A Low-Power Dual-Frequency RF Front-End Architecture for GNSS Receivers

With the availability in the years to come of several new Global Navigation Satellite Systems transmitting signals located in different frequency bands, the question of the feasibility of multi-frequency receivers aimed at the mass market is of major interest. Most solutions proposed today either use single-frequency receivers in parallel or directly sample the signals at the antenna, two solutions which are not applicable to the mass market. In this paper, a dual-frequency RF front-end architecture with a similar power-consumption and complexity as current state-of-the-art single-frequency front-ends is proposed. It is based on a super-heterodyne architecture and exploits the fact that the L1C/A and L2C signals only occupy 2 MHz of the 20 MHz L1 and L2 bands to allow the simultaneous acquisition and tracking of both the L1C/A and L2C signals.