Development, implementation and validation of a real-time Galileo E1-B signal acquisition and tracking scheme

With the introduction of a square wave sub-carrier modulation in the Galileo E1 BOC(1,1) open service signal, the autocorrelation function becomes more complex as compared to the GPS L1 C/A BPSK(1) signal. Indeed, the presence of two secondary side lobes introduces an ambiguity increasing the risk of false peak detection and causing a higher complexity in the acquisition phase. Consequently, for ensuring reliable processing, new strategies must be developed to acquire and track satellites signals. Existing or already proposed BOC(1,1) algorithms and their limitations are first reported. Based on this foreground, this paper details the development, the implementation and the real-time validation of a complete acquisition and tracking scheme as part of a full Galileo E1 receiver prototype developed at IMT [1]. Possible algorithms and architecture improvements are also discussed. Finally, an important effort is dedicated to the algorithms and prototype validation with a Spirent GSS 7800 12 channels Galileo E1 simulator. This paper is thus significant in that it not only reports on the study and implementation of possible algorithms for the new Galileo E1 BOC(1,1) open service signal, but also reports on their real-time validation.