Implementation of GPS Software Receiver Based on GNU Radio

It's difficult for traditional hardware GPS receivers to expand from single-band to multi-band and from single-constellation to multi-constellation. In this work, the idea of software defined radio is applied and the technical solution of the GPS signal processing based on the open source software radio frame GNU Radio is proposed. GPS signal acquisition, tracking, navigation message demodulation and positioning are realized with C++, multi-channel parallel processing is achieved exploiting the scheduler module provided by GNU Radio, and it's shown that the design is able to run real time GPS signal processing. The software prototype meets the requirements of flexibility and reusability, and the positioning accuracy is proved to be comparable with the commercial hardware receiver. This work benefits the research and design of multi-band multi-constellation GNSS receivers.