p and discriminate delays of arriving waves are large compared to the symbol between those signal 'directions' in an unambiguous way, duration, is also discussed. Clearly, fading statistics are which is not possible with merely planar arrays. This quite important for optimising the communication spherical array composed of 12 capacitively compensated scheme and for predicting the performance of the link. monopoles has been designed with a Galerkin piecewise Still, because numerous advantages would result if the sinusoidal basis function wire-grid program (Numerical channel fading behaviour could be accurately forecast, Electromagnetics Code (NEC2)) making use of delta-gap the potential of prediction techniques, algorithms and excitations. Therefore, the pentagonal parts of the applications has been analysed. Extensive measurement dodecaeder have been approximated by two concentric campaigns have been conducted over the last few years in pentagons and radially extending wires. The emphasis order to obtain statistical information on temporal and was on the minimisation of the effects of the feedlines on angular dispersion, including the characteristics of clus- both network parameters and radiation patterns as well ters and of diffusely scattered power, for a variety of as the coupling between the elements. The realised do- propagation scenarios or environments. The main results decahedral antenna, Figure 4.7-1, has coupling values and conclusions are outlined in Section 4.7.5. below -23 dB, while the simulations predict -22 dB. The matching, however, is not perfectly predicted (-18 dB 4.7.2 EM theory and diffuse in the 4900-5100 MHz band, while the program predicts scattering a reflection loss of less than -23 dB). Papers [TrSi02] and [TrSi03] use another commercial This section deals with the progress made in the field of Method of Moments (MoM) solver (WIPL) to compute both coupling and impedances of planar circular arrays of the electromagnetic behaviour of communication sys- monopoles designed around 5 GHz (4.