Urban/Indoor Navigation Using Network Assisted GPS

摘要

GPS information is an essential element of network centric warfare providing key positioning and timing information in support of communication, positioning and navigation functions. For these networked GPS applications, it is also possible to improve the ability of GPS to operate in challenged environments, such as inside buildings, by using GPS Network Assistance. This paper describes the Network Assisted (NETASSIST) system architecture and a Software GPS Receiver (SGR) Test Bed that has been developed by NAVSYS Corporation under contract to CERDEC. The SGR is designed to use the positioning, timing and navigation data-aiding from a NETASSIST base station across a secure wireless network. This allows the receiver to apply advanced signal processing algorithms to speed direct P(Y) code acquisition and also allow the receiver to track GPS signals down to significantly lower C/N0 thresholds which enhances the receiver's ability to operate inside buildings. Test results collected using the NETASSIST SGR Test Bed are also presented in this paper to demonstrate the advantages of this approach for urban operations.