Spectrally Efficient UWB Pulse Shaping With Application in Orthogonal PSM

COPPE, Fed. Univ. of Rio de Janeiro
IEEE Transactions on Communications (Impact Factor: 1.99). 03/2007; 55(2):313 - 322. DOI: 10.1109/TCOMM.2006.887493
Source: IEEE Xplore


In this paper, we present a method to obtain a set of orthogonal pulses to be used in pulse-shape modulation (PSM) for ultra-wideband communications. The pulses are built as linear combinations of Hermite functions, which are shown to have unique advantageous features. Mathematical restrictions of orthogonality and spectral efficiency are introduced as guidelines to a fully explained search procedure to find the best set of pulses. Additionally, this procedure is adapted and used to find a single FCC-compliant pulse shape. A quaternary PSM scheme is implemented with orthogonal pulses obtained by the proposed method, and the results of a simulation are shown

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    • "Hermite functions have been proposed as modulating pulses in pulse-shape modulation for ultra-wideband (UWB) communication, mainly due to their maximal joint concentration in time and frequency, cf. [19] [15] [9] and references therein. The receiver of communication system often applies a filter with the modulation pulses as eigenfunctions corresponding to large eigenvalues, in order to suppress random noise that accumulates during transmission. "
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    • "Recently, the authors in [19] have compared the bandwidth requirement of the conventional SM scheme assumed to be employing raised-cosine filter/half-sine filter with that of the TOPS assisted SSK scheme employing Hermite polynomial based TOPS filter [20]. It was shown in April 26, 2012 DRAFT [19] that under stringent conditions on the energy containment, the bandwidth required by the TOPS assisted SM scheme is lesser than that of the conventional SM scheme. "
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