An Unambiguous Acquisition Algorithm for TC-OFDM Signals Based on BOC Modulation

The utilization of binary offset carrier (BOC)-modulated signal in communication and navigation fusion system is promising, which can share the communication and navigation frequency band as well as improve the positioning accuracy. In this paper, BOC modulation is introduced into the time and code division orthogonal frequency division multiplexing (TC-OFDM) system, leading to multiple peaks of autocorrelation function (ACF), which will absolutely result in acquisition ambiguity in the traditional BPSK signal receiver. An unambiguous acquisition method based on reconstruction of side peak suppression (RSPS) is proposed. By constraining the non-linear combination of local waveform and received signal without side peak, the local waveform unambiguous waveform set is obtained, and the autocorrelation function is reconstructed. Theoretical analysis and simulation results show that under a good condition of SNR, the unambiguous acquisition algorithm RSPS proposed in this paper can compress the correlation peak width of the BOC (14, 2) modulated communication and navigation fusion signal by more than 80% under the same detection probability as the traditional acquisition method.