On Optimum Pilot Design for Comb-Type OFDM Transmission over Doubly-Selective Channels

IEEE Transactions on Communications (Impact Factor: 1.99). 04/2011; 59(4):930-935. DOI: 10.1109/TCOMM.2011.020411.100151
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We consider comb-type OFDM transmission over doubly-selective channels. Given a fixed number and total power of the pilot subcarriers, we show that the MMSE-optimum pilot design consists of identical equally-spaced clusters where each cluster is zero-correlation-zone sequence.

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Available from: N. Al-Dhahir, Jul 15, 2015
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    • "For channel estimation in OFDM, P equally spaced pilot signals are inserted at the transmitter [23] [24] [25]. Based on this known pilot sequence, the receiver finds the MMSE esitmate of the channel [26] [27] [28]. "
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