数字AGC与捕获联合实现的直接序列扩频解调结构

摘要

本文针对直接序列扩频（Direct Sequence Spread Spectrum，DSSS）系统中自动增益控制（Automatic Gain Control，AGC）及捕获这两个基带信号处理必不可少的模块，提出一种数字AGC与捕获联合实现的解调结构。该联合解调结构能够利用数字AGC模块产生的增益控制系数同时调整接收信号的幅度以及捕获模块的判决门限。相较于固定门限判决算法，该结构在不增加实现复杂度的前提下，虚警概率性能提高不小于5dB，单次捕获概率性能提高0.6dB。%A demodulation structure of digital AGC and capture joint realization is proposed in this paper. The gain control coefficient generated from AGC module is used for adjusting the amplitude and the decision threshold simultaneously. Compared to the fixed threshold decision algorithm, the probability of false alarm performance is increased no less than 5dB, and the probability of a single capture performance is improved 0.6dB in the structure, without increasing implementation complexity.