Channel modelling and propagation measurements for a bodyworn 5.2 GHz terminal moving in the indoor environment

摘要

[Abstract]: Proposed applications for broadband wireless local areanetworks may include the use of bodyworn orhandportable terminals. The proximity of the user'sbody has a significant effect on the radio propagationcharacteristics through spatial filtering of the multipathchannel. This paper compares measurements andsimulations of a narrowband 5.2 GHz radio channelwith a fwed transmitter and a bodywom receiver. Themodelling technique was a site-specific ray-tracingsimulator incorporating a modified three-dimensionalradiation pattem of the bodyworn receiver. Two indoorenvironments were considered, an 18 m long corridorand a 42 m* office. The results show that the receivedpower envelope and local mean values are stronglydependent. on body shadowing in relation to the directray. In the corridor, 'the predicted non-line-of sight(NLOS) mean received powers was 13.6 dB lower thanfor line-of-sight (LOS). In the office, the predictedNLOS received power was 5.2 dB lower than LOS. Themeasured body shadowing effect was lower: 5.4 dB forthe corridor and 3.8 dB for the office. Further analysisof level crossing rate and average fade duration showedthat the prediction tool tended to underestimate thedegree of fading. This was attributed to the movementlimitations of the body model used.