Wireless Wireless C mm ni ti nC mm ni ti nCommunicationsCommunications

© Ammar Abu-Hudrouss Islamic University Gaza ١

Course SyllabusCourse Syllabusyy

References1 A Molisch Wireless Communications Wiely IEEE 2nd Edition 1. A. Molisch, Wireless Communications, Wiely IEEE, 2nd Edition,

2011. 2. Rappaport, Wireless Communications: Principles and Practice, pp p p

Prentice Hall 2nd Ed 3. D. N. C. Tse and P. Viswanath, Fundamentals of Wireless

Communication Cambridge U K 2005Communication, Cambridge, U.K., 20054. Andrea Goldsmith, Wireless Communications, Cambridge

University Press 2005.

Slide 2Wireless Communications

Course SyllabusCourse SyllabusCourse SyllabusCourse Syllabus

Course Content:Course Content:

Cellular Concept (ch. 3-Ref 2).p ( )Wireless Channel Characteristics (ch 4-Ref 2). Statistical Description of the wireless Channel.

Diversity techniques for the receiver and the transmitter (ch 13 –Ref 1)Diversity techniques for the receiver and the transmitter (ch 13 –Ref 1). Technical Challenges of Wireless Communications

Multiple access, Random access, power control

Spread spectrum : DSSS and FSSSSMIMO and Orthogonal Frequency Division Multiplexing (OFDM)Advanced topics according to the available timeAdvanced topics according to the available time.

Slide 3Wireless Communications

Course SyllabusCourse SyllabusCourse SyllabusCourse SyllabusGrading PolicyThe final course grade will be distributed as follows:The final course grade will be distributed as follows:

Quizzes and class activity 20 %Project 10 %Project 10 %Midterm exam 25 %Final exam 45 %

Plagiarism will not be tolerated at any case. Copying homework from your colleagues or project from any source will lead to severe consequences.

Slide 4Wireless Communications

Introduction

Communication is an essential need of human being e g Communication is an essential need of human being, e.g., conversation, letter.

“Wireless” used to be the only (limited and unreliable) way to communicate in ancient times.way to communicate in ancient times.

Modern wireless communications are based on the Modern wireless communications are based on the electromagnetic field theory (Maxwell’s equations, Marconi’s invention)

Slide 5Wireless Communications

Wireless Communications

Wireless is often prior to its wired counterpart and has Wireless is often prior to its wired counterpart and has become an important supplement:

Marconi’s Wireless Telegraph Wired Telegraph & Telephone Cordless, Cellular Telephone, and Telephone Cordless, Cellular Telephone, and Wireless Local Loop

Broadcast TV Cable TV Satellite TV Aloha Network Ethernet Wireless LAN

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Characteristics of Wireless Communications

Convenience and reduced cost Convenience and reduced costService can be deployed faster than fixed serviceNo cost of cable plantNo cost of cable plantService is mobile, deployed almost anywhere

Unreliable channel (attenuation fading Unreliable channel (attenuation, fading, shadowing, interference)

Complicated design and management Complicated design and management Device limitations (power supply, LCD) Limited bandwidth and expensive service Limited bandwidth and expensive service

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Basic Conceptsp Simplex, half-duplex, and full duplex Base Station Base Station Mobile Station Subscriber Transceiver Mobile Switching centre

l h l Control Channel Roamer Handoff Handoff Page

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Electromagnetic Spectrumg p

Slide 9Wireless Communications

Evolution of Wireless Communciations

Improved mobile telephone system (IMTS) Improved mobile telephone system (IMTS) developed in 1960

Full duplex services and direct-dialing23 FM channels with BW reduced to 25-30 KHz

Cellular conceptExploits the attenuation of radio signal withExploits the attenuation of radio signal with distance to achieve frequency reuse.originally proposed by D. H. Ring in 1947Bell Labs began work on cellular telephone system in the late 1960s.

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Evolution of Wireless Communications (1G)( )

Handoff was not solved until the development of micro-processor efficient remote controlled RF synthesizer andprocessor, efficient remote-controlled RF synthesizer, and switching center.

1G Cellular System•Designed in 1970s, deployed in early 1980sAnalog 42 control channels 790 voice channelsAnalog, 42 control channels, 790 voice channels•Handoff performed at BS based on received power•AMPS in US; TACS in part of Europe; NTT in Japan; C450 in West German and NMT in someWest German, and NMT in some countries. •Analog System is used

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Cellular Systemy

Mobile identification number (MIN) electronic serial number (ESN)

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Evolution of Wireless Communications (2G)( )

2G Systems 2G Systems Digital cellular telephony

Modest data support, GSM: a common TDMA technology for Europe; y pclaim about 3/4 of subscribers worldwide.IS-54 and IS-136: TDMA technology in US; c mpatible with AMPS; compatible with AMPS; IS-95: CDMA; standardized in 1993; South Korea and Hong Kong deployed it in South Korea and Hong Kong deployed it in 1995; US in 1996.

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Evolution of Wireless Communications (3G)( )

IMT-2000 comprises several 3G IMT 2000 comprises several 3G standards:

EDGE, data rate up to 473Kbps, backward compatible with GSM/IS 136 GSM/IS-136

cdma2000 (Qualcomm) data rate up to 2Mbps cdma2000 (Qualcomm), data rate up to 2Mbps, backward compatible with IS-95

WCDMA (Europe), introduces a new 5MHz channel structure; data rate up to 2Mbps;TD SCDMA (Chi ) CDMA i TDD f shi

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TD-SCDMA (China), CDMA in TDD fashion

2G to 3G evolution

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4G and LTE (long term evolution)

OFDM/MIMO Much higher data rates (50-100 Mbps)

G t t l ffi i (bit / /H ) Greater spectral efficiency (bits/s/Hz) Flexible use of up to 100 MHz of spectrum Low packet latency (<5ms) Low packet latency (<5ms). Increased system capacity Reduced cost-per-bit Reduced cost per bit Support for multimedia

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Pager Systemg y

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Pager Systemg y

Broad coverage for short messagingBroad coverage for short messaging

Message broadcast from all base stationsg

Simple terminals

Optimized for 1-way transmission

i l it i t k b ll lin many places, it is overtaken by cellular

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Cordless phonep

DC2 and DECT standards

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Bluetooth

Cable replacement RF technology (low cost)Cable replacement RF technology (low cost) Short range (10m, extendable to 100m) 2.4 GHz band (crowded)( ) 1 Data (700 Kbps) and 3 voice channels, up to 3 Mbps

Widely supported by telecommunications, PC, and consumer y pp yelectronics companies

Few applications beyond cable replacement

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IEEE 802.15.4 / ZigBee Radiosg

Low-Rate WPAN Data rates of 20, 40, 250 Kbps Support for large mesh networking or star clusters Support for low latency devices CSMA-CA channel access Very low power consumption Frequency of operation in ISM bands

Focus is primarily on low power sensor networksFocus is primarily on low power sensor networks

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Satellite Systemsy

Cover very large areas Cover very large areas Different orbit heights

GEOs (39000 Km) versus LEOs (2000 Km)GEOs (39000 Km) versus LEOs (2000 Km) Optimized for one-way transmission

Global Positioning System (GPS) use growingS t llit i l d t i i t l tiSatellite signals used to pinpoint locationPopular in cell phones, PDAs, and navigation d i devices

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Wireless Local Area Networks (WLANs)( )

01011011InternetAccess

0101 1011

AccessPoint

WLANs connect “local” computers (100m range) WLANs connect local computers (100m range) Breaks data into packets

Ch l i h d ( d ) Channel access is shared (random access) Backbone Internet provides best-effort service

P f i ( id )

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Poor performance in some apps (e.g. video)

Wifi Networks (Supporting Multimedia)( pp g )

802.11n++

Wireless HDTVand Gaming• Streaming video

• Gbps data rates• High reliability

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• High reliability• Coverage in every room

Wimax (802.16)( )

Wide area wireless network standardSystem architecture similar to cellularHopes to compete with cellular

OFDM/MIMO i li k t h l OFDM/MIMO is core link technology Operates in 2.5 and 3.5 MHz bands

Different for different countries 5 8 also usedDifferent for different countries, 5.8 also used.Bandwidth is 3.5-10 MHz

Fixed (802.16d) vs. Mobile (802.16e) WimaxFixed: 75 Mbps max, up to 50 mile cell radiusMobile: 15 Mbps max, up to 1-2 mile cell radius

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