一种示位标信号的数字化解调方法

卫星紧急无线电示位标(简称示位标)是一种在紧急情况下向国际搜救组织卫星发射求救信号的装置.示位标发射的是一种调相信号,传统的在检测时用的示位标检测仪通常利用模拟方法对信号进行解调.采用模拟解调方法虽然原理简单但电路实现比较复杂,且对生产调试要求较高,若电路设计不合理还非常容易受到温度、电磁干扰的影响.随着近年数字器件处理能力的提高,越来越多的信号解调由数字化方式实现.本文提出的针对示位标信号的数字化相位解调方法可以采用单片机和FPGA实现,采用数字化方法进行解调具有体积小、调试简单等诸多优点.

Digital demodulation method for emergency position indicating radio beacon

Emergency position indicating radio beacon(EPIRB)is a kind of device which can send rescue signal to COSPAS-SARSAT satellites. The signal send by beacon is a kind of phase modulated, analog method is usually used to demodulate the beacon signal. It is simple to use analog method in theory, but difficult to realize. The analog circuit is affected easily by temperature、electromagnetism and hard to prduce. More and more signals are demodulated by digital method because of the DSP technology. Beacon signal can also be demodulated by FPGA and CPU, using digital method can reduce product's size and simplify producing process.