Combining to devise radio telemetry receiver, the application of digital down converter and frequencydemodulation in software radio is discussed and analysed.
Two kinds of signal processing methods for heterodyne interferometer, phase locked frequencydemodulation and combinatorial frequencydemodulation are presented in this paper.
介绍了两种激光外差干涉信号的处理方法锁相频率解调法及组合频率解调法。
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The phase- locked loop is one kind of control system which is able to achieve phase automatic lock, to compose frequency and to trace demodulation system.