GNSS long code signal capturing method and device assisted by low earth orbit satellite

Abstract

The invention provides a GNSS long code signal capturing method and device assisted by a low earth orbit satellite. The GNSS long code signal capturing method assisted by the low earth orbit satellitecomprises the following steps: acquiring GNSS baseband signals; performing frequency mixing operation; performing segment correlation operation; performing long-time coherent integration; carrying out incoherent integral operation; and performing peak detection and threshold judgment. The method and the device have the advantages that GNSS navigation signal auxiliary information, including roughDoppler information and rough code phase information, is acquired under the assistance of a low-orbit satellite, so that on one hand, the rough code phase information is used for generating sub-codesof local ranging codes and participating in related operation; it is guaranteed that the influence of bit hopping on coherent integration time is eliminated after correlation operation, high-sensitivity capturing of long codes is achieved through long-time coherent integration, and the long code signal capturing performance in the low signal-to-noise ratio environment is improved; and on the otherhand, rough Doppler information and rough code phase information of the GNSS navigation signals are utilized, the searching time of the signals in the frequency dimension and the code dimension is shortened, the capturing efficiency is improved, and rapid capturing of GNSS long code signals is achieved.

Description

technical field [0001] The invention relates to the field of navigation, in particular to but not limited to a low-orbit satellite-assisted GNSS long-code signal acquisition method and device. Background technique [0002] The Global Satellite Navigation System (GNSS) is a comprehensive constellation system including the global navigation systems of the United States, Russia, Europe and China, as well as the regional navigation systems of Japan, India and other countries. On the one hand, with the gradual establishment of each system, the signal structure of the GNSS system becomes more and more complex, which poses new challenges to the design of the signal system and the development of the navigation receiver. In order to enhance the performance of the satellite navigation system signal, the United States first proposed the GPS modernization plan, one of which is to issue a new long-period code signal, that is, the M code signal. This new long code signal utilizes the BOC...

AI Technical Summary

Problems solved by technology

In GNSS system application environments such as urban canyons, forests, mountains and electromagnetic interference, it is difficult for ordinary receivers to meet the acquisition requirements of weak signals in these complex environments

Images