filter, therefore a timing-recovery, circuit (60') senses the timing offset in the matched filter's output, and a coefficient generator (80) adjusts the matched filter's coefficients in such a manner that the …