COMMUNICATION QUALITY ESTIMATION METHOD, COMMUNICATION QUALITY ESTIMATION APPARATUS, AND COMMUNICATION SYSTEM

摘要

An average signal point amplitude detection section 15A determines an average position of I and Q components when a received QPSK modulated signal is demodulated and a threshold calculation section 15B determines threshold ths on an IQ plane based on the average signal point position of the received QPSK modulated signal and a theoretical distribution position on the IQ plane of signal points of a 16-value QAM signal. Then, a threshold decision section 14A makes a threshold-decision on the I and Q components of sequentially received QPSK modulated signals using this threshold ths and thereby calculates a simulated bit error rate of the 16-value QAM signal.