Efficient channel estimation for OFDM modulations with transmit diversity
نویسندگان
چکیده
This paper considers the use of implicit pilots for channel estimation in OFDM schemes (Orthogonal Frequency Division Multiplexing) with transmit diversity. To cope with the interference levels between data and pilots, we propose an iterative receiver with joint detection and channel estimation. For the first iteration, the channels are estimated by averaging the received signal over several blocks; for the remaining iterations, enhanced channel estimates are obtained by considering the data symbols as extra pilots. Our performance results show that this technique allows the use of low-power pilots, with performances close to the ones with perfect channel estimation.
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