Multi-Platform Signal Processing and Trajectory Estimation for Navigation in Difficult GPS Environments

A common feature of existing methods for improving the GPS performance is the attempt to enhance signal processing and navigation estimation parts of a single receiver. At the same time, potential that is inherent to the integration of data from multiple receivers remains completely underutilized. To utilize this potential, we propose to develop a MUlti-platform Signal and Trajectory Estimation Receiver (MUSTER) technology that will integrate signals and measurements from multiple GPS receivers organized into a collaborative network. The technology will enable: 1) Integration at the signal processing level, including: 1.1) Multi-platform accumulation of weak signals; 1.2) Multi-platform phased arrays for jamming suppression; and, 2) Integration at the measurement level, including: 2.1) Joint estimation of the receiver navigation states; 2.2) Multi-platform integrity monitoring. Development of the MUSTER technology will be built on an open-loop GPS receiver methodology that has been previously explored for stand-alone GPS receivers. Phase I will investigate into algorithms and methods of multi-platform GPS processing; will demonstrate their feasibility in simulated environments; and, will perform limited demonstration with experimental data. The MUSTER technology will be developed to meet limitations of military communication networks, to support processing of unsynchronized data and to maintain robust performance under data latencies. BENEFIT: Phase I effort will demonstrate that signals and measurements can be combined from multiple non-synchronized and non-collocated GPS receiver to a) increase the signal-to-noise ratio; b) enhance beam-forming capabilities for interference mitigation; and c) improve the overall satellite availability for solution estimation and integrity monitoring. Phase I will also analyze real-time implementation aspects of a combined FPGA/software implementation of the multi-receiver technology as well as its functionality within military communication networks where data rate limitations serve as the main challenge. As a result, Phase I will determine the system architecture that optimizes the benefits of multi-platform integration under the limitations of computational power and data exchange capacity. These anticipated results will lay the foundation for Phase II prototyping and technology demonstration.