Analysis of a novel low complex SNR estimation technique for OFDM systems

Signal-to-noise ratio (SNR) estimation is commonly used in wireless receivers to enhance the performance in different ways. In this paper a novel low complexity SNR estimator for OFDM is proposed. The estimator might be implemented using floating point representation or by using only the sign-bit, and can if desired be effectively implemented by reconfiguring the standard correlator used for time- and frequency estimation. Closed form expressions for the SNR estimate are derived for both the floating point implementation and the sign-bit implementation, and compared to simulation results both for an additive white Gaussian noise (AWGN) channel and for a frequency selective channel showing the feasibility of the proposed algorithm.