Channel equalisation for OFDM using scattered pilots

Introduction Channel equalisation for OFDM signals is an important aspect for achieving good communication performance. Several OFDM based standards, like the European standard DVB-T and the Japanese standard ISDB-T, have adopted the approach of inserting scattered pilots in each transmitted OFDM symbols for some of the modulation modes. Since the data modulated on these scattered pilots are prior knowledge, it is possible for a receiver to calculate the channel response at these pilot sub-carriers positions. The resulting sub-sampled channel response information can then be used to make an estimate of the channel response for equalisation purposes. Many authors have discussed the use of scattered pilots for channel estimation and equalisations in the literature, see [1], [2], [3] and [4].