Millimeter-Wave Cellular Wireless Networks: Potentials and Challenges
05 Feb 2014-Vol. 102, Iss: 3, pp 366-385
TL;DR: Measurements and capacity studies are surveyed to assess mmW technology with a focus on small cell deployments in urban environments and it is shown that mmW systems can offer more than an order of magnitude increase in capacity over current state-of-the-art 4G cellular networks at current cell densities.
Abstract: Millimeter-wave (mmW) frequencies between 30 and 300 GHz are a new frontier for cellular communication that offers the promise of orders of magnitude greater bandwidths combined with further gains via beamforming and spatial multiplexing from multielement antenna arrays. This paper surveys measurements and capacity studies to assess this technology with a focus on small cell deployments in urban environments. The conclusions are extremely encouraging; measurements in New York City at 28 and 73 GHz demonstrate that, even in an urban canyon environment, significant non-line-of-sight (NLOS) outdoor, street-level coverage is possible up to approximately 200 m from a potential low-power microcell or picocell base station. In addition, based on statistical channel models from these measurements, it is shown that mmW systems can offer more than an order of magnitude increase in capacity over current state-of-the-art 4G cellular networks at current cell densities. Cellular systems, however, will need to be significantly redesigned to fully achieve these gains. Specifically, the requirement of highly directional and adaptive transmissions, directional isolation between links, and significant possibilities of outage have strong implications on multiple access, channel structure, synchronization, and receiver design. To address these challenges, the paper discusses how various technologies including adaptive beamforming, multihop relaying, heterogeneous network architectures, and carrier aggregation can be leveraged in the mmW context.
Citations
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01 Sep 2017
TL;DR: It is found that the number of estimated MPCs in azimuth domain decreases obviously as the rotating step rises, which further affects PAS and ASA, which is closest to the reference value of 3GPP TR 38.900.
Abstract: The millimeter-wave communication is a key component in future broadband cellular networks. In this paper,a virtual multi-antenna measurement was conducted in an indoor line-of-sight scenario using a broadband channel sounder with 400 MHz bandwidth at 28 GHz. In the measurement,with an omni- directional antenna located in a fixed position at transmitter, horn antenna at receiver is rotated 360° in azimuth with the step of 2°, 3°, 5°, 8° and 10°, respectively. Then, the space- alternating generalized expectation-maximization (SAGE) algorithm was utilized to extract channel parameters from the measured results, including number of multipath components (MPCs) in azimuth domain, power azimuth spectrum (PAS) and root mean square azimuth spread of arrival angles (ASA). Finally, we compare these estimated parameters. This work aims to reveal the effects of the rotating step on the estimated results using SAGE algorithm in the virtual multi- antenna measurement. It is found that the number of estimated MPCs in azimuth domain decreases obviously as the rotating step rises, which further affects PAS and ASA. When with the step of 5°, the estimated ASA value is closest to the reference value of 3GPP TR 38.900.
2 citations
Cites background from "Millimeter-Wave Cellular Wireless N..."
...Nowadays, there has been rapidly growing interest in millimeter-wave (mmWave) bands where enormous bandwidths are available and much higher data rates can be supported [1]....
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Patent•
09 Nov 2018
TL;DR: In this article, a system for enabling signal penetration into a building comprises first circuitry, located on an outside of the building, for receiving RF signals and converting the RF signals into a format that overcomes losses caused by penetrating a structure of a building over a wireless communications link.
Abstract: A system for enabling signal penetration into a building comprises first circuitry, located on an outside of the building, for receiving RF signals and converting the RF signals into a format that overcomes losses caused by penetrating a structure of the building over a wireless communications link. The first circuitry further comprises a first transceiver dongle including a signal processing chipset for converting the received RF signals to the format that overcomes the losses occurring when the signals penetrate the structure of the building. Second circuitry, located on the interior of the building, receives the signals in the format that overcomes the losses caused by penetrating the structure of the building over the wireless communications link and converts the signals to a second format for transmission to the wireless devices within the building. The second circuitry further comprises a second transceiver dongle including the signal processing chipset for converting the received signals in the format that overcomes the losses caused by penetrating into the interior of the building into the second format.
2 citations
TL;DR: The capacity of a Gaussian MIMO channel in which the antenna outputs are processed by an analog linear combiner and then quantized by a set of zero threshold ADCs is studied and a new capacity upper bound for the zero threshold case is established that is tighter than the bounds available in the literature.
Abstract: The use of 1-bit analog-to-digital converters (ADCs) is seen as a promising approach to significantly reduce the power consumption and hardware cost of multiple-input multiple-output (MIMO) receivers. However, the nonlinear distortion due to 1-bit quantization fundamentally changes the optimal communication strategy and also imposes a capacity penalty to the system. In this paper, the capacity of a Gaussian MIMO channel in which the antenna outputs are processed by an analog linear combiner and then quantized by a set of zero threshold ADCs is studied. A new capacity upper bound for the zero threshold case is established that is tighter than the bounds available in the literature. In addition, we propose an achievability scheme which configures the analog combiner to create parallel Gaussian channels with phase quantization at the output. Under this class of analog combiners, an algorithm is presented that identifies the analog combiner and input distribution that maximize the achievable rate. Numerical results are provided showing that the rate of the achievability scheme is tight in the low signal-to-noise ratio (SNR) regime. Finally, a new 1-bit MIMO receiver architecture which employs analog temporal and spatial processing is proposed. The proposed receiver attains the capacity in the high SNR regime.
2 citations
01 Sep 2019
TL;DR: Simulation results show that channel estimate errors strongly depend on the interference power and the number of interfering BSs, and the proposed techniques are shown to achieve channel estimates comparable to interference-free systems.
Abstract: Millimeter wave (mmWave) systems rely on accurate channel state information (CSI) for the design of the precoding and combining matrices. Acquiring accurate CSI, however, is challenging due to the large number of antennas, the low signal-to-noise (SNR) ratio before beamforming, and possible interference from neighboring base stations (BSs). Prior work on channel estimation focused on the first two challenges and did not address inter- cell interference. Interference from neighboring BSs deteriorates the already low SNR and introduces errors in the channel estimate. This leads to additional interference in the system. This paper studies the effects of inter- cell interference on compressed sensing (CS) mmWave channel estimation techniques. A CS measurement matrix design is then proposed to jointly estimate the mmWave channel and null interference from neighboring BSs. Simulation results show that channel estimate errors strongly depend on the interference power and the number of interfering BSs. Moreover, in the presence of interference, the proposed techniques are shown to achieve channel estimates comparable to interference-free systems.
2 citations
Cites background from "Millimeter-Wave Cellular Wireless N..."
...Communication in the millimeter wave (mmWave) spectrum is one solution to meet the increasing demands of future cellular systems [1],[2]....
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TL;DR: In this paper , a planar gap waveguide Magic-Tee is designed to obtain 00 and 1800 phase states, and then integrated with an 8×8 slot antenna array to achieve multibeam operation for the first time.
Abstract: In this paper, a compact 94 GHz multibeam antenna array based on the binary phase-controlled concept is proposed. The feeding network is composed of four unconnected layers, and the ridge or groove-gap waveguides are adopted as the guided wave structures. A key planar gap waveguide Magic-Tee is designed to obtain 00 and 1800 phase states, and then integrates with an 8×8 slot antenna array to achieve multibeam operation for the first time. Compared with the traditional phased array and passive beamforming networks (BFN), the feeding design is simple in construction, consisting of only Magic-tees and cascaded power dividers without any phase shifters. Benefiting from the gap waveguide technology, the antenna array does not require electrical contact among the metal layers, so it is simple and low-cost to manufacture. The 8 × 8 slot antenna array can easily switch among one-beam and three different dual-beam states which point to ±70, ±170, and ±380, respectively. The measurement results of 6.6% bandwidth from 91.7 GHz to 98 GHz for both reflection coefficients < -10 dB and isolations > 25 dB are achieved. The proposed multibeam antenna array would be an attractive candidate for millimeter-wave multi-user communication where requires multiple beams simultaneously.
2 citations
References
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Book•
15 Jan 1996
TL;DR: WireWireless Communications: Principles and Practice, Second Edition is the definitive modern text for wireless communications technology and system design as discussed by the authors, which covers the fundamental issues impacting all wireless networks and reviews virtually every important new wireless standard and technological development, offering especially comprehensive coverage of the 3G systems and wireless local area networks (WLANs).
Abstract: From the Publisher:
The indispensable guide to wireless communicationsnow fully revised and updated!
Wireless Communications: Principles and Practice, Second Edition is the definitive modern text for wireless communications technology and system design. Building on his classic first edition, Theodore S. Rappaport covers the fundamental issues impacting all wireless networks and reviews virtually every important new wireless standard and technological development, offering especially comprehensive coverage of the 3G systems and wireless local area networks (WLANs) that will transform communications in the coming years. Rappaport illustrates each key concept with practical examples, thoroughly explained and solved step by step.
Coverage includes:
An overview of key wireless technologies: voice, data, cordless, paging, fixed and mobile broadband wireless systems, and beyond
Wireless system design fundamentals: channel assignment, handoffs, trunking efficiency, interference, frequency reuse, capacity planning, large-scale fading, and more
Path loss, small-scale fading, multipath, reflection, diffraction, scattering, shadowing, spatial-temporal channel modeling, and microcell/indoor propagation
Modulation, equalization, diversity, channel coding, and speech coding
New wireless LAN technologies: IEEE 802.11a/b, HIPERLAN, BRAN, and other alternatives
New 3G air interface standards, including W-CDMA, cdma2000, GPRS, UMTS, and EDGE
Bluetooth wearable computers, fixed wireless and Local Multipoint Distribution Service (LMDS), and other advanced technologies
Updated glossary of abbreviations and acronyms, and a thorolist of references
Dozens of new examples and end-of-chapter problems
Whether you're a communications/network professional, manager, researcher, or student, Wireless Communications: Principles and Practice, Second Edition gives you an in-depth understanding of the state of the art in wireless technologytoday's and tomorrow's.
17,102 citations
"Millimeter-Wave Cellular Wireless N..." refers background in this paper
...Also, the human body and many outdoor materials being very reflective, allow them to be important scatterers for mmW propagation [28], [30]....
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...However, these measurements were performed in an outdoor campus setting with much lower building density and greater opportunities for LOS connectivity than would be found in a typical urban deployment....
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...Despite the potential of mmW cellular systems, there are a number of key challenges to realizing the vision of cellular networks in these bands: • Range and directional communication: Friis’ transmis- sion law [54] states that the free space omnidirectional path loss grows with the square of the…...
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TL;DR: The motivation for new mm-wave cellular systems, methodology, and hardware for measurements are presented and a variety of measurement results are offered that show 28 and 38 GHz frequencies can be used when employing steerable directional antennas at base stations and mobile devices.
Abstract: The global bandwidth shortage facing wireless carriers has motivated the exploration of the underutilized millimeter wave (mm-wave) frequency spectrum for future broadband cellular communication networks. There is, however, little knowledge about cellular mm-wave propagation in densely populated indoor and outdoor environments. Obtaining this information is vital for the design and operation of future fifth generation cellular networks that use the mm-wave spectrum. In this paper, we present the motivation for new mm-wave cellular systems, methodology, and hardware for measurements and offer a variety of measurement results that show 28 and 38 GHz frequencies can be used when employing steerable directional antennas at base stations and mobile devices.
6,708 citations
"Millimeter-Wave Cellular Wireless N..." refers background or methods in this paper
...In both 28- and 73-GHz measurements, each point was classified as either being in a NLOS or LOS situation, based on a manual classification made at the time of the measurements; see [26] and [28]–[33]....
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...• Empirical NYC: These curves are based on the omnidirectional path loss predicted by our linear model (1) for the mmW channel with the parameters from Table 1, as derived from the directional measurements in [26]....
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...Details of the measurements can be found in [26], [28]– [33], [81]....
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...This tremendous potential has led to considerable recent interest in mmW cellular both in industry [7]–[9], [18], [19] and academia [20]–[26], with a growing belief that mmW bands will play a significant role in beyond 4G and 5G cellular systems [27]....
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...In particular, we survey our own measurements [26], [28]–[33] made in New York City (NYC) in both 28- and 73-GHz bands and the statistical models for the channels developed in [34]....
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TL;DR: The gains in multiuser systems are even more impressive, because such systems offer the possibility to transmit simultaneously to several users and the flexibility to select what users to schedule for reception at any given point in time.
Abstract: Multiple-input multiple-output (MIMO) technology is maturing and is being incorporated into emerging wireless broadband standards like long-term evolution (LTE) [1]. For example, the LTE standard allows for up to eight antenna ports at the base station. Basically, the more antennas the transmitter/receiver is equipped with, and the more degrees of freedom that the propagation channel can provide, the better the performance in terms of data rate or link reliability. More precisely, on a quasi static channel where a code word spans across only one time and frequency coherence interval, the reliability of a point-to-point MIMO link scales according to Prob(link outage) ` SNR-ntnr where nt and nr are the numbers of transmit and receive antennas, respectively, and signal-to-noise ratio is denoted by SNR. On a channel that varies rapidly as a function of time and frequency, and where circumstances permit coding across many channel coherence intervals, the achievable rate scales as min(nt, nr) log(1 + SNR). The gains in multiuser systems are even more impressive, because such systems offer the possibility to transmit simultaneously to several users and the flexibility to select what users to schedule for reception at any given point in time [2].
5,158 citations
"Millimeter-Wave Cellular Wireless N..." refers background in this paper
...These multiple antenna systems can be used to form very high gain, electrically steerable arrays, fabricated at the base station (BS), in the skin of a cellphone, or even within a chip [6], [10]–[17]....
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TL;DR: In this article, the authors describe five technologies that could lead to both architectural and component disruptive design changes: device-centric architectures, millimeter wave, massive MIMO, smarter devices, and native support for machine-to-machine communications.
Abstract: New research directions will lead to fundamental changes in the design of future fifth generation (5G) cellular networks. This article describes five technologies that could lead to both architectural and component disruptive design changes: device-centric architectures, millimeter wave, massive MIMO, smarter devices, and native support for machine-to-machine communications. The key ideas for each technology are described, along with their potential impact on 5G and the research challenges that remain.
3,711 citations
TL;DR: The technical and business arguments for femtocells are overview and the state of the art on each front is described and the technical challenges facing femtocell networks are described and some preliminary ideas for how to overcome them are given.
Abstract: The surest way to increase the system capacity of a wireless link is by getting the transmitter and receiver closer to each other, which creates the dual benefits of higher-quality links and more spatial reuse. In a network with nomadic users, this inevitably involves deploying more infrastructure, typically in the form of microcells, hot spots, distributed antennas, or relays. A less expensive alternative is the recent concept of femtocells - also called home base stations - which are data access points installed by home users to get better indoor voice and data coverage. In this article we overview the technical and business arguments for femtocells and describe the state of the art on each front. We also describe the technical challenges facing femtocell networks and give some preliminary ideas for how to overcome them.
3,298 citations
"Millimeter-Wave Cellular Wireless N..." refers background in this paper
...Heterogeneous networks, or HetNets, have been one of the most active research areas in cellular standards bodies in the last five years [45], [48], [67], [68], with the main focus being intercell interference coordination and load balancing....
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