Globe navigation satellite system signal acquisition scanning system and acquisition method thereof

Abstract

The invention discloses a globe navigation satellite system signal acquisition scanning system and an acquisition method thereof, which belong to the technical field of signal processing. The method comprises the steps of: performing down-conversion on a GNSS signal which is received by a front end receiving data module to acquire a middle-frequency modulation signal and removing a carrier wave from the middle-frequency modulation signal to acquire a modulation sequence; performing fast Fourier transform on N points of the modulation sequence, acquiring a local coarse acquisition code chip according to an encrypted shift register and acquiring a frequency domain sequence of the local coarse acquisition code chip acquired by the fast Fourier transform of the N points; and circularly shifting the frequency domain sequence of the local coarse acquisition code chip by one bit right or left and multiplying the resulting frequency domain sequences of the local coarse acquisition code chip by a modulation frequency domain sequence respectively to acquire a frequency spectrum shift sequence, wherein the influence of the Doppler effect of one unit is changed each time the local coarse acquisition code chip frequency domain sequence is shifted by one bit. The chip frequency domain sequence acquired after the shift is multiplexed by the frequency domain of the received signal, and thus, all results of the influence of the different Doppler frequency domains on the received signal can be obtained.

Description

technical field [0001] The present invention relates to a method in the technical field of signal processing, in particular to a global satellite navigation system (GNSS) signal acquisition scanning system and acquisition method thereof. Background technique [0002] In the field of satellite navigation, it is necessary to capture the GNSS signal in space, but because the satellite signal itself is weak and susceptible to interference, it is difficult to capture. In addition, due to the high speed of satellite movement, the transmitted signal has a large Doppler frequency deviation. In order to be able to capture the correct signal, it is necessary to obtain the frequency of the received signal, so it is particularly important to obtain the Doppler frequency of the signal correctly, which is the premise of subsequent signal processing, otherwise the correct navigation message cannot be obtained. The frequency sweep during signal acquisition is to try the estimated Doppler f...

AI Technical Summary

Problems solved by technology

Without any optimization and improvement on the frequency sweep method, the memory space is too large and the time complexity of the calculation is also high

Images