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
dx.doi.org/10.1109/ACSSC.2008.5074471
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