DSP IMPLEMENTATION OF (10, 1) BINARY OFFSET CARRIER MODULATION FOR IRNSS APPLICATION

Binary Offset Carrier-modulated signals are widely used in current and nextgeneration global navigation satellite systems (GNSSs). IRNSS (NavIC), Indian regional navigational satellite systems uses composite signal in which one BPSK signal with two sine BOC (5, 2) modulated signals are combined. The main idea behind using BOC modulation is to reduce the interference with BPSK modulated signal, which has a sinc shaped spectrum and have most of their spectral energy concentrated around the carrier frequency. BOC-modulated signals have low energy around the carrier frequency and spectral lobes further away from the carrier. It also helps in resisting multipath effects and other types of noise in the channel. This paper presents generation of (10, 1) BOC signal which provides wide spectral separation for IRNSS application, and analyses its spectral characteristics. The simulated system is implemented on TMS DMDSP6437 which is a high end video processing DSP kit.