SNR Estimation in OFDMA/TDD Based WiBro System

This paper presents the signal-to-noise ratio (SNR) estimations for OFDM based system. In this paper, we examine simple SNR estimators, DASS (difference of adjacent subcarrier signal) estimator and EVM (error vector magnitude) estimator, which can be easily implemented into hardware. Moreover, we examine the effect factors which degrade the performance of SNR estimation in practical environment. The effect factors might be timing offset and frequency offset of received signal, and overlapping window length of transmitter. These factors have an impact upon SNR estimation at high SNR region. Thus, we propose the differential-DASS to improve the estimation performance according to the change of time and frequency offset at high SNR region.