GMSK SIGNAL DEMODULATION METHOD AND ITS DEVICE

摘要

PURPOSE: To demodulate a GMSK signal accurately by compensating an offset error by digital arithmetic processing without decoding a clock pulse superimposed on a transmitted GMSK signal. ;CONSTITUTION: A band pass filter 10, 1st and 2nd mixers 20, 21, a local oscillator 30, and a phase delay device 40 are used to transit a received GMSK modulation signal to a base band, to separate the signal into I and Q component reception signals and 1st and 2nd low pass filters 50, 51 and 1st and 2nd replacement devices are used to quantize and binary-code the signals. An offset error detection section 92 detects a slot period and an offset error amount, and a phase synchronization section 93 compares the error with reference waveform data stored in a memory 91 to compensate the data. A software decision section 94 and a GMSK demodulation data detection section 95 integrate the compensated data and decide I component, Q component demodulation data based on the result of integration to conduct GMSK demodulation.;COPYRIGHT: (C)1994,JPO