A new multiple-antenna weighting scheme is proposed to improve the problem of inter-symbol-interference suppression in high data-rate UWB systems. When the transmitter knows the full channel state information of each sub-channel
the coefficients of the pre-processing fingers of each antenna and equivalent channel responses are obtained through channel coefficients reversal. Therefore
the final equivalent channel impulse response at the receiver is determined by the multiple-antenna weighting coefficients. The ratio of the received signal to interference-noise can be maximized in the sampled peak using the generalized Rayleigh quotient method. When the proposed scheme is used
only one antenna is needed at the receiver to obtain a trade-off between the multi-path energy capture and the ISI suppression. Simulation results and comparisons with the simple antenna combining scheme show that the proposed scheme achieves at least 2 dB BER performance improvement in a system with four transmit antennas.
LIAO Xuewen, REN Pinyi, ZHU Shihua, et al. An ultra-wideband transmitted-reference receiver under inter-symbol Interference [J]. Journal of Electronics and Information Technology,2008, 30(4):805-808.
ZHANG Jian, HU Hanying, WANG Tao, et al. Code-orthogonalized transmitted-reference chirp ultra-wideband system with active spectrum compressed structure [J]. Journal of Beijing University of Posts and Telecommunications, 2010, 33(6):107-111.
ESMAILZADEH R. Pre-RAKE diversity combination for direct sequence spread spectrum mobile communications systems [J]. IEICE Transactions on Communication, 1993, 76(8): 1008-1015
ESMAILZADEH R, SOUROUR E, NAKAGAWA M. PreRAKE diversity combining in time-division duplex CDMA mobile communications [J]. IEEE Transactions on Vehicular Technology, 1999, 48(3): 795-801.
CAO Wei, NALLANATHAN A, CHAI C C. On the tradeoff between data rate and BER performance of Pre-RAKE DS UWB system[C]∥Proceedings of IEEE Global Telecommunications Conference. Piscataway, NJ, USA: IEEE, 2006: 1-5.
ELHAM T, JAN M, SCHOBER R, et al. Pre-equalization for MISO DS-UWB systems with Pre-RAKE combining [J]. IEEE Transactions on Wireless Communications, 2009, 8(3): 4861-4866.
MOHSENIAN-RAD A H, MIEZNER J, SCHOBER R, et al. Pre-equalization for Pre-RAKE DS-UWB systems with spectral mask constraints [J]. IEEE Transactions on Communications, 2011, 59(3): 780-791.
MO Shaomin, GUO Nan, ZHANG John, et al. UWB MISO time reversal with energy detector receiver over ISI channels [C]∥Proceedings of IEEE Consumer Communications and Networking Conference. Piscataway, NJ,USA: IEEE, 2007:629-633.
FOERSTER J. Channel Modeling Sub-Committee report final, IEEE P802. 15-02/368r5-SG3a [R]. Los Alamitos, CA, USA: IEEE P802.15 Work Group for Wireless Personal Area Networks, 2002.
ZHAO Shiwei, LIU Huaping. Transmitter-side multipath preprocessing for pulsed UWB systems considering pulse overlapping and narrow-band interference[J]. IEEE Transactions on Vehicular Technology, 2007, 56(6): 3502-3510.
BHARADWAJ V, BUEHRER R. An interference suppression scheme for UWB signals using multiple receive antennas [J]. IEEE Communications Letters, 2005, 9(6): 529-531.
TRUNG K N, HIEU N, ZHENG Feng, et al. Spatial correlation in SM-MIMO-UWB systems using a pre-equalizer and pre-rake filter [C]∥Proceedings of 2010 IEEE International Conference on Ultra-Wideband(ICUWB).Piscataway,NJ,USA: IEEE, 2010: 1-4.