Cyclic Prefix Signaling for Pulse Shape Modulation UWB RAKE Receivers

Abstract

Combining transmission of ultra wideband pulses, organized in blocks, with the inclusion of cyclic prefixing pulses yields a pulsewidth periodic signal at the receiver. Although unknown, this signal fits perfectly the diversity exploitive architecture of a RAKE receiver. Aiming to profit from this signal arrangement, we propose a pulse shape modulation system employing a RAKE receiver that estimates this periodic signal during a training interval and uses the estimated values for detection of data symbols. Our proposal relies on the invariability of the multipath propagation channel during the transmission of a UWB packet, the adequate application of the cyclic prefix, and the fact that different transmitted pulses result in different periodic signals at the receiver. This system is equivalent to transforming the multipath nature of the UWB propagation channel into a multichannel digital communications affected solely by additive noise. Our proposal is important because it ameliorates the performance of a pulse shape modulation RAKE receiver. On the other hand, the cost of our proposed system resides in the inefficiencies product of the cyclic prefix inclusion.