Comparison of Narrowband Adaptive Filter Technologies for GPS

Narrowband interference can seriously degrade the performance of GPS systems. Several techniques exist for reducing this interference, including adaptive transversal filters, overlapped FFTs, and filter banks. All these techniques attempt to filter out the interference before the GPS receiver performs correlation. This paper compares these three interference suppression techniques for application to GPS. Likely VLSI-based designs with various levels of complexity (i.e., operation counts) for each technique are proposed and described. The effects of these designs as pre-processors on GPS ranging performance is then compared using computer simulation.