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This paper presents the scheme of a software planing tool for single microcells of broadband radio access systems operating at millimeter waves, providing local multipoint distribution services (LMDS), particularly in urban or suburban areas. The aim of this planing tool is to provide operators with information, which supports the assessment of the profitability by calculating link budgets and the area coverage and by roughly estimating the maximum number of potential customers, i.e. the total number of households in a~certain area, as well as the number of customers (households) which will actually be covered from a site. A household is here considered as a single apartment or flat, thus a building usually consists of several households. This novel household-estimation model is able to estimate the number of households based only on the 3D-data of buildings, without using residential data. Besides the optimization of line-of-sight (LOS) coverage, also the possibility is considered to enhance the coverage into shadowed areas by using optimized reflectors as passive repeaters up to distances of 1 km from the base station, depending on the system margin and the rain climate zone. All calculations are based on 3D-databases of both, buildings and vegetation.

This letter deals with the excitation of UHF radio waves in tunnels. It is found that the antenna position and the antenna gain are two major factors that affect the excitation of radio waves in tunnels. The antenna in the middle position and with high gain is preferable. Furthermore, the enhancement of the radio signal levels in the NLOS region of the tunnel by a passive reflector is simulated. ©1999 John Wiley & Sons, Inc. Microwave Opt Technol Lett 22: 408–410, 1999 [ABSTRACT FROM AUTHOR]