Millimetric wavelengths radiowave propagation for line-of-sightindoor microcellular mobile communications

摘要

Discusses millimeter waves for indoor microcellularncommunications. The results of propagation experiments conducted at 60.4nGHz (the oxygen absorption band) and 38.25 GHz to determine multipathncharacteristics in a number of indoor microcell channels employingnomnidirectional antennas are presented. Cumulative distributionnfunctions for received signal envelope, as well as corresponding powernspectra are given. In addition, a comparison between the fadingnstatistics measured at 60.4 GHz and 38.25 GHz under similar conditionsnis made. The change in multipath characteristics due to the presence ofndifferent building materials is also illustrated. A ray model isndeveloped to represent indoor microcell propagation by considering andirect ray plus rays which have undergone single and double reflectionsnfrom the walls. Specular floor-reflected and ceiling-reflected rays arenincluded when the antennas radiation pattern does not preclude them.nUsing this simple model, the signal variations and the amplitude ofnreflected rays with respect to the line of sight (LOS) ray as functionsnof mobile receiver position are predicted and used to assist inninterpreting experimental results. Theoretical results are found to benin good agreement with measured ones, with the model also being used tonpredict structure-induced root mean square (rms) delay spread alongnreceiver routes in an indoor microcell environment. This parameter is anmeasure of multipath conditions in a mobile radio channel and isninversely proportional to the maximum usable data signalling rate of anchannel