A Fast Positioning Method Without Navigation Data Decoding for Assisted GPS Receivers

Abstract

This paper describes an assisted positioning approach for Global Positioning System (GPS) receivers without navigation data extraction from the received signals. In the presented approach, pseudorange values are reconstructed from partially available measurements, as opposed to conventional techniques, and five or more satellites are used for position computation. The technique is based on iterative estimations of satellite times of transmissions, receiver time, and position using a least-squares method. It is computationally similar to conventional GPS positioning algorithms, but the time to first fix is reduced as there is no need to recover the time of week from navigation data.