Indoor channel characterization of diversity-based nomadic wireless systems

This paper aims at characterizing the wireless channel for nomadic diversity-based systems operating at 1.9 GHz. Using a 1 × 2 wideband measurement chain, four indoor environments have been investigated: a corridor, a small office, an electrical engineering laboratory, and an industrial hall. The measurement equipment is constituted by an 80-MHz transmitter. At the receiver, two omnidirectional antennas are connected to a wideband channel sounder through a switch, in order to measure an estimate of the instantaneous vector channel. Special attention is given to the experimental procedure itself, so as to take into account the specificity of nomadic systems (as opposed to usual mobile systems). The measurement analysis reveals that the shadowing, Ricean K-factor and delay-spread are lognormally distributed. A path-loss model is derived, and cross-correlations between K-factor, delay-spread and shadowing are analyzed. The channel correlations at the user terminal or at the access point are also derived, and related to the individual channel characteristics.