A study on interference detection scheme using AIC for UWB MB-OFDM systems

Abstract

Ultra-Wide Band (UWB) spectrum causes interference to primary wireless communication systems whose spectra overlap the UWB band because UWB systems make use of huge bandwidth compared with the primary systems. Therefore, we have to implement Detect-And-Avoid (DAA) techniques to detect the primary system and control the signal transmitted from the UWB devices. Although there is the energy detection scheme for detecting the primary signal based on a threshold, it is difficult to find an appropriate threshold. In this paper, we investigate a novel detection scheme for UWB Multi-Band OFDM system. The proposed method detects the presence of the primary system using estimates of the primary signal and the noise variance based on the maximum likelihood criterion. Moreover, we introduce Akaike Information Criterion (AIC) in order to select the most suitable primary signal model out of some possible models. As a result, the proposed method dynamically find the threshold to detect the presence of the primary signal in sharp contrast to the conventional energy detection method which uses a static threshold. By the computer simulations, we show that the proposed method outperforms the conventional method with respect to missed-detection and false-detection probabilities.