High speed nonlinear adaptive processor

Adaptive locally-optimum detection has been shown to suppress a broad range of radio interference types by tens of dB in direct-sequence spread-spectrum communications systems. One version, called NONAP, has been deployed as a software algorithm in US Navy low and very-low frequency (LF/VLF) strategic communication receivers. A high-speed version (HSNONAP) suitable for miniaturization has been developed in order to demonstrate the interference suppression capabilities of non-linear adaptive processing in higher data rate systems. Potential applications are Global Positioning System (GPS) receivers, ultra-high frequency, super-high frequency satellite and low probability of intercept communication systems. This paper describes the HSNONAP prototype. Results of low and high data rate testing (including operation with a CA-code GPS receiver) are presented