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INTRODUCTIONNew microwave communication services have raised the interest in base station antennas capable of radiating an omnidirectional pattern in the aziniuthal plane as it is tlie case for cellular conimunications. Those antennas usually comprise linear dipole or slot arrays and, at higher frequencies, printed antenna arrays. Although such arrays inay produce adequate radiation patterns, main disadvantages of their use rest on reduced bandwidths and increasing losses with frequency due to phase and power control circuits.Alternatively, at microwave or millimetric ranges, one niay employ reflector antenna configurations for base stations, comprising reflector surfaces shaped in order to radiate uniformly in tlie horizontal plane while taking into account free -space attenuation via cosecant squared -like power patterns in vertical planes, with radiated energy concenmted below the horizon line for reduced interference. 'I'he main characteristics of two such configurations are reviewed in what follows. REFLECTOR ANTENNA CONFlGURATlONSThe antenna configuration shown in Fig. I comprises a (circularly symmetrical) conically shaped reflector surface fed by an axial horn. Concentrical circular sections of tlie feed horn have their radii chosen (Ap

This paper discusses the experimental polarization characterization of multipath signals propagating in cellular communications environments. Results and analysis are presented for outdoor and indoor acquired data. The experimental conditions and setup developed for data acquisition are described.

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