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This paper presents some considerations on the design, characterization and optimization of UWB (Ultra WideBand) antennas for consumer communication equipment. As a first step a method to extract the spatio-temporal UWB antenna characterization from a FDTD simulation is given. Thereafter, the shape of a planar monopole is optimized to provide broadband matching. This is followed by the integration of latter antenna into a model of a DVD player and the impact of this integration on the antenna performance is evaluated. Finally, the transfer function of the complete system is extracted and used for indoor propagation modeling in an exemplary living home environment. The results show that the antenna integration into the DVD-chassis results into a directive radiation pattern that shows a significant frequency dependency. When this antenna is used for the propagation modeling, a single frequency ray-tracing simulation shows significant variation in the radiated power distribution in the room as a result of the directive pattern. When the received power is averaged over a larger bandwidth, the coverage becomes more smooth mainly due to the frequency dependency of the radiation pattern and frequency dependent propagation effects. Indeed, comparing the results of the integrated antenna to the case of the ideal isotropic radiator, no major disadvantages can be discerned anymore.

The specific absorption rates (SAR) determined computationally in the specific anthropomorphic mannequin (SAM) and anatomically correct models of the human head when exposed to a mobile phone model are compared as part of a study organized by IEEE Standards Coordinating Committee 34, SubCommittee 2, and Working Group 2, and carried out by an international task force comprising 14 government, academic, and industrial research institutions. The detailed study protocol defined the computational head and mobile phone models. The participants used different finite-difference time-domain software and independently positioned the mobile phone and head models in accordance with the protocol. The results show that when the pinna SAR is calculated separately from the head SAR, SAM produced a higher SAR in the head than the anatomically correct head models. Also the larger (adult) head produced a statistically significant higher peak SAR for both the 1- and 10-g averages than did the smaller (child) head for all conditions of frequency and position.