A five channel low cost GPS receiver

Abstract

A progress report on a program to develop a low-cost GPS (Global Positioning System) receiver for marine applications is presented. The unit described is a highly digital, mostly one bit, software intensive receiver. The unit uses one RF mixer to baseband, a one-bit 2-MHz A/D (analog-to-digital converter), and five digital parallel signal processing channels. An AMLE (approximate maximum likelihood estimator) technique is used to acquire signals, and low dynamic loops are used for tracking. General principles guiding the design and a description of the receiver are given.<>