The effect of time-reversal filter on UWB-IR communications

Recently ultra wideband impulse radio (UWB-IR) has been attracted much attention on short-range wireless communication, because UWB-IR has abilities to achieve high transmission rate, low power consumption and so on. Considering access-point (AP) terminal pair, as the transmission power of AP is limited to -41.3dBm/MHz from FCC regulation, result in low received signal intensity, thus time-reversal (TiR) scheme based on pre-rake combine technique is suggested as a promising solution to improve Eb/N0 of terminal and also keep terminal structure simple. In our previous work, it has been experimentally discussed that longer TiR filter length (number of combined multi-path) takes better Eb/N0 [1]. However when in high transmission rate, the longer filter length should also take the harder inter-symbol interference (ISI) resulting in degradation of bit error rate (BER). In this work under many kinds of transmission rates, the optimum TiR filter length has been discussed by measurement and simulation.