Development of a New Generation Spaceborne GPS Receiver

We are investigating a new generation spaceborne GPS receiver that can determine a position more precisely, but which is smaller, with lower cost and lower power consumption than a conventional receiver. This new type of spaceborne receiver includes a CMOS silicon on insulator (SOI) chip and adopts a direct sampling approach to process GPS signals. Moreover, this receiver can receive not only legacy GPS signals (L1) but also new civil codes on L2 and L5 frequency bands, for which it has 16 channels each and more than 64 channels in all. Furthermore, this receiver has 6 RF inputs; it can be configured for various applications. In this paper, the concept of the new GPS receiver is explained and the preliminary design results of a receiver signal-processing module are presented. Moreover, we experimentally produced a signal-processing module and evaluated measurement errors of the pseudo-range and carrier phase on each signal. Consequently the validity of this receiver to adopt the direct sampling approach was confirmed. Those results are also described in detail.