In this paper, we aim to provide an analytical modeling of cyclic delay diversity in an OFDMA based system. Cyclic delay diversity is a low complexity spatial diversity scheme where multiple transmit antennas transmit delayed versions the same signal. While CDD increases the frequency selectivity, the reduced coherence bandwidth resulted in higher requirements for the channel estimation at the receiver. This paper presents a preliminary model with objective of providing tradeoff study of maximum tolerable cyclic delay value vs. performance impacts to the system.