Channel equalisation for OFDM using scattered pilots

Channel impairments, such as multipath reflections, can have a profound impact on the bit error rate achievable in OFDM transmission applications. This paper presents a new channel equalisation technique that uses scattered pilots in OFDM symbols to estimate the delay parameters associated with a two-path model as an approximation of a multipath channel. It is applicable for both fixed and mobile reception. Results from simulation studies under multipath Rayleigh channel have shown that the algorithm can offer a substantial performance improvement over that obtained with a conventional linear interpolation approach, used as a benchmark. This is also confirmed by applying the algorithm to data recorded by an OFDM receiver in practical experiments that involved reception of five transmissions of OFDM symbols both ´off air´ and through a channel simulator.