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Recently, a measurement campaign for characterizing time-variant radio channels in city-canyon environments was conducted along a 2-km-long pedestrian shopping street in Shanghai. A passive sounding approach was adopted where a software-defined-radio platform is used as a receiver (Rx) to record downlink signals transmitted by base stations (BSs) in an in-service Universal Mobile Telecommunication
Recently, a measurement campaign for characterizing the channels in underground subway environments was conducted in Shanghai, China. Downlink signals transmitted by 46 universal mobile telecommunication system cells deployed along a 34-km-long subway were collected. Channel impulse responses are extracted from the data received in the common pilot channels, based on which parameters of multipath
In this contribution, a measurement campaign for high- speed-train (HST) channel is introduced where the down- link signals of in-service Long Time Evolution-Advanced (LTE-A) network deployed along the HST railway between Beijing to Shanghai are acquired. Channel impulse responses (CIRs) are extracted from received signals, and concatenated power delay profiles (CPDPs) are illustrated. According t
In this paper, a measurement campaign in high-speed-train (HST) environments is introduced where the downlink signals of an in-service Universal Mobile Terrestrial System (UMTS) deployed along a HST railway between Beijing and Shanghai were required by a single receiving antenna. Channel Impulse Responses (CIRs) are extracted from the data received in Common PIlot CHannels (CPICHs). The train spee
In this paper, a recently conducted measurement campaign for High-Speed-Train (HST) channels is introduced where the down-link signals of in-service Long Time Evolution-Advanced (LTE-A) networks deployed along a HST railway between Beijing to Shanghai were acquired. The channel impulse responses (CIRs) are extracted from the received Cell-specific Reference Signals (CRSs). The results show that, m
In this contribution, a recently conducted measurement campaign in underground subway environments is introduced. The downlink signals in an in-service UMTS network are collected in the subway carriage by using an Universal Software-defined Radio Peripheral (USRP) equipment and used to extract the channel impulse responses (CIRs) between a user equipment and UMTS stations. A high-resolution parame
Cellular-connected unmanned aerial vehicles (UAVs) have recently attracted a surge of interest in both academia and industry. Understanding the air-to-ground (A2G) propagation channels is essential to enable reliable and/or high-throughput communications for UAVs and protect the ground user equipments (UEs). In this contribution, a recently conducted measurement campaign for the A2G channels is in
Unmanned Aerial Vehicles (UAVs) have been widely used in military and civilian fields in the recent years. In order to give support to the vast amount of added value services, UAV communications have become a hot spot for the fifth generation (5G) and have a very broad development prospect. In this paper, based on the channel modeling results obtained by actual measurements, we evaluate the end-to
During the last few years, with the decrease of their sizes and costs, Unmanned Aerial Vehicles (UAVs) became more feasible for their use in general-purpose applications. As an important basis for UAV applications, the Air-to-Ground (A2G) radio propagation channel has gained attention in the channel modeling literature. However, whereas the A2G propagation channel is inherently dynamic (time-varyi
We propose a multivariate log-normal distribution to jointly model received power, mean delay, and root mean square (rms) delay spread of wideband radio channels, referred to as the standardized temporal moments. The model is validated using experimental data collected from five different measurement campaigns (four indoor scenarios and one outdoor scenario). We observe that the received power, th
Due to the decrease in cost, size, and weight, unmanned aerial vehicles (UAVs) are becoming more and more popular for general-purpose civil and commercial applications. Provision of communication services to UAVs both for user data and control messaging by using off-the-shelf terrestrial cellular deployments introduces several technical challenges. In this article, an approach to the air-to-ground
This paper investigates the wideband channel characteristics obtained in a classroom and a hall indoor scenarios at 2-4, 9-11 and 27-29GHz. A virtual uniform circular array (UCA) based channel sounding system was utilized to capture wideband spatial channel characteristics. The propagation parameters of multipath components (MPCs) were estimated by using a high resolution parameter estimation (HRP
In parallel with the decrease in cost, size and weight of Unmanned Aerial Vehicles (UAVs) and the increase of their flight autonomy, many commercial applications are rapidly arising. Most of those applications rely on a communications system between a terrestrial base station and the UAV. Due to the UAV movement, time-variant channel models are required. In this article, we propose a geometrical m
In a wireless communication system, the radio propagation channel is a complicated component to characterise. Channel sounding equipment thus has to meet specific criteria to extract the desired channel parameters. In this study, the authors outline the development and validation of a vector network analyser (VNA) based channel sounder for the frequency range from 1 to 50 GHz using radio-over-fibr
Millimeter-wave with ultrawide bandwidth available and ability to pack massive number of antennas in a small area is considered the key enabler for future generation communication systems. Accurate understanding and modeling of the ultrawideband propagation channel with large-scale array configuration is essential. In this contribution, a realistic spherical-propagation signal model considering th
Massive multiple-input multiple-output (MIMO) is a key technology for 5G wireless communications since it can improve network throughput, capacity, spatial efficiency, etc. utilizing large-scale antenna arrays. In this paper, we study the direction of departure (DOD) and direction of arrival (DOA) power spectra and the angular spreads for suburban line-of-sight (LoS) environment. Our study is base
The unmanned-aerial-vehicle (UAV) has attracted great interests in both civil and military applications, due to its low cost, flexibility and ability to establish seamless coverage. In this paper, a Universal Software-defined Radio Peripheral (USRP) based channel sounding system for characterizing the UAV communication channel is introduced, which can be applied in both active and passive measurem
In this article, a novel vector network analyzer (VNA)-based ultrawideband (UWB) channel sounder using radio-over-fiber (RoF) techniques is presented. Benefiting from the usage of optical fiber cable, the measurement range and the dynamic range are significantly increased compared with the conventional coaxial-based VNA system. Specifically, using RoF increases the dynamic range to a maximum of 11
Low altitude unmanned aerial vehicle (UAV)-aided applications are promising in the future generation communication systems. In this paper, a recently conducted measurement campaign for characterizing the low-altitude air-to-ground (A2G) channel in a typical Long Term Evolution (LTE) network is introduced. Five horizontal flights at the heights of 15, 30, 50, 75, and 100 m are applied, respectively
Vector network analyzer (VNA) has been extensively utilized for radio channel sounding purposes. Due to its slow channel sounding speed, it has been mainly used for channel measurements in static propagation scenarios. The main limitation with VNA based channel sounder is its small measurement range, due to signal attenuation in the coaxial cable setup. Employing radio over fiber (RoF) can effecti
