WIRELESS FLEXIBLE PERSONALIZED COMMUNICATIONS	COST 259
Working Groups

WG 2 - PROPAGATION AND ANTENNAS 
(Chairman: Prof. E. Bonek, Technical University of Vienna, A)
 

The following topics are examined within the Group, from both theoretical and experimental standpoints:

New modelling approaches for UHF and microwave bands, based on the direct solution (using fast computing parallel machines) of Maxwell's equations (for example, the Finite Elements Method (FEM), the Finite Differences in the Frequency or Time Domain Method (FD or FD-TD), the Transmission Line Matrix Method (TLM));

As spectrum at 5.2 GHz, 17.2 GHz and at 40 and 60 GHz has been allocated by CEPT to HIPERLAN and MBS, models will be studied for short range communications in the high microwave and millimetre-wave bands (microcellular and in-building coverage, penetration losses, tree effects, influence of obstructions and car traffic, etc.);

Comparisons between the effectiveness in different situations between empirical/statistical and electromagnetic/deterministic models (ray tracing);

Measurements will be performed, to validate the models, using ad-hoc channel sounders, and to get statistics on wideband parameters to be used for system simulations; this will allow the addition of new features that might improve significantly the efficiency of the computations, while retaining the required accuracy.

In the area of antennas, several topics will be examined:

Studies on the effects of the surrounding environment on base station antenna radiation pattern (masts, poles, walls, etc.);

Investigation about intelligent (smart) and adaptive Base Station antennas (in terms of their capability of suppression of interferences, pattern reconfigurability, dual polarisation, etc.);

Investigation on the possibility of using fiberoptic technologies for antenna feeding purposes in the mm-wave band;

Macro and micro diversity techniques, with particular attention to space diversity (detection of angles of arrival of multipath components) and polarisation diversity (orthogonal, slant), in order to optimise the link performance;

Feasibility of various kinds of combined analog/digital beamforming networks for high bit rate transmissions, as it is expected that even very fast ASIC's will not be able to perform the digital processing required to follow high bandwidths in real time; therefore, an optimal distribution between analog and digital parts should be investigated in detail.

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