Pseudo-dynamic UWB WBAN Off-Body Radio Channel Measurements
This paper presents measurement results on pseudo-dynamic ultra wideband off-body wireless body area network radio channels. The measurements are performed in an anechoic chamber in a 2–8 GHz frequency band by utilizing a vector network analyzer. A dynamic walking sequence was modeled by a test person who took five different body postures which were each measured statically. As a result, when observed together, the five postures can be used to model a dynamic walking sequence as in a cinema film. The antennas were attached on left and right wrist, and left ankle. The off-body antenna node was set on a pole. The work was repeated for two prototype antenna types: dipole and double loop. The mean attenuations of the first arriving paths were noted to lie between −52… − 68 dB. No large differences were noted between the body postures. The link between left ankle and the pole had the largest attenuation. The averaged channel impulse response durations were noted to lie between eight to nine taps, where one tap corresponds to 0.167 ns in time. The dynamic range on the averaged link types shows values between 17…28 dB. No clear difference was noted in the performance between the antenna types.