Academic Journal of Environment & Earth Science, 2024, 6(5); doi: 10.25236/AJEE.2024.060503.
Fusheng Wei1, Di Wu2
1Guangdong Environmental Protection Engineering Vocational College, Foshan, Guangdong, 528216, China
2Key Laboratory of Environment Change and Resources Use in Beibu Gulf, (Nanning Normal University), Ministry of Education, Nanning, Guangxi, 530001, China
BeiDou pseudolites are ground-based BeiDou-like signals transmitters to augment positioning accuracy and service availability of the BeiDou satellite navigation system. A significant challenge − the “near far problem” arises because sometimes the signals from the nearby BeiDou pseudolites are strong enough to block the satellite signals. One of the promising solutions is to pulse the pseudolite signals with a low duty cycle to reduce the interference. Some existing pulsing schemes, i.e., the RTCM SC-104 and the RTCA SC-159 have been proved effective in many applications. However, most of them are unable to provide a close, multiple pseudolite transmissions due to the random pulse pattern. In this paper, a pseudo-random pulse pattern based upon the theory of linear congruence has been proposed to improve the multi-access performance. The spectral and temporal characteristics of the proposed pulse pattern are analyzed and compared with the random pulse pattern. From the analysis, it emerges that the proposed scheme features better characteristics to facilitate multiple pseudolite transmission.
BeiDou pseudolite, pulsed signal, duty cycle, near-far problem, linear congruence
Fusheng Wei, Di Wu. Design of pulse pattern based on the theory of linear congruence for BeiDou pseudolite signals. Academic Journal of Environment & Earth Science (2024), Vol. 6, Issue 5: 12-22. https://doi.org/10.25236/AJEE.2024.060503.
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