Satellite signal acquisition method and apparatus

Abstract

The invention discloses a satellite signal acquisition method and a satellite signal acquisition apparatus applying the related method. According to the satellite signal acquisition method and the apparatus, the calculation amount in a satellite signal acquisition process is effectively reduced, and the acquisition sensitivity is improved. The satellite signal acquisition method specifically comprises the following steps: generating a local carrier; down-converting an input satellite signal; generating a pilot channel and a data channel spreading code, respectively; completing pilot channel signal and data channel signal acquisition; inverting a sign of an imaginary part of pilot channel acquisition data; exchanging real and imaginary parts; obtaining a data channel acquisition result copy; accumulating the data channel acquisition result copy and the data channel acquisition result; subtracting the data channel acquisition result copy and the data channel acquisition result; and selecting a maximum value to perform acquisition judgment.

Description

technical field [0001] The invention relates to the technical field of satellite navigation, in particular to a satellite signal acquisition technology. Background technique [0002] With the rapid development of satellite navigation systems, B2A is the second civilian signal of Beidou-3, which is used to replace the B2I signal of Beidou-2. It mainly provides services for dual-frequency or triple-frequency receivers, and can be used for life safety services and high-speed High-performance services such as precision measurement can also be used for consumer services with higher performance requirements. [0003] The subcode of the Beidou III generation B2A signal is 1 millisecond, that is, there may be different subcode modulation symbols between each millisecond, which means that the coherent integration length during acquisition cannot exceed 1 millisecond, and its acquisition gain is limited, so that the acquisition sensitivity lower. In order to improve the capture sens...

AI Technical Summary

Problems solved by technology

[0003] The subcode of the Beidou III generation B2A signal is 1 millisecond, that is, there may be different subcode modulation symbols between each millisecond, which means that the coherent integration length during acquisition cannot exceed 1 millisecond, and its acquisition gain is limited, so that the acquisition sensitivity lower

In order to improve the capture sensitivity, the usual way is to do incoherent capture, but incoherent capture will bring square loss

If you want to further improve the capture sensitivity, you need to perform a long time of non-coherent integration, which will increase the amount of capture calculations to a certain extent

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