Precise estimation of noise power and SNR from OFDM signals

This paper describes the signal to noise ratio (SNR) estimation method for OFDM system. While many prior researches on SNR estimation uses training sequence's subcarriers to measure noise power, our proposed method measures noise power from unused subcarriers of training sequences since most of OFDM systems leave some subcarriers in training sequences unused for various purposes. This method proved simple and accurate compared to other conventional methods and showed satisfactory accuracy even when only a few unused subcarriers are available.