Cyclic spectral analysis of OFDM/OQAM signals

The orthogonal frequency division multiplexing signals based on the offset quadrature amplitude modulation (OFDM/OQAM) with pulse shaping are cyclostationary. Utilization of the cyclostationarity provides significant advantages in detection, identification, synchronization, and parameter estimation of these signals. In this paper, a matrix-based, stochastic method for the cyclic spectral analysis of OFDM/OQAM signals with pulse shaping, based on their aperiodic homogenous Markov chain representation, is proposed. Explicit expressions for the nonconjugate and conjugate cyclic spectrum of the complex envelope of these signals are derived by applying the proposed method. Cyclostationary characterizations of the nonconjugate and conjugate cyclic features at the cycle frequencies associated with the symbol rate and with the double carrier frequency, respectively, are performed. The final expression for the cyclic spectrum of the pulse shaping OFDM/OQAM signals is also derived. Some simulation results for the cyclic spectral analysis of these signals, based on the fast Fourier transform accumulation method (FAM), which confirm the theoretical results, are presented, as well.