Survey of Millimeter-Wave Propagation Measurements and Models in Indoor Environments

Abstract

The millimeter-wave (mmWave) is expected to deliver a huge bandwidth to address the future demands for higher data rate transmissions. However, one of the major challenges in the mmWave band is the increase in signal loss as the operating frequency increases. This has attracted several research interests both from academia and the industry for indoor and outdoor mmWave operations. This paper focuses on the works that have been carried out in the study of the mmWave channel measurement in indoor environments. A survey of the measurement techniques, prominent path loss models, analysis of path loss and delay spread for mmWave in different indoor environments is presented. This covers the mmWave frequencies from 28 GHz to 100 GHz that have been considered in the last two decades. In addition, the possible future trends for the mmWave indoor propagation studies and measurements have been discussed. These include the critical indoor environment, the roles of artificial intelligence, channel characterization for indoor devices, reconfigurable intelligent surfaces, and mmWave for 6G systems. This survey can help engineers and researchers to plan, design, and optimize reliable 5G wireless indoor networks. It will also motivate the researchers and engineering communities towards finding a better outcome in the future trends of the mmWave indoor wireless network for 6G systems and beyond.

Terahertz Wireless Channels: A Holistic Survey on Measurement, Modeling, and Analysis

“…Narrowband sounders are useful to obtain partial characteristics of the channel, for instance, attenuation and distortion resulting from multipath propagation and fading. The Tx of a narrowband sounder consists of the signal generator transmitting a sinusoidal continuous wave (CW) at the carrier frequency and the transmit antenna, while the Rx is composed of a receive antenna and a spectrum analyzer that can capture the received signal spectrum within an observation window spanning a few hundred of hertz [33].…”

“…Since the correlation-based method requires an expensive wideband digitizer to support a very high sampling rate (equal to the Nyquist rate), most current correlation-based THz sounders use sliding correlation, which trades off measurement duration with sampling rate [33]. In this approach, first introduced for cellular measurements by Cox [66], the sequence generated at the Rx side for the correlation process has a chip rate f chip smaller than the chip rate of the transmit signal f chip .…”

Overview of Planar Antenna Loading Metamaterials for Gain Performance Enhancement: The Two Decades of Progress

“…The millimeter-wave band (30-300 GHz) has recently acquired increasing attention due to its advantage of providing higher data rate transmissions. It has been proposed for achieving the 5G multi-gigabit applications [90], [91]. In the 2015 World Radio Communication Conference, the frequency range of 24.25 to 86 GHz had been proposed in the International Mobile Telecommunications for 2020 and beyond [92].…”

Evaluation of Radio Communication Links of 4G Systems

“…Other models, close-in, floating-intercept, and alpha-beta-gamma models, are used in [ 8 ]. These models are used also in [ 9 , 10 , 11 ]. The procedures of these models are presented in these two papers [ 8 , 9 , 10 ].…”

“…These models are used also in [ 9 , 10 , 11 ]. The procedures of these models are presented in these two papers [ 8 , 9 , 10 ]. The path loss model in [ 12 ] is based on the received signal strength indicator measurements.…”