Multipath Characterization and Mitigation Using Modernized Signals

Multipath causes the most errors in a well-designed navigational system. Despite many algorithms and techniques designed to reduce them, these errors still compromise most GPS receivers. The ideal solution to this problem would discriminate the paths and correct errors in real time, using hardware and software. In Phase I of this program, we have investigated different types of multipath and their effects on receiver performance. We’ve considered several possible solutions, and evaluated them under different circumstances. We have also considered the relationship between the complexity of multipath mitigation techniques and the complexity of receiver architecture. Based on these investigation we propose a novel receiver architecture comprising both spatial and multi-scale temporal domain capabilities. This approach promises robust detection, characterization and mitigation of diverse classes of multipaths. We propose to perform detailed engineering design, develop a working prototype and, finally, test and demonstrate its performance during Phase II. The development plan will follow our well-proven methodology and GPS development tools we have developed. The schemes include novel antenna development, block processing techniques and multiple mitigation filters.