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Wireless CommunicationWireless Communication
ICRM & TRUs
ICP
MTX
輔仁大學 電子工程系所
林 昇 洲 博士
無線通訊
Wireless Communication
Lesson 1 –Introduction to wireless communication 1 Dr. Sheng-Chou Lin
Personal Profile學歷: Ph. D. — University of Texas at Arlington, Texas, USA.經歷:
電子工業研究所,數位積體電路設計部 - 助理工程師 中山科學院系統發展中心,飛彈模擬室,微波模擬組 - 助理工程師 北方貝爾研究室 Bell Northern Research (BNR) TX, USA - 短期研究生 北電網路 NORTEL Networks, TX, USA,無線網路系統部 - 資深工程師 輔仁大學電子工程系所 - 訪問助理教授
專長:
Wireless, Mobile Communications (無線,行動通訊系統) Radar System Design (雷達系統設計) Fiber Optics Communications(光纖通訊) Statistical Signal Processing (統計信號處理) Microwave Theory and Engineering (微波原理與工程) Semiconductor Devices and Manufacture (半導體元件及製程)
Page 2
Wireless Communication
Lesson 1 –Introduction to wireless communication 2 Dr. Sheng-Chou Lin
Course Objectives
Gain historical perspective of cellular origin
Recognize basic definitions and common terminology
Explain mechanics of cellular call processing
Describe the modulation schemes used in cellular andunderstand their basic performance characteristics
Recognize basic cellular and RF concepts
Understand basic system design and growth issues
Understand the trends and major business reasons forchoosing a technology
Give sufficient understanding of this technology to make aintelligent decision
Wireless Communication
Lesson 1 –Introduction to wireless communication 3 Dr. Sheng-Chou Lin
Router
IS
MTX
MTX
PSTN
Public Network
DMS-100PBX
DMS MTX
DMS MTX
ICPT1/E1
T1/E1
T1
ICRM
ICRM
ICRM
ICRM
ICRM
ICRM
T1
T1
T1ICP
inter-systemhandofftrunks
Wire Line
Wireless
Cell Sites
DID / IDIDtrunks
T1 T1T1 POTSline
card
DMS-200DMS-100
BRIPRI ISUP
ISUP
LPP
LPP
Router
Ethernet LAN
Networking &Data Traffic
Service Provider’sData Network
Other Service Provider
Internet ServiceProvider
ISTRU
IS
ISTRU
A cellular Network Architecture
Page 3
Wireless Communication
Lesson 1 –Introduction to wireless communication 4 Dr. Sheng-Chou Lin
Course Outline Introduction and Overview of Technology and Business
•Technology Overview•Business and Regulatory issues
Cellular concepts•Cellular/PCS Network Architecture•Cellular Design and Frequency Planning
Basic Cellular Call Processing•Origination, Termination, and Registration
Digital Communication Basics•Modulation Techniques and Access Methods
RF basic principles•Radio Propagation, Link Budgets, Fading and Coverage•Antenna Engineering, Traffic Engineering•Cell Site Engineering and Operational Issues
Wireless Communication
Lesson 1 –Introduction to wireless communication 5 Dr. Sheng-Chou Lin
Course Outline (Cont.)
Wireless Systems and Standards•Analog, and ITA/EIA-136 (TDMA)•Global System for Mobile Communications(GSM)•TIA/EIA-95 (CDMA)•Wireless Mobile Data•Third Generation Systems
Advanced Wireless technology•Wireless LAN•Blue Tooth Technology•Smart Antenna Systems, Space-time processing, MIMO•OFDM-CDMA, Wideband CDMA•Soft Radio
Presentations from Wireless Industry Project Presentations
Page 4
Wireless Communication
Lesson 1 –Introduction to wireless communication 6 Dr. Sheng-Chou Lin
Grading
Attendance (Not Mandatory) 10%•- 2M for the Mth absence•+ 2 for a good question
Midterm Exam 40%•2 hour, inclass/proctored•Close book, 2-page cheat sheet•Take-home again (10%)
Final Exam 50%•2 hour, inclass/proctored•Close book, 2-page cheat sheet•Take-home again (10%)
Office Hours• Tuesday: 2:00 ~4:00 pm at office (聖言樓SF726B)• Phone number: (02)29031111~3798, email:[email protected]
Wireless Communication
Lesson 1 –Introduction to wireless communication 7 Dr. Sheng-Chou Lin
Course Textbook
Theodore S. Rappaport “Wireless Communications, Principles and Practice, secondEdition”, Prentice Hall PTR
Reference Book• Joseph C. Liberti, JR., Theodore S. Rappaport, “Smart Antennas for wireless
communications, IS-95 and Third Beneration CDMA Applications”, Prentice Hall PTR.• William C.Y. Lee, “Mobile Communications Engineering”, McGraw-Hill• R. Vincent Poor, Gregory W. Wornell, “Wireless Communications, Signal,
Processing, Perspectives”, Prentice Hall PTR• David J. Goodman, “Wireless Persinal Communications Systems”. Addison-
Wesley.• Blake,”wireless communication Technology”, Delmar
Chinese Reference• 無線個人通信系統 (Wireless Personal Communications Systems), 全華科技圖書
股份有限公司
• 數位移動通訊 –無線寬頻網路, 儒林圖書股份有限公司• 無線通訊網路網路慨論, 文魁資訊股份有限公司• 無線通訊與網路: 滄海書局
Page 5
Wireless Communication
Lesson 1 –Introduction to wireless communication 8 Dr. Sheng-Chou Lin
Lessen 1
Introduction to Wireless CommunicationSystem
Wireless Communication
Lesson 1 –Introduction to wireless communication 9 Dr. Sheng-Chou Lin
Outline
History of Wireless Communications•Trends, Radio spectrum
Basic Definitions and Common Terminology (專門術語)•Wireless, Mobile, Cellular, PCS, WLL
Generations and Standards•Analog (1st. Gen), Digital (2nd Gen.), Wideband (3rd. Gen.)
BSS (Base Station Subsystem) Architecture•Coding•Access and Duplex Techniques•Modulation•RF System•Air Interface Challenges
Wireless System Design Overview•Coverage Prediction
Page 6
Wireless Communication
Lesson 1 –Introduction to wireless communication 10 Dr. Sheng-Chou Lin
Lesson 1 Objectives
Trace cellular history from beginning of radio to today
Recognize the frequencies used by cellular systems
Differentiate between MSAs and RSAs
Discuss basic RF principles
Illustrate major radio systems around world
Make a comparison of common mobile radio system
Show trends in cellular radio and personal communication
Wireless Communication
Lesson 1 –Introduction to wireless communication 11 Dr. Sheng-Chou Lin
Lesson 1History of Cellular Communications
Page 7
Wireless Communication
Lesson 1 –Introduction to wireless communication 12 Dr. Sheng-Chou Lin
Lesson 1History of Cellular Communications
The days before radio.....• 1680 Newton first suggested
concept of spectrum, but forvisible light only
• 1831 Faraday demonstrated thatlight, electricity, and magnetismare related
• 1864 Maxwell developedelectromagnetic theory: spectrumincludes more than light
• 1890 First successful demos ofradio transmission
UN S
LF HF VHF UHF MW IR UV XRAY
Wireless Communication
Lesson 1 –Introduction to wireless communication 13 Dr. Sheng-Chou Lin
Lesson 1History of Cellular Communications
Less than 100 years of Radio...
• 1914 Radio first used for practicalcommunication in WWI (War I)
• 1920 First radio broadcasting
• 1940 Radar first used in WWII(War II)
• 1950 First commercial television
• 1960 First mobile telephony
MTS, IMTS
Page 8
Wireless Communication
Lesson 1 –Introduction to wireless communication 14 Dr. Sheng-Chou Lin
Progress inRadio Communications
RADAR
Spark VacuumTubes
DiscreteTransistors
MSILSI
VLSI,ASICS
DevicesModulation CW AM FMFSK PM PSK QAM DQPSK GMSK
Radio Communication SystemsMobile Telephony30-50MHz
150MHz450MHz800MHz
1900MHzAM Bcst1MHz FM Bcst100MHzVHF-TV Bcst
UHF-TV Bcst
HFAmateurMarineMilitary
VHFLand Mobile
MicrowavePoint-to-Point
MicrowaveSatellite
1920 1930 1940 1950 1950 1960 1970 1980 1990Time
Wireless Communication
Lesson 1 –Introduction to wireless communication 15 Dr. Sheng-Chou Lin
Overview of the Radio Spectrum
3 4 5 6 7 8 9 10 12 14 16 18 20 22 24 26 28 30 GHz
0.3 0.4 0.5 0/6 0.7 0.8 0.9 1.0 1.2 1.4 1.6 1.8 2.0 2.4 3.0 MHz
3 4 5 6 7 8 9 10 12 14 16 18 20 22 24 26 28 30 MHz
30 40 50 60 70 80 90 100 120 140 160 180 200 240 300 MHz
0.3 0.4 0.5 0/6 0.7 0.8 0.9 1.0 1.2 1.4 1.6 1.8 2.0 2.4 3.0 GHz
Broadcasting Land-Mobile Aeronautical Mobile TelephonyTerrestrial Microwave Satellite
AM
UHF TV 14-69
FM VHF TV 7-13VHF LOW Band VHF
UHF GPSDCS, PCSCellular
LORAN Marine
Short Wave -- International Broadcast -- Amateur CB
Page 9
Wireless Communication
Lesson 1 –Introduction to wireless communication 16 Dr. Sheng-Chou Lin
Evolution of Public MobileTelephony
1960 1990
Standards EvolutionMTS150MHz IMTS150MHz
450MHz
AMPS800MHzN_AMPSD-AMPS
CDMA
PCS1900MHzGSM
CDMAAMPS, etc
ESMR800MHz
System Capacity Evolution - UsersDozens Hundreds 100,000 1,000,000
Technology EvolutionAnalog AM, FM Digital Modulation
DQPSKGMSK
Access StrategiesFDMATDMACDMA
Vacuum Tubes Discrete Transistors MSI LSI VLSI, ASICs
AMPS = Advanced Mobile Phone SystemN_AMPS = Narrowband AMPS (Motorola)D-AMPS = Digital AMPS (IS-54 TDMA)
ESMR = Enhanced Specialized Mobile Radio
PCS-1900 = Personal Communication SystemsFDMA = Frequency Division Multiple AccessTDMA = Time Division Multiple AccessCDMA = Code Division Multiple Access
Wireless Communication
Lesson 1 –Introduction to wireless communication 17 Dr. Sheng-Chou Lin
Trends inRadio Communications
Time
Cost
Complexity
Capacity
Radio Frequency
Analog Digital
Centralized Distributed
Technology:
SystemOrganization:
Page 10
Wireless Communication
Lesson 1 –Introduction to wireless communication 18 Dr. Sheng-Chou Lin
North American Cellular
During the 1970, the FCC (USA Federal CommunicationsCommission) allocated 40 MHz. of spectrum in the 800 MHz. rangefor public mobile telephony. Canada joined the vision.•FCC adopted the AMPS (Advanced Mobile
Phone System) standard, creating cellular aswe know it today
•The USA was divided into 333 MSAs (MetropolitanService Areas) and over 300 RSAs (RuralService Areas)
By 1990, all MSAs and RSAs had competing licenses granted and atleast one system operating. Canadian markets also developed.
In 1987, the FCC allocated 10 MHz. of expanded spectrum In the 1990, additional technologies were proposed for cellular
•TDMA (IS-54,55,56)•CDMA (IS-95)
333 MSAs300+ RSAs
Wireless Communication
Lesson 1 –Introduction to wireless communication 19 Dr. Sheng-Chou Lin
History of wireless Com. (Mid1900s)
1946: First commercial mobile telephone system in the US•FCC allocated 3 channels in the 150MHz range in St.Louis for the public.
One year later, the NY-to-Boston corridor was covered.These were allmanual systems, requiring operator assistance.
1947: concept of “Cells”developed by AT&T•By dividing an area into small cell,a concept called “frequency reuse”could
be employed to increase capacity
1954: US Navy first used the moon as a satellite•The moon was used as a passive reflector to bounce a signal-For a few
years later,the moon was used for a communication |ink betweenWashington D.C.and Hawaii (when available!)
1957: Russia launched the first active Satellite, Sputnik l
Page 11
Wireless Communication
Lesson 1 –Introduction to wireless communication 20 Dr. Sheng-Chou Lin
History of wireless Com. (Analog Cellular)
1971: AT&T propose “High Capacity Mobile Phone Service”to theFCC•Outlining feasibility of “cellular radio',.The service was later named the“Advanced Mobile Phone Service (AMPS)and development licenses weregranted in the mid-70,s.
1981: Nordic Mobile Telephone(NMT) launched in Scandinavia•First commercial analog cellular mobile system in the world.First used
spectrum in the 450MHz range,later up-banded to 900MHz range.
1983: Advanced Mobile Phone Service (AMPS)launched in Chicagoby AT&T•After years of development and licensing resolution,the first cellular system in
the U.S.was launched on October 13th1983.
1985: Total Access communications System (TACS)launched in theUnited Kingdom
Wireless Communication
Lesson 1 –Introduction to wireless communication 21 Dr. Sheng-Chou Lin
History of wireless Com. (Digital) 1992: Global System for Mobile Communications (GSM) launched
in Europe•First commercial digital cellular mobile system
1992: AMPS networks first upgraded to lS-54 TDMA in U.S.
1995: First PCS network launched in U.S.•APC (now a Voice stream network) in Washington D.C.using GSM
1996: lS-95CDMA launched in U.S.
1998: lTU receive 10 proposals for a terrestrial 3rd Generationwireless cellular standard•Most using some type of wideband CDMA or wideband TDMA
1999: ITU selects 5 technologies in November for lMT-2000
2001: NTT DocoMo aiming for initial launch of W-CDMA(Oct.)
Page 12
Wireless Communication
Lesson 1 –Introduction to wireless communication 22 Dr. Sheng-Chou Lin
AMPS Cellular SpectrumUplink and Downlink Bands
Cellular telephony provides Full-duplex communications•two-way simultaneous conversation requires simultaneous transmission in
both directions•25 MHz. band of frequencies used for mobile transmission (Uplink)•25 MHz. band of frequencies used for cell site transmission (Downlink)
Cellular bands divided equally between two competing operators•A (Non-wireline) operator•B (Wireline) operator (in USA, originally only Telcos were eligible)
824 835 845 870 880 894
869
849
846.5825
890
891.5
Uplink (Reverse Path) Downlink (Forward Path)
Paired Bands
Frequency, MHz
Uplink
Downlink
Wireless Communication
Lesson 1 –Introduction to wireless communication 23 Dr. Sheng-Chou Lin
The Resource: AMPS SpectrumFrequencies and Channel Numbers
824 835 845 870 880 894
869
849
846.5825
890
891.5
Uplink (Reverse Path) Downlink (Forward Path)
Paired Bands
Frequency, MHz
A (non-Wireline) B (Wireline) BAA7997166663331991-
1023 Channel Numbers334
An operator authorized frequency block contains 416 channels In a frequency plan, we assign specific channels to specific cells,
following a reuse pattern which restarts with each Nth cell Uplink and downlink bands are paired mirror images
•A channel includes one uplink and one downlink frequency
Page 13
Wireless Communication
Lesson 1 –Introduction to wireless communication 24 Dr. Sheng-Chou Lin
Mobile Radio System Types
Paging systems: simplex•numeric, alphanumeric, voice
Cordless: full duplex Cellular Telephone systems
Paging systems
Cordless systems
Cellular systems
Wireless Communication
Lesson 1 –Introduction to wireless communication 25 Dr. Sheng-Chou Lin
What is Multiple Access
Since the beginning of telephony and radio,system operators have tried to squeeze themaximum amount of traffic over each circuit
Types of Media Examples:• Twisted pair - copper• Coaxial cable
• Fiber optic cable• Air interface (radio signals)
Advantages of Multiple Access• Increased capacity: serve more users• Reduced capital requirements since
fewer media can carry the traffic• Decreased per-user expense• Easier to manage and administer
Transmission
Medium
Each pair of usersenjoys a dedicated,
private circuit throughthe transmission
medium, unaware thatthe other users exist.
Multiple Access:by multiple, independent users .
Page 14
Wireless Communication
Lesson 1 –Introduction to wireless communication 26 Dr. Sheng-Chou Lin
What is a Channel
The physical transmission medium is a resource that can be subdividedinto individual channels according to different criteria depending on thetechnology used
Here’s how the three most popular technologies establishchannels:
Channel: An individually-assigned, dedicatedpathway through a transmissionmedium for one user information
Power
FrequencyTime
Power
FDMA
TDMA
CDMA
FrequencyTime
Power
FrequencyTime
FDMA (Frequency Division Multiple Access)• each user on a difficult frequency• a channel is a frequency
TDMA (Time Division Multiple Access)• each user on a different window period in time (time slot)• a channel is a special time slot on a special frequency
CDMA (Code division Multiple Access)• each user uses the same frequency all the time,but mixed with
different distinguishing code patterns• a channel is a unique code pattern
Wireless Communication
Lesson 1 –Introduction to wireless communication 27 Dr. Sheng-Chou Lin
Access Methods
FDMA Frequency Division Multiple Access•each user has a separate radio frequency•radio receiver recovers user, ignores others
TDMA Time Division Multiple Access•each user occupies a time slot in a sequence which
repeats continuously•recover only user bits, ignore others
CDMA Code Division Multiple Access•input from user is coded into a composite bit
stream which occupies a large spectrum•composite bit stream received at other end•user’s code applied to composite bit stream•User’s input is recovered•Users’codes are orthogonal (non-interfering)
Frequency
User 1 User 2 User 3 User 4 User 5
Time
User 1
Code 1XOR
XORCode 1
User 1
Composite
FDMA
TDMA
CDMA
1 2 3 4 5 6
Page 15
Wireless Communication
Lesson 1 –Introduction to wireless communication 28 Dr. Sheng-Chou Lin
Modulation by Analog Inputs
For example, let’s use this analogwaveform to modulate a signal.
The basic, unchanging, steady radiosignal without modulation is called a“carrier”Characteristics of the carrierwhich we could modulate:
Amplitude (i.e., strength)example: AM radio broadcasting
FrequencyFM broadcasting,Voice transmissionin AMPS cellular
Phase
Modulation is the process of varying some characteristic of aradio signal in order to convey informationVoltage
Time
Notice thatfrequency and
phase modulationlook very similarwith this kind of
input.
Wireless Communication
Lesson 1 –Introduction to wireless communication 29 Dr. Sheng-Chou Lin
Modulation by Digital Inputs
For example, let this digital waveformmodulate a signal. No morecontinuous analog variations, now weare “shifting”between discrete levels.We call this “shift keying”
The steady radio signal withoutmodulation is called a “carrier”
Amplitude Shift KeyingASK example: digital microwave
Frequency Shift KeyingFSK example: control messages inAMPS cellular; TDMA cellular
Phase Shift KeyingPSK examples: TDMA cellular, GSM &PCS-1900
The previous example showed modulation by an analog waveform.What happens if we use a digital input?
Voltage
Time1 0 1 0
1 0 1 0
1 0 1 0
1 0 1 0
Page 16
Wireless Communication
Lesson 1 –Introduction to wireless communication 30 Dr. Sheng-Chou Lin
Circuit Switching• Space-division switching• Digital switch: bit stream, CCS
– Analog link: Phone-Switch– Digital link: Switch-Switch (improve quality using digital repeater)
• Trunks: lines connecting switches– DS-1,..., DS-4, SONET
• Data Comm. over telephone Network -> Modem
Wireless Communication
Lesson 1 –Introduction to wireless communication 31 Dr. Sheng-Chou Lin
Switching Systems Circuit Switching: Telephone Network
–A path is established for a conversation Package Switch: Message transmission
–Message is fragmented into smaller chunks (package)
–Package is routed along different paths, reassembled at the receiving end
–Rules for network operations -> Protocols
Page 17
Wireless Communication
Lesson 1 –Introduction to wireless communication 32 Dr. Sheng-Chou Lin
Wireless Comm. Definitions
Base Station (BS) Control Channel Forward Channel Full Duplex System Half Duplex System Handoff Mobile Station (MS) Mobile Switch Center (MSC) Page Reverse Channel Roamer Simplex System Subscriber Transceiver
Wireless Communication
Lesson 1 –Introduction to wireless communication 33 Dr. Sheng-Chou Lin
Basic Definitions and CommonTerminology
Wireless versus Mobile•Both terms tend to be used interchangeably,but are not the same•LMDS and microwave are wireless, but not mobile (Fixed wireless)•Cellular/PCS phones and satellites are wireless and mobile
Degrees of Mobility•Cordless phones have low mobility, Cellular have higher mobility
Cellular•The term “cellular”describes a wireless infrastructure,geographical|y
deployed as a collection of “cells", in a honeycomb structure•“Cellular”often implies the 850-900MHz•personal mobile service, as oppose to higher band services such as PCS.
More dearly referred to as “Cellular Band',
Page 18
Wireless Communication
Lesson 1 –Introduction to wireless communication 34 Dr. Sheng-Chou Lin
FDD and TDD
Duplexing: Subscriber is allowed to send simultaneous informationto BS while receiving information from BS•Frequency division duplexing (FDD): two distinct bands of frequencies are
provided•Time division duplexing (TDD):time instead of frequency is used to provided
both a forward and reverse link eliminate the need for separate forward andreverse frequency band–TDD is limited to cordless phone due to rigid timing for time slotting or
short portable access and is effective for fixed wireless access as all usersare stationary
ReverseChannel
ForwardChannel
Freq. Separation
FDD
Freq.ReverseChannel
ForwardChannel
Time Separation
TDD
Time
Wireless Communication
Lesson 1 –Introduction to wireless communication 35 Dr. Sheng-Chou Lin
MSC
BSC
IWF
PSTNPSTN
(Wireline)(Wireline)
WirelineTerminal
LocalPSTN
64 KBPS
CompressedVoice
64 Kbps
BSC
WirelessNetwork
(HLR)
• Wireless is compressed voice at 8 - 13 Kbps.
• But, transport is at 64 Kbps
• An MSC covers 6-12 EO Areas.
• Hence, transport distances are long
Wireless Transport
Page 19
Wireless Communication
Lesson 1 –Introduction to wireless communication 36 Dr. Sheng-Chou Lin
Dallas MTA Proposed Topology (1999)
Wireless NetworkWireless Network(HLR)(HLR)MSC
BSC
MSC
BSC
BSCBSC
87 BTSs
18 BTSs82 BTSs
86 BTSs
AustinFort Worth
Dallas2Dallas1
BSC
BSC
10 BTSs
15 BTSs
48 BTSs
10 BTSs
35 BTSs 16 BTSs
69 BTSs
83 BTSs
12 BTSs
Wireless Communication
Lesson 1 –Introduction to wireless communication 37 Dr. Sheng-Chou Lin
Lesson 1 Complete