Ultra-wideband (UWB) communications channel measurements - a tutorial review

This paper presents a comprehensive overview of Ultra-Wideband (UWB) measurements of all the empirical data available on various fading properties of the indoor radiowave communication channel. Our focus is on the essential propagation channel parameters which is used in the physics-based models. This overview is based on more than 50 measurement campaigns from 24 working groups in different countries including North-American, European and Asian, and more than 100 references (in total) mostly books and journals articles on the UWB propagation channels. The measurement campaigns utilize different multipath propagation measurement techniques including Direct-Pulse (DP), spread spectrum Sliding Correlator (SD) and Frequency Sweeping (FSW) in various environments office, laboratory, corridor, open areas (classroom, reading room, auditorium) and residential building to measure metrics: 1) Power-loss characteristics including Path-Loss (PL), large-scale fading and small-scale fading. 2) Temporal characteristics including multipath arrival rate, multipath delay spread (Power Delay Profile (PDP) and Root-Mean-Squared (RMS) delay spread) and temporal correlation. 3) Spatial characteristics including multipath Angle-of-Arrival (AOA) and spatial correlation across the receiver’s spatial aperture. 4) Frequency characteristics including Frequency-Selectivity (FSE) and Pulse-Distortion (PD). This tutorial overview is supported by a integrated summary on measurement results on each category. These analytic summaries lead to insights on UWB fading channel characterization and modeling.