標題: | On the performance of using multiple transmit and receive antennas in pulse-based ultrawideband systems |
作者: | Wang, LC Liu, WC Shieh, KJ 電信工程研究所 Institute of Communications Engineering |
關鍵字: | pulse position modulation (PPM);time-switched transmit diversity (TSTD);ultrawideband (UWB) |
公開日期: | 1-十一月-2005 |
摘要: | This paper presents an analytical expression for the signal-to-noise ratio (SNR) of the pulse position modulated (PPM) signal in an ultrawideband (UWB) channel with multiple transmit and receive antennas. A generalized fading channel model that can capture the cluster property and the highly dense multipath effect of the UWB channel is considered. Through simulations, it is demonstrated that the derived analytical model can accurately estimate the mean and variance properties of the pulse-based UWB signals in a frequency-selective fading channel. Furthermore, the authors investigate to what extent the performance of the PPM-based UWB system can be further enhanced by exploiting the advantage of multiple transmit antennas or receive antennas. Numerical results show that using multiple transmit antennas in the UWB channel can improve the system performance in the manner of reducing signal variations. However, because of already possessing rich diversity inherently in the UWB channel, using multiple transmit antennas does not provide diversity gain in the strict sense [i.e., improving the slope of bit error rate (BER) versus SNR] but can possibly reduce the required fingers of the RAKE receiver for the UWB channel. Furthermore, because multiple receive antennas can provide higher antenna array combining gain, the multiple receive antennas technique can be used to improve the coverage performance for the UWB system, which is crucial for a UWB system due to the low transmission power operation. |
URI: | http://dx.doi.org/10.1109/TWC.2005.858009 http://hdl.handle.net/11536/13097 |
ISSN: | 1536-1276 |
DOI: | 10.1109/TWC.2005.858009 |
期刊: | IEEE TRANSACTIONS ON WIRELESS COMMUNICATIONS |
Volume: | 4 |
Issue: | 6 |
起始頁: | 2738 |
結束頁: | 2750 |
顯示於類別: | 期刊論文 |