Maximum-diversity transmissions over time-selective wireless channels
نویسندگان
چکیده
Carrier frequency-offsets and mobility-induced Doppler shifts introduce time-selectivity in wireless links. Doppler-RAKE receivers have been developed for collecting the resulting diversity gains only for spread-spectrum systems. Relying on a basis expansion model of time-selective channels, we find that the maximum achievable Doppler diversity is determined by the rank of the correlation matrix of the channel’s expansion coefficients. We also prove that RAKE reception can not collect maximum diversity gains, unless the transmission is appropriately designed. Finally, we design such block precoded transmissions to ensure maximum diversity gains, and provide thorough simulations to corroborate our theoretical findings.
منابع مشابه
Block space-time antenna precoding/decoding for generalized multicarrier communications in unknown multipath
Transmit antenna diversity has been exploited recently to develop high performance space-time coders and simple maximum-likelihood decoders for transmissions over known at fading channels. Relying on block precoding, this paper develops generalized space-time coded multicarrier transceivers appropriate for wireless propagation over frequency-selective (and perhaps unknown) multipath channels. M...
متن کاملSpace-time coded transmissions with maximum diversity gains over frequency-selective multipath fading channels
In this paper, we study space-time block coding for single carrier block transmissions through frequency selective multipath channels of order L. We prove that maximum diversity of order 2(L + 1) can be achieved with two transmit and one receive antennae. We show that simple linear receiver processing can achieve full antenna diversity gains, and investigate the performance versus complexity tr...
متن کاملBlock differentially encoded OFDM with maximum multipath diversity
This letter proposes a novel block differentially encoded OFDM for multicarrier transmissions over frequency-selective fading channels. Choosing appropriate system parameters, we divide the set of correlated subchannels into subsets of independent subchannels. Within each subset, differential unitary space-time modulation is performed by treating each subchannel as a transmit-antenna. In additi...
متن کاملSingle-Carrier Frequency-Domain Equalization for Orthogonal STBC over Frequency-Selective MIMO-PLC channels
In this paper we propose a new space diversity scheme for broadband PLC systems using orthogonal space-time block coding (OSTBC) transmission combined with single-carrier frequency-domain equalization (SC-FDE). To apply this diversity technique to PLC channels, we first propose a new technique for combining SC-FDE with OSTBCs applicable to all dispersive multipath channels impaired by impulsive...
متن کاملTransmit antennae space-time block coding for generalized OFDM in the presence of unknown multipath
Transmit antenna diversity has been exploited recently to develop high-performance space–time coders and simple maximum-likelihood decoders for transmissions over flat fading channels. Relying on block precoding, this paper develops generalized space–time coded multicarrier transceivers appropriate for wireless propagation over frequency-selective multipath channels. Multicarrier precoding maps...
متن کامل