ESTIMATION OF SIGNAL-TO-NOISE RATIO BY PROCESSING MEASURED ERROR VECTOR MAGNITUDE

摘要

The signal-to-noise ratio of a demodulated received signal is estimated by measuring the error vector magnitude (EVM) of the demodulated signal; and processing the measured EVM in combination with a correction term to estimate the signal-to-noise ratio of the demodulated signal. The correction term is a polynomial function of the measured EVM. The signal-to-noise ratio is estimated in accordance with the formula: (I) wherein µZ is the measured EVM based on the mean of a Rayleigh density of EVM measurements; and C is the correction term. For QPSK modulated signals, C is calculated in accordance with the formula: (II) For BPSK modulated signals, C is calculated in accordance with the formula: (III).