A Novel Acquisition Algorithm Based on a Composite Waveform for Weak CPM Signals

• Published in: IEEE communications letters Vol. 28; no. 5; pp. 1117 - 1121
• Main Authors: Xue, Rui, Xie, Mingming
• Format: Journal Article
• Language: English
• Published: New York IEEE 01-05-2024; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: Accumulation; acquisition; Algorithms; bit sign transition; Codes; coherent accumulation; Continuous phase modulation; Correlation; Fast Fourier transformations; Global navigation satellite system; Impact analysis; Modulation; Navigation; Phase modulation; Sensitivity; Symbols; Waveforms
• ISSN: 1089-7798; 1558-2558
• DOI: 10.1109/LCOMM.2024.3376994

Bit sign transitions cause significant attenuation of the correlation peak, thereby decreasing the acquisition probability. Based on an analysis of the impact of bit sign transitions on continuous phase modulation (CPM) acquisition, this letter proposes a fast parallel acquisition algorithm based on a composite waveform (FPACW) to overcome the effect of bit sign transitions. The algorithm combines the CPM waveforms corresponding to two different data bits to form a composite waveform as the new local replica waveform. Moreover, the accumulation correlation method and fast Fourier transform are utilized for correlation operations. Theoretical analysis and simulation results demonstrate that, compared to coherent, incoherent, and differential accumulation methods with the traditional CPM waveform acquisition, the proposed FPACW algorithm enhances acquisition performance by approximately 4 dB, 6 dB, and 7 dB, respectively, without increasing the computational complexity.