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Optimal Placement of Training for Frequency-Selective Block-Fading Channels

Overview The problem of placing training symbols optimally for orthogonal frequency-division multiplexing (OFDM) and single-carrier systems is considered. The channel is assumed to be quasi-static with a finite impulse response of length (L + 1) samples. Under the assumptions that neither the transmitter nor the receiver knows the channel, and that the receiver forms a minimum mean square error (MMSE) channel estimate based on training symbols only, training is optimized by maximizing a tight lower bound on the ergodic training-based independent and identically distributed (i.i.d.) capacity. For OFDM systems, it is shown that the lower bound is maximized by placing the known symbols periodically in frequency.

Further White Paper Details
Publisher	Cornell University	File Format	PDF, requires Acrobat Rdr 5
Date Published	August 2002	Downloads	14
Format	White Papers
Topics	Modems

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