Global Positioning System (GPS) User Equipment (UE) Time Aiding Using WWV/WWVB

Time to first fix (TTFF), i.e., the initial acquisition of GPS signals can be quite large when the GPS UE has a degraded timing solution or during a cold-start, when the UE has absolutely no knowledge of time or initial position. In addition, the Coarse Acquisition (C/A) code may not always be available due to interference. In these cases direct acquisition of GPS Precision Code or P(Y) and GPS Military code or M-code may not be possible without providing the GPS UE with accurate timing information from other sources. In this proposal GIRD Systems proposes to use RF timing signals such as the WWV low-frequency radio stations broadcast by the National Institute of Standards and Technology (NIST) to provide relatively accurate timing signals to GPS UE as time aid during C/A degradation and/or during a cold start. Hardware prototype design consideration will also be given during Phase I for subsequent Phase II implementation. BENEFIT: This SBIR program aims to develop into a potential product that supplies military GPS receivers with external time aid information for C/A stressed application or for a cold start with only P(Y) code signals. Such additional information may also be used for civilian GPS services to speed up TTFF.