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Introduction to Mobile Communication Systems

This reference provides an overview of the evolution, concepts, and systems of mobile communication, including cellular systems, cordless telephones, wireless access, and satellite systems.

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Introduction to Mobile Communication Systems

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  1. 移动通信原理 Reference: Theodore S. Rappaport, Wireless CommunicationsPrinciples and Practice, Second Edition http://home.ustc.edu.cn/~jzhang17/ 中国科学技术大学 个人通信与扩频实验室 邱玲 2015，3，2

  2. Contents 1. Introduction 2. Modern Wireless Systems 3. Cellular Concept 4. Mobile Radio Propagation: Large-Scale Path Loss 5. Mobile Radio Propagation: Small-Scale fading and multipath 6. Mobile Modulation Techniques 7. Equalization, Diversity, and channel coding 8. Speech coding 9. Multiple Access Techniques 10. Wireless Networking 11. Wireless Systems and Standards

  3. Chapter 1 Introduction

  4. Contents 1.1 Evolution of Wireless Communication 1.2 Wireless Communication Systems 1.2.1 Cellular Systems 1.2.2 Cordless Telephone 1.2.3 Wireless Access (WLL & W-LAN) 1.2.4 Satellite Systems 1.3 Concept of Mobile System 1.3.1 Basic Concept 1.3.2 Call Process

  5. 1.1 Evolution of Wireless Communication Evolution of Mobile Radio Communications 1897年马可尼发明无线电 • 上世纪二十年代至四十年代初期：移动通信的早期发展阶段 1921年美国底特律警察移动通信系统，1926年西德列车移动电话系统 • 上世纪四十年代中期至六十年代初期：公用移动通信业务开始问世 1946年美国贝尔“城市系统”，1950（西德）、1956（法国）、1959（英国），50年代中期，美国贝尔系统完成了人工交换系统 • 上世纪六十年代中期至七十年代中期：移动电话系统的改进和完善阶段 美国的IMTS和西德的B网路：直接拨号、自动选择无线频道并自动接入公用电话网 • 上世纪七十年代中期以后：无线通信开始进入新时代 用于无线通信的高可靠、小型化的晶体射频硬件的出现，无线设备朝小型化和功能多样化方面发展；另一方面，开始了公用移动通信系统新体制的论证与实验

  6. A little bit of wireless history • Maxwell’s Equation published in 1865

  7. A solution to the Maxwell’s Equation It predicted the existence of electromagnetic wave!

  8. All in the family!

  9. Experiments of Hertz • Hertz’s experiment to generate microwave in 1888 • Validated Maxwell’s prediction

  10. Experiments of Hertz

  11. Experiments of Hertz (cont.) • A simple schematic • Feasibility of microwave communication demonstrated

  12. The Big Step Forward from Marconi • Transmitted telegraph signals in 1890 at his home • Wireless telegraph between ships and shore in 1897 • Trans-Atlantic communication in Dec 14, 1901 from Poldhu, Cornwall (UK) to St John’s, Newfoundland, • (Is the earth round?) From www.footprintsshoes.com/marconi/marconi.htm

  13. The Big Step Forward from Marconi (cont.) • The letter “S” (Morse code …) was transmitted from a 25,000 W station • Jan 18, 1903, wireless telegram and a reply LONDONENGLAND IN TAKING ADVANTAGE OF THE WONDERFUL TRIUMPH OF SCIENTIFIC RESEARCH AND INGENUITY WHICH HAS BEEN ACHIEVED IN PERFECTING A SYSTEM OF WIRELESS TELEGRAPHY I EXTEND ON BEHALF OF THE AMERICAN MOST CORDIAL GREETINGS AND GOOD WISHES TO YOU AND TO ALL THE PEOPLE OF THE BRITISH EMPIRE THEODORE ROOSEVELT WELLFLEET MASS JAN 18 1903

  14. 1.2 Wireless Communication Systems • Cellular Systems • Cordless Telephone • Wireless Access Systems • Paging System • Satellite Systems

  15. 1.2.1 Cellular Systems

  16. First generation mobile communication --- 1G Analog System basic technical feature: analog technology analog circuit units Cellular structure, roaming, handover Second generation mobile communication --- 2G Digital system basic technical feature: digital technology digital process units SIM card, light handset, high capacity Third generation mobile communication --- 3G Smart system basic technical feature: intelligent process technology smart process units Multimedia, higher capacity, intelligent network

  17. 4G LTE-Release8/9: OFDM, MIMO, with a total of 32 million users • (August 2012) and expectations of close to two billion users in 2018. • LTE-A-Release10, finalized in 2010, the possibility for transmission • bandwidth beyond 20 MHz carrier aggregation, enhanced multi-antenna transmission, and the introduction of relaying functionality. • R11 Dec. 2012, In addition to further refining some of the features introduced as part of Rel-10, CoMP, enhanced support for heterogeneous deployments, advanced terminal receivers and for multistandard base stations supporting. • R12 June-Sept. 2014, not only increased capacity and enhanced end-user experience, Enhanced local area access, Multi-antenna enhancements, Improved support for machine-type communication • (MTC), Direct device-to-device communication • 5G:系统数据业务支撑能力达10Gbps，频谱及功率效率较4G提升10倍，网络覆盖的单位面积吞吐率较4G提升25倍。

  18. 1.2.2 Cordless Telephone

  19. 1.2.3 Wireless Access Systems---- Wireless Local Loop S-CDMA PHS IEEE 802.XX

  20. 1.2.4 Paging Systems

  21. To provide ultra-reliable coverage • Paging transmitters are located on tall buildings • Small RF bandwidths (to which the noise level is proportional) are used to maximize SNR of each paging receiver • Low data rates are used(6400bps)

  22. 1.2.5 Satellite Systems • Properties • Seamless coverage • Large coverage area • Long distance • Reliable communication link • Large bandwidth • Large capacity • Disadventages • Large delay (270ms，100ms)

  23. System composing • Space part • Ground part • terminal • Types • Synchronous • Asynchronous: middle orbit, ellipse orbit, low orbit • Applications • Navigation (Position, transportation…) • Digital film • Satellite radio, Satellite remote sensing

  24. 1.3 Concept of Mobile Systems 1.3.1 Basic Concept 1.3.2 Call Processing

  25. 1.3.1 Basic Concept • Cellular Structure

  26. Simplex • Multiple access • MS – BS – BSC – MSC • Link • Roaming, Handover

  27. Some Definitions

  28. 1.3.2 Call Process • How a Cellular Telephone Call is Made

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