METHOD FOR APPLYING VARIABLY DIGITAL MODULATION/DEMODULATION METHOD IN MOBILE COMMUNICATION SYSTEM

摘要

PURPOSE: A method for applying variably a digital modulation/demodulation method in a mobile communication system is provided to switch the digital modulation/demodulation method to a 16QAM method according to a measured result by measuring an S/N(Signal to Noise) ratio of a received signal. CONSTITUTION: A call service is connected in mobile communication(S11). A data transmission and reception process is performed between terminals and an S/N ratio of a signal received from the terminal is measured(S13). A state of a radio channel is checked by comparing the measured value of the S/N ratio with a reference value stored in the terminal(S15,S17). An existing QPSK digital modulation/demodulation method is maintained if the radio channel is in the normal state(S19). The existing QPSK digital modulation/demodulation method is switched to 16QAM if the radio channel is in the abnormal state(S21).