Optimized filter design for PR-QMF based spread spectrum communications

A framework is presented for designing filter banks which are optimized in accordance with properties and constraints dictated by a PR-QMF based spread spectrum communications system. The properties are determined by the requirement of the system to operate in the presence of narrowband (tone) interference. From these properties, an objective function is developed. A design approach, adapted from sub-band image coding, is then employed to provide a numerical method for the filter design by using the objective function in a multivariable optimization problem. The resulting filter bank is implemented in a PR-QMF based spread spectrum system and BER curves are generated through numerical simulation for analysis.