Unambiguous Acquisition/Tracking Technique Based on Sub-Correlation Functions for GNSS Sine-BOC Signals

Area of Science:

• Satellite Navigation Systems
• Signal Processing
• Telecommunications Engineering

Background:

• Global Navigation Satellite System (GNSS) signals, particularly Binary Offset Carrier (BOC) modulated signals, suffer from autocorrelation function (ACF) ambiguities.
• Existing ambiguity removal methods for BOC signals are inadequate for high-order signals or compromise narrow correlation properties.

Purpose of the Study:

• To propose a novel sub-function reconstruction synchronization algorithm (SRSA) for unambiguous GNSS signal acquisition and tracking.
• To address the limitations of current methods in handling high-order BOC signals and maintaining signal characteristics.

Main Methods:

• Design of a new local auxiliary code by segmenting the local Pseudo-Random Noise (PRN) code into delayed sub-codes.
• Coherent integration of the auxiliary code with the received signal.
• Multiplication of correlation results to generate an unambiguous correlation function, eliminating positive side peaks.

Main Results:

• The proposed SRSA achieves superior detection probability (0.5 dB-Hz better than ASPeCT) for signal acquisition.
• SRSA demonstrates superior performance in phase-detection curves, anti-multipath, and anti-noise capabilities for tracking.
• For high-order BOC signals, SRSA effectively eliminates false lock points and reduces multipath error envelopes.

Conclusions:

• The SRSA offers a robust solution for unambiguous GNSS signal synchronization, particularly for complex BOC signals.
• The algorithm provides significant improvements in acquisition and tracking performance compared to BPSK-LIKE, SCPC, and ASPeCT methods.
• SRSA maintains code tracking error comparable to ASPeCT while enhancing overall signal robustness.