Analysis of Subcarrier-Assisted Acquisition Methods for Galileo E5 AltBOC(15,10)

Galileo E5 AltBOC(15,10) stands at the forefront of modern signal modulation schema, albeit accompanied by processing challenges. This signaling method utilizes a complex subcarrier to spread the signal into two distinct frequency lobes, both containing separate multiplexed data and pilot channels. E5-AltBOC modulation improves tracking performance by sharpening the peak of the Auto-Correlation Function (ACF) at the expense of introducing signal processing ambiguity. Additionally, E5-AltBOC has a unique signal structure with an evolving interpretation of its subcarrier. In this paper, four acquisition methods are compared by means of probability of detection in the presence of thermal noise and ionospheric effects using extensive Monte Carlo analysis of simulated of E5-AltBOC waveforms. A set of front end configurations are implemented to examine the effects of band limited processing of E5-AltBOC. This examination provides a nuanced understanding of current AltBOC acquisition algorithms and provides actionable insights for researchers that desire to develop novel receiver architectures for Galileo E5 AltBOC(15,10).