基于FPGA的多模式通信信号解调及自适应位同步技术

通信信号的识别与解调是通信侦察的重要组成部分。本文在假设侦察识别过程已经完成,且调制模式主要为FM、FSK、BPSK和QPSK四种方式,码速率在一定范围内变化的前提条件下,讨论这四种不同模式通信信号的解调技术,在解调中引入自适应的位同步技术,保证解调结果的正确输出。整个系统各模块基于FPGA实现,便于编程、修改以及升级改进,利于移植。

The Demodulation of Multi-mode Communication Signals and the Adaptive Symbol Synchronization Technique Based on FPGA

The identification and demodulation of the communication signals are important parts in communication surveillance. Supposed that the identification process was finished, and the modulation modes were Frequency Modulation(FM), Frequency Shift Keying ( FSK), Binary Phase Shift Keying(BPSK) as well as Quadri Phase Shift Keying (QPSK), at the same time, the symbol-rate was varied in a certain range, the demodulation techniques about the four modes of the communication signals are discussed in this paper. The adaptive symbol synchronization technique is imported in the demodulation to ensure the output is right. The realization of the whole system is based on a single FPGA(Field Programmable Gate Array). Each module is easy to be programmed, modified and transferred.