Measurements and analysis of the indoor wideband millimeter wave wireless radio channel and frequency diversity characterization

Abstract

This paper presents results of frequency domain measurements conducted to evaluate the effectiveness of frequency diversity in mitigating the effects of multipath fading in indoor microcellular channels employing omni-directional receive antenna in the band 63.4-65.4 GHz. The performance of frequency diversity for 155 MHz and other channel bandwidths to accommodate modulated signals with data rates up to 155 Mb/s is presented. Results are obtained using maximum selection combining and presented as functions of frequency separation between the diversity branch signals. Improvement in the level crossing rate and average fade duration is given together with improvement in the -Rician factor. The root mean square (rms) delay spread ( rms ) and coherence bandwidth ( c ) of the channel are also presented as functions of distance between terminals. Values of c for correlation levels of 0.9, 0.7, and 0.5 are given together with the cumulative distribution functions of rms . The levels below which the coherence bandwidth stays for 90% of receiver positions are estimated. Measurements were repeated under identical test conditions but with the receive omni-directional antenna replaced by a directional horn in order to characterize the effect of the receive antenna radiation pattern on the indoor radio channel characteristics.Index Terms-Coherence bandwidth, diversity, indoor channel, millimeter wave, radio-wave propagation, RMS delay spread, wireless LAN.

Blockage and directivity in 60 GHz wireless personal area networks: from cross-layer model to multihop MAC design

“…In terms of the channel model we use, while our diffraction model is based on fundamental physics, we are motivated by the extensive body of knowledge on mm wave propagation measurement and modeling. Measurement campaigns in indoor environments include [20]- [29]. For typical indoor environments with omnidirectional antennas, specular reflections from surfaces are dominant contributors to the received signal power as compared with diffraction or scattering [24], [30]- [32].…”

Millimeter-Wave Communications: Physical Channel Models, Design Considerations, Antenna Constructions, and Link-Budget

“…Figure 22 shows three CIR main components, namely a high gain path representing the LOS component and two other low gain NLOS spatial-clusters, where each spatialcluster has multiple time-clusters, since the different MPCs have different Time-of-Arrivals (ToA), as described by the n-th cluster delay τ n cl and the AoA characteristics. On the same note, the different measurements conducted at multiple mmWave frequency bands reported that the received PDPs and PAPs were detected in spatial-clusters and time-clusters [14], [44], [54], [69], [121], [225]. The concept of timeclusters and spatial-clusters was further extended in [72], [76], [79], [80], [105], [211], where multiple received components of a specific time-cluster were observed throughout multiple spatial-clusters, which are also referred to as spatial lobes.…”

“…The spatio-temporal characteristics of the 60 GHz channel were also studied in [14], [28], [66], [69], [120], [121], [125], [142], [166], [175], [206], where the model of the indoor 60 GHz channel is based on the TSV [67] and on the extended-SV [171], [172] channel models. The general double-directional wideband CIR is given by:…”

Measurement and Analysis of Channel Characteristics in Reflective Environments at 3.6 GHz and 14.6 GHz

“…The antennas were mounted on wooden tripods with a small section of metal behind the directional antennas, which does not influence the pattern. Calibration was performed in an anechoic chamber to compensate the frequency response of antennas and cables as suggested in [13]. These two measured bands were free from interference during the measurement campaign, as confirmed by measurements with a spectrum analyzer (PSA E4445A, Agilent, Santa Clara, CA, USA).…”