EFFECTS OF CHOICES OF PULSE SHAPES, MODULATION, RANDOMIZATION METHODS AND CODING ON THE PERFORMANCE CHARACTERISTICS OF ULTRA WIDEBAND WIRELESS COMMUNICATION SYSTEMS

摘要

This paper presents a review of topics of particular importance to the design, interference effects, and performance characteristics of Ultra Wideband (UWB) Wireless Communication Systems. These topics include pulse shaping, modulation, randomization and channelization, and coding for shaping the power spectral density (PSD). Investigated are the effects of the design choices of these on interference into and by other communication systems, and considerations of the reasonable complexity of implementation of UWB communication systems. Pulse shapes for UWB communications that have been reported in literature are described first and their characteristics, advantages and shortcomings discussed. A treatment of modulation schemes for UWB communications is presented, and power spectral densities of random time-hopping spread UWB signals without and with timing jitter are summarized. Methods for shaping the power spectral density of UWB signals are then described. Research problems to be investigated and a concluding discussion ends the paper.