Chunk-based Channel Estimation for Uplink OFDM

In this paper we address channel estimation for uplink OFDM over frequency-selective, time-varying channels. In the considered multi-user uplink, data flows of several users are assigned to time-frequency slots, termed chunks. In this case, only dedicated pilots located in chunks associated to a specific user can be used for channel estimation. We investigate pilot-aided and iterative channel estimation techniques based on Wiener filtering and study the impact of the chunk size on the channel estimation performance. We show by means of numerical simulations that iterative approaches are particularly beneficial for channel estimation using dedicated pilots per chunk