Alamouti-type space-time coding for free-space optical communication with direct detection
IEEE Transactions on Wireless Communications
IEEE Transactions on Wireless Communications
Error performance of pulse-based ultra-wideband MIMO systems over indoor wireless channels
IEEE Transactions on Wireless Communications
Full-diversity, high-rate space-time block codes from division algebras
IEEE Transactions on Information Theory
Perfect Space–Time Block Codes
IEEE Transactions on Information Theory
IEEE Transactions on Information Theory
A simple transmit diversity technique for wireless communications
IEEE Journal on Selected Areas in Communications
IEEE Journal on Selected Areas in Communications
Hi-index | 0.00 |
In this paper, we consider the problem of applying the Multiple-Input-Multiple-Output (MIMO) techniques on Impulse-Radio Time-Hopping Ultra-Wideband (IR-TH-UWB) communications. In particular, we propose two novel Space-Time (ST) block codes that are suitable for UWB. The proposed encoded MIMO-UWB schemes present the main advantage of conveying the information only through the positions of the very short unipolar UWB pulses. The constraint of unipolar transmissions keeps the transceiver structures very simple since it imposes no additional constraints on the RF circuitry to control the amplitudes or the phases of the sub-nanosecond UWB pulses. Consider the case where the transmitter is equipped with P antennas and where M PPM modulation positions are available. The first proposed scheme achieves a full transmit diversity order for M ≥ P while transmitting at the rate of log2(M) bits Per Channel Use (PCU). The second scheme is fully diverse with any number of antennas and transmits at a rate of M log2(P)/P bits PCU. The proposed codes permit to achieve different levels of compromise between complexity and performance since scheme 1 necessitates M-dimensional Maximum-Likelihood (ML) decoding while scheme 2 necessitates MP-dimensional decoding. We also present a comprehensive analysis on the enhancement in terms of the data rate achieved at a certain communication distance based on realistic indoor channel models and on an exact system model that takes inter-pulse-interference and inter-symbol-interference into consideration.