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Third Generation (3G) Mobile Technology
CSCI 6404Presented ByH. Abou-Dib J. Rouse M. Ibrahim Khan B. Shehzad
Introduction
The basic concept of cellular phones began in 1947
The FCC limited the amount of frequencies available in 1947, the limits made only twenty-three phone conversations possible simultaneously in the same service area
1968 AT&T and Bell Labs proposed a cellular system.
Timeline
1978 AT&T and Bell Labs conducted public trials with 2000 customers.
1979 saw a similar system in Tokyo 1981 Motorola and American Radio Telephone started
another system. 1982 FCC authorizes commercial cell service. 1983 AMPS (Advanced Mobile Phone Service) introduced. Demand was huge. 1982 system standards were already
taxed. By 1987 over one million subscribers. Airways were crowded. FCC opens the 800Mhz band for alternative cell technologies.
Important Dates
In 1988, the Cellular Technology Industry Association (CTIA) was established
The TDMA Interim Standard 54 or TDMA IS-54 was released in early 1991
In 1994, the FCC announced it was allocating spectrum specifically for PCS technologies at the 1900 MHz band
TDMA IS-136 (Time Division Multiple Access) is an update to TDMA IS-54, also called Digital AMPS or D-AMPS
CDMA IS-95 (Code Division Multiple Access) is based on a form of spread spectrum technology that separates voice signals by assigning them digital codes within the same broad spectrum
GSM (Global System for Mobile Communications) is based on a improved version of TDMA technology
Analog vs. Digital: First Take
Analog Service: A method of modulating radio signals so that they can carry information such as voice or data.
Digital Service: A method of encoding information using a binary code of 0s and 1s.
Frames, slots, and channels
A frame is an all inclusive data package. A sequence of bits makes frameSlots hold individual call information within the frame, that is, the multiplexed pieces of each conversation as well as signaling and control dataChannels handle the call processing, the actual mechanics of a call
IS-54B, IS-136 frame with time slots
IS-54B time slot structure
How Cellular Phones Work
Cell-Phones use high frequency radio signals to communicate with “Cell Towers”
Current frequency range is 806-890 Mhz
1850-1990 Mhz is for the newly allocated “PCS” frequency range.
Cells
Cells
Macro-Cell: 1-2 miles apart. Up to 20 in rural areas.
Micro-Cell: Some buildings have their own Micro-cells to supplement Macro-cells.
Pico-Cells:Connect cell phones to the PSTN and allows it to be used as a cordless phone.
Analog vs. Digital
Analog Service: A method of modulating radio signals so that they can carry information such as voice or data. Broadcasts audio as a series of continuously changing voltages levels representing the amplitude of the conversation.
Digital Service: A digital signal quantizes the voltage levels into a number of bins (typically 28 or 256 representing an 8-bit encoding). These bins are encoded as a binary number and sent as a series of ones and zeros. This allows for digital compression in the encoding stage enabling voice to be sent at as little as 8000 bits per second.
Encoding and Multiplexing FDMA: Frequency Division Multiple Access
is exclusively used on all analog cellular systems each channel is 30 kHz
TDMA: Time Division Multiple Access builds on FDMA by dividing conversations by
frequency and time fits three digital conversations into a FDMA channel
CDMA: Code Division Multiple Access systems have no channels encodes each call as a coded sequence across the
entire frequency spectrum conversation is modulated, in the digital domain,with
a unique pseudo-noise code.
Encoding and Multiplexing
GSM: Global System for Mobile Communications Modified and far more efficient version of TDMA timeslots are smaller than TDMA and implements
frequency hopping Almost a packet network by design.
Security ?
Analog phones transmit in plain FM, and provide no security.
Encryption is used in TDMA and CDMA works by picking a key that is used in an equation that
compresses the audio CDMA also uses its modulation code to provide
increased security
Wireless Data
Analog modems works on any cellular system by simply encoding the
digital data as audio signals average between 4800 to 9600 bits per second digital cell systems data compression damages the
analog modem signal Packet Data
Use some of the channels of the TDMA or FDMA (IS-136 and AMPS standards) network as large aggregated digital data lines.
CDPD standard allows cell phones on the network to insert packets on this shared data channel without causing collisions.
19.2 kilobits per second.
Wireless Data
GSM Sends computer data as it would send voice data. Data rates in multiples of 300 bits per second up 64
kilobits per second. Referred to as GPRS: "General Packet Radio Service"
WCDMA – 3G
WCDMA can reach speeds from 384 Kbps to 2 Mbps, which represents from 6 to 35 times more than what regular landline modems can do. At that speed, wideband services such as streaming video and video-conference
higher data rates require a wide radio frequency band, So WCDMA will use 5MHz carrier compared to the narrow band of 2Ghz used by GSM
Can use current narrow band technology initially to reduce introduction costs with some loss in maximum data rates.
3G Hardware Approach
Evolutionary approach to increasing services and data rates.
Multiple competing standards in multiple countries make global integration challenging.
Long-term strategies mean incrementally higher data rates rather than discontinuous jumps.
3G Technology: RF & IP
Radio frequency transmission is key to 3G’s technology promise.
Transmitting IP over RF at decent speeds is the goal (near or above 2Mb/sec/user would be ideal).
Radio transmitting technologies such as Code Division Multiple Access, WCDMA, and Time Division Multiple Access affect the basic data rates achievable by 3G networks.
High speed radio networks and their interfaces to packet-based computer networks are the foundation of all 3G technology.
Global Migration Goals
TD-SCDMAGlobal CDMA I UTRAWIMS WCDMA/NA
Global CDMA II UWC-136W-CDMA DECTcdma2000
WP-CDMA
3GPP2
TDMACDMA
IMT-2000GOAL
3GPP
KoreaUSA USA USAJapanEurope China Europe
Global Services: 2G->3GSE
RVI
CES
VOICE
10kbit/sec 100kbit/sec 1000kbit/sec
Broadband Sophistication
DATABASE ACCESSINFORMATION SERVICES
TELEBANKINGFINANCIAL SERVICES
ELECTRONIC NEWSPAPERIMAGES/COMPLEX DATA TYPES
TELESHOPPING
VIDEO TELEPHONY
VIDEO CONFERENCING
1E4 kbit/s
High-Level 3G Digital Network Architecture
GPRSGPRS+
IPor
X.25
GSMGPRSEDGE
WCDMA
Wireless AccessNetwork
(UNI)
Core IPNetwork
(NNI)
Packet DataNetwork(Internet)
3G Data Rates and Services
High Speed Services to be Provided by 3G networks: Web Browsing, Email, FTP, Fax & VoIP -> All require serious data rates!
Nominal Data Rates (IMT-2000 goals): At least 144 Kbps in a macrocell At least 384 Kbps for an outdoor pedestrian At least 2 Mbps indoor, stationary or mobile
3G Data Rates Explained
What is a “macrocell”? This is defined by the IMT as “suburban”. In Canadian terms,
this would define, for instance, Markham Ontario from Toronto, or Cole Harbour from Halifax.
What is a “microcell”? This is “urban”, or the Municipality of Halifax. Bedford,
Halifax, and Sackville could be considered as 3 microcells in a global communication hierarchy.
What is a “picocell”? This type of cell is indoors; whether inside the CSB or inside
the World Trade and Convention Center.
Cells
3G Data Rates Explained
What is the difference between a “pedestrian” and a “highly mobile” user? Pedestrian users move slowly and usually stay within one or
two cell tower’s coverage areas. This means that lower-cost transmission technology can lead to higher data rates, and more accurate, convenient services such as subscriber location and route determination.
Highly-mobile users generally cannot be constrained to two or three pico or micro cells, and are moving at a high rate of speed (an automobile, for instance). These users must have a more robust, more expensive method of transmission in order to maintain a high data rate.
3G Integration Strategies: Heading for IMT-200x
IMT-2000 is a consortium dedicated to providing an International Mobile Telecommunications infrastructure.
Growth tends to focus on enhancing currently-installed network hardware rather than revolutionizing network towers and broadcast equipment.
Two methods for increasing our mobile data rates: Enhanced Data Rates for Global Evolution (EDGE) General Packet Radio Services (GPRS)
Enhanced Data Rates for Global Evolution
EDGE equipment is generally IP-to-Packet Radio conversion boxes.
Enabling EDGE on a TDMA network requires buying a small amount of new tower equipment, but offsets the cost of moving to a new transmission technology. It also allows TDMA networks to interface to high-speed GPRS services, thus allowing IP-to-Radio conversion and vice versa.
EDGE is currently a much-touted solution to growing our aging TDMA networks. EDGE will be compatible with the final IMT-2000 global networks, but will still use the dated TDMA technology.
General Packet Radio Services
General Packet Radio Services are the basic building blocks for changing standard RF communications into packet-based, discrete transactions. GPRS is implemented as a mixture of new radio towers, transceivers, and network hardware.
GPRS can attain whatever speeds the underlying network hardware can support, making it a particularly attractive technology for mobile spectrum providers. It also provides an “always-on” connection to allow persistent IP connections, like HTTP and Telnet, unlike most cellular connection services today.
GPRS and GPRS+ basically allow a standard TDMA device to access more than one time slot in order to transfer data.
Generic RF Carrier Techniques
TDMA / Time Division Multiple Access (NA/SA) Each cell user has a particular time slot in which to
transmit over a particular frequency band. ~48.6kbps uncompressed data rate is theoretically possible with TDMA technology.
WCDMA & CDMA / Code Division Multiple Access (Asia, Africa) Each cellular phone uses multiple “codes” to transmit
digitized data over analog transmitters within the same frequency band. The more users supported, the lower the data rate. Common rates are 36k, 64k, 96k, and, with upcoming Wideband-CDMA, a possible 1.2Mbps!
UWC Coverage Statistics
UWC Coverage Statistics
Generic RF Carrier Techniques
CDMAOne (Asia) This CDMA implementation has a direct route to IMT-2000 standards
(WCDMA) and 64kbps uncompressed performance.
GSM / Global System for Mobile Communication (Europe,Russia) TDMA-based cellular network that is totally defined in terms of radio
interfaces, air interfaces, network services, and network-to-network interfaces. GSM is a popularity leader in global communication.
PDC-P (Japan i-Mode) Personal Digital Communication-Packet is a popular TDMA-based
digital cellular packet service. It is the best-of-breed in terms of architecture; it employs digital signaling and packet-based data transfer.
Cellular Systems
Generally, cellular systems have much more subscribers than capacity.
Cellular providers deal with this by dividing the frequencies over which customer’s transmit.
Cellular towers each have their own particular piece of the provider’s spectrum, and they are organized like a beehive.
Cellular Coverage
In most first-world countries, there is “dense” packing of cellular sites, leading to a medium-quality coverage area.
Future Broadcast Methods:Hacking Hardware
Case StudyJAPAN
Land of Rising SunLand of Mobile InternetFirst Country to offer 3G
Japanese Mobile Net Users
Total: > 31.6 million i-mode: > 20.0 million EZweb: > 6.1 million J-S ky: > 5.5 million
Source: http://www.mobilemediajapan.com February 28, 2001
Desktop: Internet access trough desktop lowest among the developed nations
North America
6 million users surfing the net on their WAP
No i-Mode50% of North American by the year 2003120 million GSM users today
Services of Wireless Consumer and corporate solutions, like
Corporate data
News
Sports and information services
Entertainment
TV/movies
Travel/plain ticket/hotel
Leisure
Culture
Medical care
Electronic commerce transactions and
Banking services and Online purchasing
http://www-usa.cricket.org/link_to_database/INTERACTIVE/WAP.html
i-mode
Company: NTT DoCoMo Speed: 9.6 Kbps x 14 times
2 Mbps in 2003Subscribers: > 20.0 million Standard: cHTML Sites: 13,000 (40 000)Outline: The cheapest and most popular wireless web. Packet
switching to offer continuous connection. Largest ISP in the world.
EZweb and EZaccess
Companies: IDO and Tu-Ka Speed: Up to 64 kbpsSubscribers: > 6.1 millionStandard: HDML (handheld device markup language) Site numbers: > 5000? Outline: 2nd most popular system, but far less content
because the relative difficulty of HDML has deterred many site designers.
E-mail: 5000 chars by e-mail
J-Skyweb
Company : J-Phone Subscribers: > 5.5 millionCode: MML (mobile markup
language). similar to cHTML
Speed: 9.6 kbps Site numbers: < 4000. Clearest color images. In
third place at present, however it is seen as the main rival for i-mode because its programming code is so similar and because it also offers continuous access.
WAP vs i-mode
WAP is a protocolI-mode is a complete wireless internet service
WML vs cHTML wap implementations use a page description
language-WML. cHTML is in part, a subset of ordinary HTML.
Only I-mode tags. It is very similar to HTML. I-mode offers continuous access to the internet, no
need to dial up and waiting for response and most sites access by few button click
Is i-mode WAP Killer?
Started Feb 1999 Profit: 252.1 billion yen ($ 4.6bn)it is 23% more from last year it will be X 5 times (2003) i-mode presently covers almost all of Japan “Within 3yrs everyone will be on i-mode” in Japan 600,000 new customers signing up every month Largest ISP in the world The customer is charged the only data actually sent or received.
Is i-mode WAP Killer?
“Cell phone to talking to cell phone to using” DoCoMo’s charges $31per month DoCoMo gets 9% of the fee for every cartoon char,
melody or news service that is downloaded 3 cents per data packet transmission of 128 bytes i.e., e-mail message of 15 Japanese char >1 cents Employ IMAP4 (Internet Message Access Protocol)
able to send message to mobile phones and stored (3MB)
Message consist up to 5000 char A one-touch “Phone-to”, “Mail-to”, “URL-to” button Color LCD screens
Is i-mode WAP Killer?
NTT DoCoMo, had halt sales and advertising temporarily, last month, Why?
In terms of cost, popularity, ease of use and commercial success, WAP is being whipped out.
This title bar is a text screen that displays text messages and data (I-Mode)
Frightening News for North America
Introducing “First 3rd generation mobile communication” in 2001
9.6 kbps => 15 times 2 mbps in yr 2003 swift enough for
webcasts, interactive games and video conferencing
i-mode Moving towards North America $10bn (US) invested in AT&T i-mode with Microsoft and Sun (Java) i-mode in Europe 5bn Dutch (KPN)
3G Concept Devices
Visor Phone: wear like glass & watch like TV
Video Phone: in Walking Stick
Digital Camera for Mobile Phones
It can attach images taken by digital camera to e-mails send via mobile phone or to use as the stand by mode screen
Digital camera with CMOS sensor with 25000 pixels and output resolution of 320X240 pixels. 32768 colors
3G
Promises and Prospects
Major Obstacles for the Industry
Low Transmission rates
Services cost too much
Too much power consumption in radio modems
Poor User Interface
Approaches to Implement Wireless Data Technology
Two Complementary Approaches
Cell phones on Steroids
3G addresses only one barrier.
Transmission speed. No solution for Cost & Power.
3G uses “Rate Adaption Techniques”.
High speed only in certain places & certain time. Compromises “Anytime, Anywhere” Theme.
WAP & 3G Products:Promises are not meant to be kept!!!
WAP & 3G Products provide Partial Solutions.
WAP & WML insufficiently powerful for future generation Terminals.
WAP will be a stopgap for 3G radios proxies.
Development of small microprocessors having wireless modems.
Reversing an old Paradigm To AAA A Conceptual Framework Adaptive, Asymmetric, Ad hoc.
Info Stations
Adaptive location-dependant allocation of battery power to signal processing and communication.
Small, low power radios for a system with location dependant radio coverage.
Infostations confirm to AAA Paradigm.
Provides a source of “fuel”-Information.
Contains a radio Transceiver for low-power high data rate Internet access in a limited area.
Don’t force you to stop while you transfer information to or from internet
Automatic transfer of data.
Airport Example
Say hello to Bluetooth
Fast and secure transmission of voice & data.
Radio operates in a globally available frequency band
Digital Devices will communicate spontaneously with
Voice /Data access point.
Cable replacement.
Personal ad hoc networks.
Ensuring high speed and security.
Joint achievements of nine leading companies ( 3Com, Ericsson, Intel, IBM, Lucent, Microsoft, Motorola, Nokia & Toshiba)
More than 1300 other manufacturers joined Bluetooth family.
By 2002, Bluetooth will be built into hundreds of millions of electronic devices.
Bluetooth: Application Areas
A breathing Fusion of the Internet, Mobile Telephony, Mobile Computing and Sci-fi remote control
Internet connection
Instant Post Card
Wireless Headset
Interactive Conference
Synchronization of Phone Books, handheld device and mobile computer content.
The automatic Synchronization
Automatic synchronization of your desktop, mobile computer, notebook (PC-PDA and PC-HPC) and your mobile phone. For instance, as soon as you enter your office the address list and calendar in your notebook will automatically be updated to agree with the one in your desktop, or vice versa.
In meetings and conferences you can transfer selected documents instantly with selected participants, and exchange electronic business cards automatically, without any wired connections.
The Interactive Conference
Evolution to 3G/IMT-2000