Potential candidates for new SBAS signals

Abstract : Satellite-Based Augmentation Systems (SBAS) provide single-frequency services for aeronautical users by broadcasting corrections and integrity information on L1 frequency. Future dual-frequency services for aeronautical users will be broadcast on L5-I/E5a-I frequency. New services that could be potentially provided by SBAS to non-aeronautical community are currently being investigated. These services may require higher data rates that challenge current SBAS signal definitions. Considering there is, at this time, no standardized SBAS signal neither on L5/E5a-Q component nor on E5b frequency band, an opportunity to evaluate new signal candidates is identified. In this paper, several candidates are proposed and compared with a baseline candidate. The baseline candidate is the current signal structure of SBAS signals, L1-I and L5-I/E5a-I. The comparison is made in terms of data rate, latency, data demodulation performance and receiver complexity as number of real additions and multiplications. It is observed that it is possible to increase the data rate and to reduce the latency without degrading the data demodulation threshold and with a reasonable complexity increase. Moreover, a compatibility analysis has been conducted which shows an impact smaller than 0.1dB of C/No degradation in any signal processing operation of any L5/E5a frequency band signal.