Massive MIMO is a Reality -- What is Next? Five Promising Research Directions for Antenna Arrays

Massive MIMO (multiple-input multiple-output) is no longer a "wild" or "promising" concept for future cellular networks - in 2018 it became a reality. Base stations (BSs) with 64 fully digital transceiver chains were commercially deployed in several countries, the key ingredients of Massive MIMO have made it into the 5G standard, the signal processing methods required to achieve unprecedented spectral efficiency have been developed, and the limitation due to pilot contamination has been resolved. Even the development of fully digital Massive MIMO arrays for mmWave frequencies - once viewed prohibitively complicated and costly - is well underway. In a few years, Massive MIMO with fully digital transceivers will be a mainstream feature at both sub-6 GHz and mmWave frequencies. In this paper, we explain how the first chapter of the Massive MIMO research saga has come to an end, while the story has just begun. The coming wide-scale deployment of BSs with massive antenna arrays opens the door to a brand new world where spatial processing capabilities are omnipresent. In addition to mobile broadband services, the antennas can be used for other communication applications, such as low-power machine-type or ultra-reliable communications, as well as non-communication applications such as radar, sensing and positioning. We outline five new Massive MIMO related research directions: Extremely large aperture arrays, Holographic Massive MIMO, Six-dimensional positioning, Large-scale MIMO radar, and Intelligent Massive MIMO.Comment: 20 pages, 9 figures, submitted to Digital Signal Processin

Survey on Mobile WiMAX- Technical Overview

Worldwide Interoperability for Microwave Access (WiMAX), is a wireless communications technology aiming to provide wireless data over long distances in a variety of ways as an alternative to cable and DSL, from point-to-point links to full mobile cellular type access. It is based on the IEEE 802.16 standard.  The goal of this deliverable is to provide an overview of the functionality and a description of the WiMAX network architecture. We also evaluate the special features of the WiMAX technology, such as the improved coverage in Non Line Of Sight (NLOS) environments, in order to examine the applicability of well-known localization techniques. Some of the advanced features such as adaptive antenna systems (AAS) which can significantly improve the performance are discussed. The performance will enable transparency of quality of service (QoS) between Mobile WiMAX and broadband wired services such as Cable and DSL. The scalable architecture, high data throughput and low cost deployment make Mobile WiMAX a leading solution for wireless broadband services. Due to “friendly ecosystem†hundreds of companies have contributed to the development of the technology. Finally, we investigate the characteristics of WiMAX technology

A survey of self organisation in future cellular networks

This article surveys the literature over the period of the last decade on the emerging field of self organisation as applied to wireless cellular communication networks. Self organisation has been extensively studied and applied in adhoc networks, wireless sensor networks and autonomic computer networks; however in the context of wireless cellular networks, this is the first attempt to put in perspective the various efforts in form of a tutorial/survey. We provide a comprehensive survey of the existing literature, projects and standards in self organising cellular networks. Additionally, we also aim to present a clear understanding of this active research area, identifying a clear taxonomy and guidelines for design of self organising mechanisms. We compare strength and weakness of existing solutions and highlight the key research areas for further development. This paper serves as a guide and a starting point for anyone willing to delve into research on self organisation in wireless cellular communication networks

The Case for Combining a Large Low-Band Very High Frequency Transmitter With Multiple Receiving Arrays for Geospace Research: A Geospace Radar

We argue that combining a high‐power, large‐aperture radar transmitter with several large‐aperture receiving arrays to make a geospace radar—a radar capable of probing near‐Earth space from the upper troposphere through to the solar corona—would transform geospace research. We review the emergence of incoherent scatter radar in the 1960s as an agent that unified early, pioneering research in geospace in a common theoretical, experimental, and instrumental framework, and we suggest that a geospace radar would have a similar effect on future developments in space weather research. We then discuss recent developments in radio‐array technology that could be exploited in the development of a geospace radar with new or substantially improved capabilities compared to the radars in use presently. A number of applications for a geospace radar with the new and improved capabilities are reviewed including studies of meteor echoes, mesospheric and stratospheric turbulence, ionospheric flows, plasmaspheric and ionospheric irregularities, and reflection from the solar corona and coronal mass ejections. We conclude with a summary of technical requirements

Massive MIMO is a reality - What is next? Five promising research directions for antenna arrays

Massive MIMO (multiple-input multiple-output) is no longer a “wild” or “promising” concept for future cellular networks—in 2018 it became a reality. Base stations (BSs) with 64 fully digital transceiver chains were commercially deployed in several countries, the key ingredients of Massive MIMO have made it into the 5G standard, the signal processing methods required to achieve unprecedented spectral efficiency have been developed, and the limitation due to pilot contamination has been resolved. Even the development of fully digital Massive MIMO arrays for mmWave frequencies—once viewed prohibitively complicated and costly—is well underway. In a few years, Massive MIMO with fully digital transceivers will be a mainstream feature at both sub-6 GHz and mmWave frequencies. In this paper, we explain how the first chapter of the Massive MIMO research saga has come to an end, while the story has just begun. The coming wide-scale deployment of BSs with massive antenna arrays opens the door to a brand new world where spatial processing capabilities are omnipresent. In addition to mobile broadband services, the antennas can be used for other communication applications, such as low-power machine-type or ultra-reliable communications, as well as non-communication applications such as radar, sensing and positioning. We outline five new Massive MIMO related research directions: Extremely large aperture arrays, Holographic Massive MIMO, Six-dimensional positioning, Large-scale MIMO radar, and Intelligent Massive MIMO

Economically sustainable public security and emergency network exploiting a broadband communications satellite

The research contributes to work in Rapid Deployment of a National Public Security and Emergency Communications Network using Communication Satellite Broadband. Although studies in Public Security Communication networks have examined the use of communications satellite as an integral part of the Communication Infrastructure, there has not been an in-depth design analysis of an optimized regional broadband-based communication satellite in relation to the envisaged service coverage area, with little or no terrestrial last-mile telecommunications infrastructure for delivery of satellite solutions, applications and services. As such, the research provides a case study of a Nigerian Public Safety Security Communications Pilot project deployed in regions of the African continent with inadequate terrestrial last mile infrastructure and thus requiring a robust regional Communications Satellite complemented with variants of terrestrial wireless technologies to bridge the digital hiatus as a short and medium term measure apart from other strategic needs. The research not only addresses the pivotal role of a secured integrated communications Public safety network for security agencies and emergency service organizations with its potential to foster efficient information symmetry amongst their operations including during emergency and crisis management in a timely manner but demonstrates a working model of how analogue spectrum meant for Push-to-Talk (PTT) services can be re-farmed and digitalized as a “dedicated” broadband-based public communications system. The network’s sustainability can be secured by using excess capacity for the strategic commercial telecommunication needs of the state and its citizens. Utilization of scarce spectrum has been deployed for Nigeria’s Cashless policy pilot project for financial and digital inclusion. This effectively drives the universal access goals, without exclusivity, in a continent, which still remains the least wired in the world

Customer premise service study for 30/20 GHz satellite system

Satellite systems in which the space segment operates in the 30/20 GHz frequency band are defined and compared as to their potential for providing various types of communications services to customer premises and the economic and technical feasibility of doing so. Technical tasks performed include: market postulation, definition of the ground segment, definition of the space segment, definition of the integrated satellite system, service costs for satellite systems, sensitivity analysis, and critical technology. Based on an analysis of market data, a sufficiently large market for services is projected so as to make the system economically viable. A large market, and hence a high capacity satellite system, is found to be necessary to minimize service costs, i.e., economy of scale is found to hold. The wide bandwidth expected to be available in the 30/20 GHz band, along with frequency reuse which further increases the effective system bandwidth, makes possible the high capacity system. Extensive ground networking is required in most systems to both connect users into the system and to interconnect Earth stations to provide spatial diversity. Earth station spatial diversity is found to be a cost effective means of compensating the large fading encountered in the 30/20 GHz operating band

Method for Real-Time Signal Selection for Passive Coherent Location Systems

Passive coherent location (PCL) systems use signals of opportunity to perform traditional radar detection, targeting, and tracking functions. Traditionally these signals include FM radio, digital TV, GSM, and GPS because of their availability in most urban environments. A benefit of having an abundance of signals is the ability to choose which of those best meet the desired system intentions. For example, one may want to choose a digital TV signal over an FM radio signal due to its range resolution characteristics. This work presents a novel algorithm for characterizing commercial signals for use in a PCL system. By analyzing each signal\u27s ambiguity function in terms of amplitude, transmitter geometry, range and Doppler resolution, and sidelobe levels, a comparative evaluation can be made to decide which signals are best suited for an intended radar function. In addition, this research shows that multiple signals can be combined in the detection process to increase the probability of detection over that of a single signal. Finally, this research investigates the geometric considerations for PCL systems in terms of bistatic radar geometry. The results show zones of linear and non-linear relationships between time delay, range, and Doppler frequency