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arXiv · 2410.04653

Large-Scale GNSS Spreading Code Optimization

Alan Yang·Tara Mina·Stephen Boyd·Grace Gao
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Abstract

We propose a bit-flip descent method for optimizing binary spreading codes with large family sizes and long lengths, addressing the challenges of large-scale code design in GNSS and emerging PNT applications. The method iteratively flips code bits to improve the codes' auto- and cross-correlation properties. In our proposed method, bits are selected by sampling a small set of candidate bits and choosing the one that offers the best improvement in performance. The method leverages the fact that incremental impact of a bit flip on the auto- and cross-correlation may be efficiently computed without recalculating the entire function. We apply this method to two code design problems modeled after the GPS L1 C/A and Galileo E1 codes, demonstrating rapid convergence to low-correlation codes. The proposed approach offers a powerful tool for developing spreading codes that meet the demanding requirements of modern and future satellite navigation systems.

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Alan Yang, Tara Mina, Stephen Boyd, Grace Gao. 2024-10-06. Large-Scale GNSS Spreading Code Optimization. https://arxiv.org/abs/2410.04653

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