Using bisection method for fast CFO estimation in OFDM systems

The number of mobile subscribers has increased tremendously in recent years. The orthogonal frequency- division multiplexing (OFDM) system carries the message data on orthogonal subcarriers for parallel transmission, combating the distortion caused by the frequency selective channel or equivalently, the inter-symbol-interference in the multi-path fading channel. Carrier frequency offset (CFO) in OFDM systems, which can induce the loss of orthogonality among subcarriers and result in significant performance degradation, is critical to be estimated and compensated for. In this paper, the pilot symbol is used to estimation CFO in OFDM systems. We use a Bisection method to obtain estimation performance of CFO well and fast.