1-1hit |
Ultra Wideband (UWB) communication system utilizing impulse signals is attractive technique which can achieve high data rate with low complexity and low power consumption. In this impulse based UWB system, lots of different shaped pulses have been considered to represent more information bits per symbol. In order to detect these different shaped UWB signals at the receiver, the synthesized template generation method using several elementary waveforms is effective. In this paper we design and analyze this synthesized template waveform instead of the conventional matched filter technique. The synthesis of UWB template waveform can be achieved as combinations of orthogonalized elementary waveforms with Fourier coefficients. By adjusting the number of elementary waveforms and their coefficients, it is possible to detect several types of UWB signals. The orders of approximation corresponding to different number of elementary waveforms are analyzed and the bit error rate properties are then investigated in AWGN and multipath fading channels. In addition, the proposed system can capture more energy by adjusting its coefficients adaptively under the multipath environment and reduce the effect of Intra-Pulse Interference (IPI) which is occurred when the propagation channel is not separable, that is, multipath components spaced closer than the typical pulse width. We show the design of the adaptive template synthesis method and its performance compared with conventional Rake receiver.