Title: Blind FrFT-OFDM signal parameters estimation for underlay cognitive radio based on second-order cyclo-stationarity feature
Authors: Ehab M. Shaheen
Addresses: Electronic Warfare Department, Military Technical College, Cairo, Egypt
Abstract: Fractional Fourier transform (FrFT) OFDM scheme has been proposed previously in order to alleviate the problem of high peak to average power ratio (PAPR) of OFDM and its immunity against inter carrier interference. The cyclo-stationarity property of FrFT-OFDM is often neglected in the literature. In this paper, this missing analysis is provided and a blind algorithm for FrFT-OFDM signal parameters estimation is proposed. Novel mathematical formulas for the autocorrelation function of the FrFT-OFDM signal over both AWGN and fading channels are derived. These mathematical formulas show that the FrFT-OFDM signal has a cyclo-stationarity property. Also, novel mathematical formulas are derived for cyclic autocorrelation function of the FrFT-OFDM signal over both AWGN and fading channel models. Simulation results for the cyclic autocorrelation function show that signal detection and parameters estimation based on FrFT-OFDM cyclo-stationarity are feasible. The case of underlay cognitive radio is also investigated.
Keywords: fractional Fourier transform OFDM; cyclo-stationarity; fading channel model.
International Journal of Vehicle Information and Communication Systems, 2017 Vol.3 No.3, pp.230 - 247
Received: 17 Jul 2016
Accepted: 14 Mar 2017
Published online: 21 Oct 2017 *