Previous studies on the cyclostationarity aspect of orthogonal frequency division multiplexing (OFDM) signals considered only second-order cyclostationarity or assumed additive white Gaussian noise (AWGN) channel for propagation. This paper presents new results for the nth-order cyclostationarity of OFDM signals transmitted through time dispersive channels. An analytical closed-form expression is derived for the nth-order cyclic cumulant polyspectum of OFDM signals propagating through such channels, and affected by additive Gaussian noise, carrier phase, and frequency and symbol timing offsets at the receiver end. Furthermore, a necessary and sufficient condition on the oversampling factor per subcarrier is derived for such signals to avoid aliasing. Numerical results are presented.

Cyclostationarity, OFDM, Time dispersive channel
2008 42nd Asilomar Conference on Signals, Systems and Computers, ASILOMAR 2008
Department of Systems and Computer Engineering

Punchihewa, A. (A.), Dobre, O.A. (O. A.), Zhang, Q. (Q.), Rajan, S, & Inkol, R. (R.). (2008). The nth-order cyclostationarity of ofdm signals in time dispersive channels. In Conference Record - Asilomar Conference on Signals, Systems and Computers (pp. 574–580). doi:10.1109/ACSSC.2008.5074471