In decoding spread-spectrum BPSK signals in the presence of narrow-band interference, a perfect reconstruction multi-rate bandpass filter bank can be used with a very simple adaptive algorithm to eliminate narrow-band interference broadband signals. Inherent in this structure is the need to do quadrature processing to eliminate images that occur due to the up-sampling required to obtain the narrow-band bandpass filters. We propose to use parallel processors (microprocessors, ASICs, or DSP chips) to implement complex FIR filters needed to eliminate the upsampled images. The processors implement a very simple complex FIR filter in one modulus of a generalized quadratic residue number system (GQRNS). By keeping the moduli small and the filter order low, it is possible to use standard binary within the processor to implement a GQRNS number system. This allows us to obtain the advantages of parallel processing and simplified complex number arithmetic inherent in GQRNS arithmetic while maintaining standard binary arithmetic in the processors.
展开▼