Coherent multi-carrier acquisition method and device

Abstract

The embodiment of the invention provides a coherent multi-carrier capturing method and device, and the method comprises the steps: generating a Doppler factor / code phase two-dimensional plane of a subcarrier for a received signal of a subcarrier signal, searching a code phase maximum value on the two-dimensional plane, and the code phase maximum value serving as a code phase estimation value; calculating a carrier phase compensation amount of the subcarriers according to the code phase estimation value, obtaining a receiving signal subjected to carrier phase compensation by combining a two-dimensional plane, and carrying out coherent combination on the receiving signals subjected to carrier phase compensation of all subcarriers; and comparing the merged received signal with a preset monitoring threshold to obtain a correlation peak exceeding the monitoring threshold, and respectively obtaining the frequency offset value and the propagation delay of the subcarrier according to the Doppler factor and the code phase of the correlation peak on the two-dimensional plane of the subcarrier. According to the embodiment of the invention, the defects of a non-coherent capturing method in a high-dynamic, large-frequency-point coverage range and weak-signal environment are overcome, the capturing performance is greatly improved, and the average capturing time is shortened.

Description

technical field [0001] The present invention relates to the technical field of multi-carrier direct sequence spread spectrum communication, and more specifically, relates to a coherent multi-carrier acquisition method. Background technique [0002] MC-DS-CDMA technology is an organic combination of single-carrier direct-sequence spread spectrum code division multiple access technology (SC-DS-CDMA) and multi-carrier (MC) technology. The advantages of intercept probability and other aspects, and the excellent characteristics of multi-carrier technology in spectrum utilization, anti-frequency selective fading and strong interference avoidance, can effectively deal with the above-mentioned challenges faced by the low-orbit satellite communication constellation system, and can be applied to low-orbit satellite in orbit (LEO) satellite communication system. [0003] The LEO system has the characteristics of low signal-to-noise ratio, high dynamics, and low delay. However, as a 4G...

AI Technical Summary

Problems solved by technology

This algorithm improves the false alarm performance of MC-DS-CDMA signal in the environment of low SNR by incoherently combining the energy and spreading gain scattered on each subcarrier, but the incoherent combining method cannot Avoiding the introduction of signal-to-noise ratio loss, and with the increase of the number of subcarriers participating in the combination, the loss also increases, so that the spreading gain scattered on each subcarrier cannot be fully utilized, deteriorating the MC-DS- The acquisition performance of the CDMA receiver; in addition, the algorithm also has the problem that the peak position of the correlation result is not uniform and cannot be directly combined because the Doppler is large, so it is not suitable for the actual low-orbit satellite communication constellation system

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