Joint pilot tone and channel estimator design for OFDM systems

Optimal pilot design is an important issue for OFDM systems since the pilot tones significantly affect channel estimation performance. Unlike the conventional approaches which derive the optimal pilot tones along with a certain channel estimation method, this paper proposes a novel approach that optimizes the pilot tones and the channel estimator jointly based on the MMSE criterion. It can be shown that the proposed approach not only outperforms the conventional ones at low SNRs, but also reduces the complexity of the channel estimator at the receiver.