Maximum likelihood based methods for OFDM intercarrier spacing characterization

One of the main task to be done by a cognitive receiver is to sensing its spectral environment in order to distinguish surrounding systems from each others. Actually most systems (such as WiMAX, WiFi, DVBT) are based on OFDM modulations but differ from their intercarrier spacing used in OFDM modulation. Therefore carrying out accurate intercarrier spacing estimator is a crucial step in cognitive radio. In this paper, we propose a new efficient algorithm to estimate the intercarrier spacing based on maximum-likelihood principle. Its performance is analysed through numerical simulations and compared to standard existing approaches.