5G无线通信网络中英文对照外文翻译文献

5G无线通信网络中英文对照外文翻译文献

(文档含英文原文和中文翻译)

5G无线通信网络中英文对照外文翻译文献

翻译：

5G无线通信网络的蜂窝结构和关键技术

摘要

第四代无线通信系统已经或者即将在许多国家部署。然而，随着无线移动设备和服务的激增，仍然有一些挑战尤其是4G所不能容纳的，例如像频谱危机和高能量消耗。无线系统设计师们面临着满足新型无线应用对高数据速率和机动性要求的持续性增长的需求，因此他们已经开始研究被期望于2020年后就能部署的第五代无线系统。在这篇文章里面，我们提出一个有内门和外门情景之分的潜在的蜂窝结构，并且讨论了多种可行性关于5G无线通信系统的技术，比如大量的MIMO技术，节能通信，认知的广播网络和可见光通信。面临潜在技术的未知挑战也被讨论了。

介绍

信息通信技术（ICT）创新合理的使用对世界经济的提高变得越来越重要。无线通信网络在全球ICT战略中也许是最挑剔的元素，并且支撑着很多其他的行业，它是世界上成长最快最有活力的行业之一。欧洲移动天文台（EMO）报道2010年移动通信业总计税收1740亿欧元,从而超过了航空航天业和制药业。无线技术的发展大大提高了人们在商业运作和社交功能方面通信和生活的能力无线移动通信的显著成就表现在技术创新的快速步伐。从1991年二代移动通信系统(2G)的初次登场到2001年三代系统（3G）的首次起飞，无线移动网络已经实现了从一个纯粹的技术系统到一个能承载大量多媒体内容网络的转变。4G无线系统被设计出来用来满足IMT-A技术使用IP面向所有服务的需求。在4G系统中，先进的无线接口被用于正交频分复用技术（OFDM），多输入多输出系统（MIMO）和链路自适应技术。4G无线网络可支持数据速率可达1Gb/s的低流度，比如流动局域无线访问，还有速率高达100M/s的高流速，例如像移动访问。LTE系统和它的延伸系统LTE-A，作为实用的4G系统已经在全球于最近期或不久的将来部署。

然而，每年仍然有戏剧性增长数量的用户支持移动宽频带系统。越来越多的

5G无线通信网络中英文对照外文翻译文献

人渴望更快的网络访问速度，时髦的手机，总的来说就是更快地与他人通信或信息访问。如今更多功能强大小巧的手机和便捷电脑可以满足先进的多媒体功能变得越来越受欢迎。这就造成了无线移动设备和服务的激增。EMO指出自从2006年起，移动宽频每年有92%的增长。无线世界研究论坛（WWRF）预言到2017年会有七万亿的无线设备来服务七十亿的人口；也就是说无线网络连接设备的数量将会是世界人口数量的1000倍。随着越来越多的设备无线化许多研究难题需要被解决。

最重要的难题之一就是蜂窝通信中射频光谱分配的物质缺乏。蜂窝频率把极高频带用于蜂窝手机，一般来讲范围可从几百兆赫兹到几千兆赫兹。这些频谱被严重的使用以至于对操作员更多的获取造成困难。另一个难题就是先进无线技术的部署面临高能量消耗的费用。无线通信系统中高能消耗的增长间接造成了二氧化碳排放量的增长，后者被视为当前生态环境的主要威胁。此外，据手机运营商反映基站的能源消耗贡献了超过70%的电力账单。事实上，节能通信并不是4G无线系统中的最初需求之一，但是它在之后的舞台上被作为问题所提及。其他的难题，例如平均频谱效率、高传输率和高迁移率、无缝覆盖、多样化的服务质量请求以及分散的用户体验（不同无线设备/接口的不兼容和异构网络），仅仅提及一点点。

以上所有问题正给手机服务提供商带来更多压力，他们正面临着有更高传输率、更大的网络容量、更高的频谱效率、更高的能源利用率和更高的利用率规定的新型无线应用的持续增长需求。另一方面，在当前的技术条件下，4G网络在传输率方面几乎已经达到了理论上的限制，因此并不能充分的解决以上难题。从这层意义上来说，我们需要开创性的无线技术来解决以上由数万亿无线设备造成的问题，并且研究员们已经着手研究超4G（B4G）或者5G无线技术。中英科学桥工程：B4G无线移动通信(http://www.ukchinab4g. ac.uk/)可能是世界上着手B4G研究的首批项目之一，其中的一些潜在的B4G技术已经被确定了。欧洲和中国也已经开始了一些5G项目，比如由欧盟支持的

METIS

2020(https://www.metis2020. com/)和由中国科学院支持的在5G方面的国家863重点工程。诺基亚西门子通信公司描述通过对比2010年的通信水准今后十年潜在的无线接入技术可以被进一步开发用来支持多大超过一千倍的通信量。三星公

5G无线通信网络中英文对照外文翻译文献

司展示了一个运用微波技术使传输率在两千米的范围内超过1Gb/s的无线系统。

5G网络，预期大约在2020年被标准化，究竟是什么呢？由于现在太早以至于不能确切地定义。广泛的认同是与4G网络相比，5G网络应该达到1000倍的系统容量，10倍的频谱利用率、能源利用率和传输率（低流动性下最高传输率为10Gb/s，高流动性下最高传输率为1Gb/s）还有25倍平均系统吞吐量。5G网络的目标在于连接整个世界以及实现任何人之间（人与人），任何事物之间（人与机器，机器与机器）的无缝的、无处不在的通信，无论他们在哪，无论他们什么时候需要，也无论他们用什么电子设备/服务/网络。这就意味着5G网络应该能够支持一些4G网络所不能支持的特殊情况（例如乘坐高铁的用户）。高铁车速可轻松达到350到500km/h，然后4G网络所能支持通信的情况是250km/h。本篇文章中，我们提出了一个潜在的5G蜂窝结构并且讨论有希望的技术用来部署以便满足5G的需求。

这篇文章剩下的安排如下。我们提出了一个潜在的5G蜂窝结构。我们描述一些可行性的关键技术可以被5G系统采用。未来的挑战是显著的，最终我们会得出结论。

潜在的5G无线蜂窝结构

为了解决以上难题并且满足5G系统的需求，我们需要在蜂窝结构的设计上做个戏剧性的改变。我们知道无线用户80%的时间都是待在户内，待在户外的仅仅约有20%。当前常见的蜂窝结构通常是为移动用户在蜂窝通信中间建立一个露天基站，这样就不用管他们实在户内还是户外。对于户内用户与户外基站间的通信，信号不得不穿过建筑墙，造成很高的穿透损耗，从而显著损伤无线传输的传输速率、频谱利用率、能源利用率。

设计5G蜂窝结构的中心思想就是分开户内和户外的情况这样穿透损耗经过建筑墙后可以在某种意义上来说避免掉。这些将会由分布式天线系统（DAS）和大量的MIMO技术来实现,即在地面上部署由几十个或几百个天线单组成的分布式天线阵。然而目前最主流的MIMO系统使用两个或四个天线，大量使用MIMO系统的目的是为了开发尽可能大的容量效益以提升更大的天线阵。户外基站将会装备由一些天线单元（也有大阵列天线）组成的大阵列天线，这些大阵列天线分布在覆盖区周围，通过光纤连接基站，从而从DAS和大量的MIMO技术中都能

5G无线通信网络中英文对照外文翻译文献

受益。户外手机用户通常配备有限数量的天线单元，但是他们可以通过互相合作形成一个虚拟的大阵列天线，连同基站天线阵将会构造虚拟的大规模MIMO链接群。大阵列天线也将被安装在每个建筑的外面以便与户外基站群或者拥有分布式天线单元的基站群相互通信，与可见组件通信也是有可能的。大阵列天线用电缆连接到能与户内用户之间通信的建筑内部的无线接入点。这样必定会在短时间内提高基础设备的花费最终显著提升覆盖区平均生产力，频谱效率，能源效率还有蜂窝系统传输率。采用这样的蜂窝结构，户内用户仅需要使用安装在户外建筑的大阵列天线便可与户内无线接入点通信，很多的技术可以被利用以便适用高数据速率进行的短程通信。举一些例子包括WiFi，毫微微蜂窝，超宽频（UWB），毫米波通信（3——300GHz），还有可见光通信(VLC)（400——490THz）。值得说明的是毫米波和VLC技术使用更高的频率并不适用传统的蜂窝通信。这些高频波并不能很好地穿透固体材料并且很容易就会被气体，雨水还有植物吸收或分散。因此，很难将这些波用于户外和远距离应用。然而，随着宽频带的实现，毫米波和VLC技术可以大大提高在户内情况下的数据传输速率。为了解决频谱缺乏问题，并且找到新的不为传统无线服务（例如毫米波通信和VLC）所用的频带，我们可以尽力提高现有无线频谱的频谱利用率，比如取道认识的无线网络。

5G蜂窝结构同样应该是一种有宏蜂窝，微蜂窝，小基站和继电器组成的混杂结构。为了适应高机动性用户比如乘车和乘高铁的用户，我们已经提出了超小型移动基站的概念，即结合移动中继和超小型基站的概念。超小型移动基站位于车辆内部可以和位于车内的用户通信，而大阵列天线位于车辆外面和户外的基站通信。一个超小型移动基站和它关联的用户都被基站看作一个单元。从用户的角度来看，超小型移动基站被看作正式的基站。这和上面区分户内（车辆内部）和户外情况的观点非常相似。已经能表明的是用户使用超小型移动基站在享受高数据速率的服务的同时减少信令开销。以上提出的5G混杂蜂窝结构在图1阐明。

有前景的5G无线网络的关键技术

在这一部分，基于以上提出的混杂式蜂窝结构，我们讨论了一些有前景的无线网络关键技术使之能够满足5G无线网络的性能要求。发展这些技术的目的是通过有效利用所有可能的资源以适应戏剧性的容量增长。基于著名的香农定理，系统的总容量Csum可以近似的表示为

5G无线通信网络中英文对照外文翻译文献

Csum网路通道PBilog21i （1）

Np其中Bi是第i条信道的带宽，Pi是第i条信道的信号功率，Np表示噪声功率。从公式1可以看出系统总容量Csum等于所有子通道和网路容量之和。为了增加

Csum，我们可以提高网络覆盖范围（通过使用含有宏蜂窝，微蜂窝，小基站，继

电器，超小型移动基站的网络），子通道的数量（通过使用大量的MIMO技术，空间调整，协作式MIMO，DAS,管理干涉等等），带宽（通过CR网络，毫米波通信，VLC，多标准系统等等）还有功率（能源利用率和绿色通信）。在下文中，我们重点聚焦于一些关键技术。

5G无线通信网络中英文对照外文翻译文献

外文原文：

ABSTRACT

The fourth generation wireless communica- tion systems have been deployed or are soon to be deployed in many countries. However, with an explosion of wireless mobile devices and ser- vices, there are still some challenges that cannot be accommodated even by 4G, such as the spec- trum crisis and high energy consumption. Wire- less system designers have been facing the continuously increasing demand for high data rates and mobility required by new wireless applications and therefore have started research on fifth generation wireless systems that are expected to be deployed beyond 2020. In this article, we propose a potential cellular architec- ture that separates indoor and outdoor scenar- ios, and discuss various promising technologies for 5G wireless communication systems, such as massive MIMO, energy-efficient communica- tions, cognitive radio networks, and visible light

5G无线通信网络中英文对照外文翻译文献

communications. Future challenges facing these potential technologies are also discussed. INTRODUCTION

The innovative and effective use of information and communication technologies (ICT) is becoming increasingly important to improve the economy of the world [1]. Wireless communica- tion networks are perhaps the most critical ele- ment in the global ICT strategy, underpinning many other industries. It is one of the fastest growing and most dynamic sectors in the world. The European Mobile Observatory (EMO) reported that the mobile communication sector had total revenue of €174 billion in 2010, there- by bypassing the aerospace and pharmaceutical sectors [2]. The development of wireless tech- nologies has greatly improved people’s ability to communicate and live in both business opera- tions and social functions.

The phenomenal success of wireless mobile communications is mirrored by a rapid pace of technology innovation. From the second genera-

5G无线通信网络中英文对照外文翻译文献

tion (2G) mobile communication system debuted in 1991 to the 3G system first launched in 2001, the wireless mobile network has transformed from a pure telephony system to a network that can transport rich multimedia contents. The 4G wireless systems were designed to fulfill the requirements of International Mobile Telecom- munications-Advanced (IMT-A) using IP for all services [3]. In 4G systems, an advanced radio interface is used with orthogonal frequency-divi- sion multiplexing (OFDM), multiple-input multi- ple-output (MIMO), and link adaptation technologies. 4G wireless networks can support data rates of up to 1 Gb/s for low mobility, such as nomadic/local wireless access, and up to 100 Mb/s for high mobility, such as mobile access. Long-Term Evolution (LTE) and its extension, LTE-Advanced systems, as practical 4G systems, have recently been deployed or soon will be deployed around the globe.

However, there is still a dramatic increase in the number of users who subscribe to mobile

5G无线通信网络中英文对照外文翻译文献

broadband systems every year. More and morepeople crave faster Internet access on the move,

trendier mobiles, and, in general, instant com- munication with others or access to information. More powerful smartphones and laptops are becoming more popular nowadays, demanding advanced multimedia capabilities. This has resulted in an explosion of wireless mobile devices and services. The EMO pointed out that there has been a 92 percent growth in mobile broadband per year since 2006 [2]. It has been predicted by the Wireless World Research Forum (WWRF) that 7 trillion wireless devices will serve 7 billion people by 2017; that is, the number of network-connected wireless devices will reach 1000 times the world’s population [4]. As more and more devices go wireless, many research challenges need to be addressed. One of the most crucial challenges is the physical scarcity of radio frequency (RF) spectra allocated for cellular communications. Cellular frequencies use ultra-high-frequency bands for

5G无线通信网络中英文对照外文翻译文献

cellular phones, normally ranging from several hundred megahertz to several gigahertz. These frequency spectra have been used heavily, mak- ing it difficult for operators to acquire more. Another challenge is that the deployment of advanced wireless technologies comes at the cost of high energy consumption. The increase of energy consumption in wireless communication systems causes an increase of CO 2 emission indi- rectly, which currently is considered as a major threat for the environment. Moreover, it has been reported by cellular operators that the energy consumption of base stations (BSs) con- tributes to over 70 percent of their electricity bill [5]. In fact, energy-efficient communication was not one of the initial requirements in 4G wire- less systems, but it came up as an issue at a later stage. Other challenges are, for example, aver- age spectral efficiency, high data rate and high mobility, seamless coverage, diverse quality of service (QoS) requirements, and fragmented user experience (incompatibility of different

5G无线通信网络中英文对照外文翻译文献

wireless devices/interfaces and heterogeneous networks), to mention only a few. All the above issues are putting more pres- sure on cellular service providers, who are facing continuously increasing demand for higher data rates, larger network capacity, higher spectral efficiency, higher energy efficiency, and higher mobility required by new wireless applications. On the other hand, 4G networks have just about reached the theoretical limit on the data rate with current technologies and therefore are not sufficient to accommodate the above challenges. In this sense, we need groundbreaking wireless technologies to solve the above problems caused by trillions of wireless devices, and researchers have already started to investigate beyond 4G (B4G) or 5G wireless techniques. The project UK-China Science Bridges: (B)4G Wireless Mobile Communications (http://www.ukchinab4g. ac.uk/) is perhaps one of the first projects in the world to start B4G research, where some potential B4G technologies were identified. Europe and China

5G无线通信网络中英文对照外文翻译文献

have also initiated some 5G projects, such as METIS 2020 (https://www.metis2020. com/) sup- ported by EU and National 863 Key Project in 5G supported by the Ministry of Science and

Technology (MOST) in China. Nokia SiemensNetworks described how the underlying radio

access technologies can be developed further to support up to 1000 times higher traffic volumes compared to 2010 travel levels over the next 10 years [6]. Samsung demonstrated a wireless sys- tem using millimeter (mm) wave technologies with data rates faster than 1 Gb/s over 2 km [7]. What will the 5G network, which is expected to be standardized around 2020, look like? It is now too early to define this with any certainty. However, it is widely agreed that compared to the 4G network, the 5G network should achieve 1000 times the system capacity, 10 times the spectral efficiency, energy efficiency and data rate (i.e., peak data rate of 10 Gb/s for low mobility and peak data rate of 1 Gb/s for high mobility), and 25 times the average cell through-

5G无线通信网络中英文对照外文翻译文献

put. The aim is to connect the entire world, and achieve seamless and ubiquitous communica- tions between anybody (people to people), any- thing (people to machine, machine to machine), wherever they are (anywhere), whenever they need (anytime), by whatever electronic devices/services/networks they wish (anyhow). This means that 5G networks should be able to support communications for some special sce- narios not supported by 4G networks (e.g., for high-speed train users). High-speed trains can easily reach 350 up to 500 km/h, while 4G net- works can only support communication scenarios up to 250 km/h. In this article, we propose a potential 5G cellular architecture and discuss some promising technologies that can be deployed to deliver the 5G requirements. The remainder of this article is organized as follows. We propose a potential 5G cellular architecture. We describe some promising key technologies that can be adopted in the 5G sys- tem. Future challenges are highlighted. Finally,

5G无线通信网络中英文对照外文翻译文献

conclusions are drawn. A POTENTIAL 5G WIRELESS CELLULAR ARCHITECTURE

To address the above challenges and meet the 5G system requirements, we need a dramatic change in the design of cellular architecture. We know that wireless users stay indoors for about 80 percent of time, while only stay ourdoors about 20 percent of the time [8]. The current conventional cellular architecture normally uses an outdoor BS in the middle of a cell communi- cating with mobile users, no matter whether they stay indoors or outdoors. For indoor users com- municating with the outdoor BS, the signals have to go through building walls, and this causes very high penetration loss, which significantly dam- ages the data rate, spectral efficiency, and ener- gy efficiency of wireless transmissions. One of the key ideas of designing the 5G cel- lular architecture is to separate outdoor and indoor scenarios so that penetration loss through building walls can somehow be avoided. This will

5G无线通信网络中英文对照外文翻译文献

be assisted by distributed antenna system (DAS) and massive MIMO technology [9], where geo- graphically distributed antenna arrays with tens or hundreds of antenna elements are deployed. While most current MIMO systems utilize two

to four antennas, the goal of massive MIMO systems is to exploit the potentially large capacity

gains that would arise in larger arrays of anten- nas. Outdoor BSs will be equipped with large antenna arrays with some antenna elements (also large antenna arrays) distributed around the cell and connected to the BS via optical fibers, bene- fiting from both DAS and massive MIMO tech- nologies. Outdoor mobile users are normally equipped with limited numbers of antenna ele- ments, but they can collaborate with each other to form a virtual large antenna array, which together with BS antenna arrays will construct virtual massive MIMO links. Large antenna arrays will also be installed outside of every building to communicate with outdoor BSs or distributed antenna elements of BSs, possibly

5G无线通信网络中英文对照外文翻译文献

with line of sight (LoS) components. Large anten- na arrays have cables connected to the wireless access points inside the building communicating with indoor users. This will certainly increase the infrastructure cost in the short term while signifi- cantly improving the cell average throughput, spectral efficiency, energy efficiency, and data rate of the cellular system in the long run. Using such a cellular architecture, as indoor users only need to communicate with indoor wireless access points (not outdoor BSs) with large antenna arrays installed outside build- ings, many technologies can be utilized that are suitable for short-range communications with high data rates. Some examples include WiFi, femtocell, ultra wideband (UWB), mm-wave communications (3–300 GHz) [7], and visible light communications (VLC) (400–490 THz) [10]. It is worth mentioning that mm-wave and VLC technologies use higher frequencies not traditionally used for cellular communications. These high-frequency waves do not penetrate

5G无线通信网络中英文对照外文翻译文献

solid materials very well and can readily be absorbed or scattered by gases, rain, and foliage. Therefore, it is hard to use these waves for outdoor and long distance applications. However, with large bandwidths available, mm- wave and VLC technologies can greatly increase the transmission data rate for indoor scenarios. To solve the spectrum scarcity prob- lem, besides finding new spectrum not tradi- tionally used for wireless services (e.g., mm-wave communications and VLC), we can also try to improve the spectrum utilization of existing radio spectra, for example, via cogni- tive radio (CR) networks [11].

The 5G cellular architecture should also be a heterogeneous one, with macrocells, microcells, small cells, and relays. To accommodate high- mobility users such as users in vehicles and high- speed trains, we have proposed the mobile femtocell (MFemtocell) concept [12], which combines the concepts of mobile relay and fem- tocell. MFemtocells are located inside vehicles

5G无线通信网络中英文对照外文翻译文献

to communicate with users within the vehicle, while large antenna arrays are located outside the vehicle to communicate with outdoor BSs. An MFemtocell and its associated users are all viewed as a single unit to the BS. From the user point of view, an MFemtocell is seen as a regu- lar BS. This is very similar to the above idea of separating indoor (inside the vehicle) and out- door scenarios. It has been shown in [12] that users using MFemtocells can enjoy high-data-rate services with reduced signaling overhead. The above proposed 5G heterogeneous cellular architecture is illustrated in Fig. 1.

PROMISING KEY

5G WIRELESS TECHNOLOGIES

In this section, based on the above proposed heterogeneous cellular architecture, we discuss some promising key wireless technologies that can enable 5G wireless networks to fulfill perfor- mance requirements. The purpose of developing these technologies is to enable a dramatic capac- ity increase in the 5G network with efficient uti-

5G无线通信网络中英文对照外文翻译文献

lization of all possible resources. Based on the well-known Shannon theory, the total system capacity C sum can be approximately expressed by

Csum网路通道Pi (1) Bilog21Npwhere B i is the bandwidth of the ith channel, P i is the signal power of the ith channel, and N p denotes the noise power. From Eq. 1, it is clear that the total system capacity C sum is equivalent to the sum capacity of all subchannels and het- erogeneous networks. To increase C sum , we can increase the network coverage (via heteroge- neous networks with macrocells, microcells, small cells, relays, MFemtocell [12], etc.), num- ber of subchannels (via massive MIMO [9], spa- tial modulation [SM] [13], cooperative MIMO, DAS, interference management, etc.), bandwidth (via CR networks [11], mm-wave communica- tions, VLC [10], multi-standard systems, etc.), and power (energy-efficient or green communi- cations). In the following, we focus on some of the key technologies.