OFDM spectral characterization: estimation of the bandwidth and the number of sub-carriers

This paper deals with the analysis of modulated signals in a NDA (non data aided) context. Assuming the detection of an OFDM signal, our goal is to estimate the bandwidth and the number of sub-carriers of this signal. First, we propose an algorithm based on wavelet decomposition in order to estimate the bandwidth: bandwidth is correctly estimated in 100% of the cases with an error lower than 8% until the SNR = 3 dB. Second, we apply the MUSIC algorithm with decision criterion to obtain the number of sub-carriers: the number of carriers can be estimated with an error lower or equal to 9% in 100% of the cases until the SNR = 10 dB.