5G 3GPP-like Channel Models for Outdoor Urban Microcellular and Macrocellular Environments

For the development of new 5G systems to operate in bands up to 100 GHz, there is a need for accurate radio propagation models at these bands that currently are not addressed by existing channel models developed for bands below 6 GHz. This document presents a preliminary overview of 5G channel models for bands up to 100 GHz. These have been derived based on extensive measurement and ray tracing results across a multitude of frequencies from 6 GHz to 100 GHz, and this document describes an initial 3D channel model which includes: 1) typical deployment scenarios for urban microcells (UMi) and urban macrocells (UMa), and 2) a baseline model for incorporating path loss, shadow fading, line of sight probability, penetration and blockage models for the typical scenarios. Various processing methodologies such as clustering and antenna decoupling algorithms are also presented.Comment: To be published in 2016 IEEE 83rd Vehicular Technology Conference Spring (VTC 2016-Spring), Nanjing, China, May 201

On the design of multiuser codebooks for uplink SCMA systems

Sparse code multiple access (SCMA) is a promising uplink multiple access technique that can achieve superior spectral efficiency, provided that multidimensional codebooks are carefully designed. In this letter, we investigate the multiuser codebook design for SCMA systems over Rayleigh fading channels. The criterion of the proposed design is derived from the cutoff rate analysis of the equivalent multiple-input multiple-output system. Furthermore, new codebooks with signal-space diversity are suggested, while simulations show that this criterion is efficient in developing codebooks with substantial performance improvement, compared with the existing ones

Performance Analysis of 5G Transmission over Fading Channels with Random IG Distributed LOS Components

Mathematical modelling of the behavior of the radio propagation at mmWave bands is crucial to the development of transmission and reception algorithms of new 5G systems. In this study we will model 5G propagation in nondeterministic line-of-sight (LOS) conditions, when the random nature of LOS component ratio will be observed as Inverse Gamma (IG) distributed process. Closed-form expressions will be presented for the probability density function (PDF) and cumulative distribution function (CDF) of such random process. Further, closed-form expressions will be provided for important performance measures such as level crossing rate (LCR) and average fade duration (AFD). Capitalizing on proposed expressions, LCR and AFD will be discussed in the function of transmission parameters

Multifrequency Wireless Channel Measurements and Characterization in Large Indoor Office Environments

This article performs extensive channel measurements and characteristics analysis to investigate large-scale fading (LSF) and small-scale fading (SSF) of wireless local area network (WLAN) channels in large indoor office environments. Multifrequency single-input-single-output (SISO) channel measurements are conducted at 3, 5.5, and 6.5 GHz under the same conditions to explore the frequency dependence of LSF, delay spread (DS), and $K$ -factor (KF). Then, SISO channel measurements with different half-power beamwidths (HPBWs) of antennas are performed at 5.5 GHz in access point (AP) to user equipment (UE) and AP-to-AP scenarios. The effects of antenna HPBW on LSF, DS, and KF are investigated, thereby inspiring the AP deployment in high-density (HD) scenarios. Finally, $32 \times 64$ multiple-input-multiple-output (MIMO) channel measurements at 5.5 GHz are conducted to study the SSF of the time nonstationarity and multilink correlation. The time nonstationarity, including the parameters' drifting and cluster evolution caused by the movement of the UE, is verified by the measurement results. Multilink correlations are illustrated from the perspectives of the angular power spectral density (APSD) and correlation matrix collinearity (CMC). The results show that the distance between users and separation angle can affect the multilink correlation.</p

Heuristic Coordinated Beamforming for Heterogeneous Cellular Network

Heterogeneous cellular networks (HetNets) is key technology in 5G used to tackle the ever increasing demand of data rate. The most critical problem of HetNet is interference. In this paper, we utilize the coordinated beamforming technique to mitigate the interference problem. We also suggest that reference signal receive power (RSRP) based cell association scheme has limitation when applied to multi-tier cellular networks. Therefore, we propose a new cell selection approach for HetNets, which is based on average channel gain. Simulation results of our designed beamformers show improvement over other schemes in terms of achievable information rates per cell

Recent Advances in RF Propagation Modeling for 5G Systems

Stefanovic, M.; Panic, SR.; De Souza, RAA.; Reig, J. (2017). Recent Advances in RF Propagation Modeling for 5G Systems. International Journal of Antennas and Propagation (Online). 2017(4701208):1-5. doi:10.1155/2017/4701208S152017470120

Green Hybrid Satellite Terrestrial Networks: Fundamental Trade-Off Analysis

With the worldwide evolution of 4G generation and revolution in the information and communications technology(ICT) field to meet the exponential increase of mobile data traffic in the 2020 era, the hybrid satellite and terrestrial network based on the soft defined features is proposed from a perspective of 5G. In this paper, an end-to-end architecture of hybrid satellite and terrestrial network under the control and user Plane (C/U) split concept is studied and the performances are analysed based on stochastic geometry. The relationship between spectral efficiency (SE) and energy efficiency (EE) is investigated, taking consideration of overhead costs, transmission and circuit power, backhaul of gateway (GW), and density of small cells. Numerical results show that, by optimizing the key parameters, the hybrid satellite and terrestrial network can achieve nearly 90% EE gain with only 3% SE loss in relative dense networks, and achieve both higher EE and SE gain (20% and 5% respectively) in sparse networks toward the future 5G green communication networks