A novel modulation diversity assisted ultra wideband communication system,” presented at the

Abstract—In this paper, a novel modulation diversity assisted (MDA) ultrawideband (UWB) communication system is proposed. Pulse position modulation and pulse amplitude modulation are ap-plied to successive transmitted pulses alternately. The resulting modulation diversity helps to overcome channel estimation diffi-culties in typical UWB channels and permits low complexity re-ceiver design. If every two consecutive pulses are grouped together, some connections with a transmitted reference (TR) system are demonstrated. But significant advantages of the proposed system are observed in smooth spectrum and increased data rate. Uti-lizing statistical properties of the modulated signals and inherent diversity, different receivers are designed for such a system. A con-ceptual receiver performs symbol detection using neighboring re-ceived signal to construct the template, while an advanced receiver uses a block of received signals to obtain a better template. The ad-vanced receiver may continue to improve the template as ongoing detected symbols are available. A maximum likelihood estimator is also derived as a performance benchmark. The conceptual receiver shows slightly better performance than a conventional TR receiver while the advanced receiver shows comparable performance of the receiver using a maximum likelihood template estimator. Perfor-mance of the advanced receiver is studied both analytically and numerically. In a case of severe multipath channel distortion that results in interference between received signals from consecutive transmitted pulses, a corresponding template estimator and dif-ferent receivers are also presented with detection performance nu-merically studied. Index Terms—Intersymbol interference, low complexity, modu-lation diversity, optimum template estimation, transmitted refer-ence (TR), ultrawideband (UWB). I