1 / 68

Third Generation (3G) Mobile Technology

Third Generation (3G) Mobile Technology. CSCI 6404 Presented By H. Abou-Dib J. Rouse M. Ibrahim Khan B. Shehzad. Introduction. The basic concept of cellular phones began in 1947

kenyon-turner
Télécharger la présentation

Third Generation (3G) Mobile Technology

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Third Generation (3G) Mobile Technology CSCI 6404 Presented By H. Abou-Dib J. Rouse M. Ibrahim Khan B. Shehzad

  2. 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.

  3. 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.

  4. 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

  5. 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.

  6. Frames, slots, and channels A frame is an all inclusive data package. A sequence of bits makes frame Slots hold individual call information within the frame, that is, the multiplexed pieces of each conversation as well as signaling and control data Channels handle the call processing, the actual mechanics of a call

  7. IS-54B, IS-136 frame with time slots

  8. IS-54B time slot structure

  9. 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.

  10. Cells

  11. 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.

  12. 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.

  13. 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.

  14. 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.

  15. 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

  16. 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.

  17. 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"

  18. 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.

  19. 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.

  20. 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.

  21. Global Migration Goals IMT-2000 GOAL CDMA TDMA 3GPP2 3GPP WP-CDMA Global CDMA I Global CDMA II WIMS WCDMA/NA UTRA cdma2000 W-CDMA TD-SCDMA UWC-136 DECT USA USA Korea USA Japan China Europe Europe

  22. VIDEO CONFERENCING VIDEO TELEPHONY TELESHOPPING ELECTRONIC NEWSPAPER IMAGES/COMPLEX DATA TYPES SERVICES Broadband Sophistication TELEBANKING FINANCIAL SERVICES DATABASE ACCESS INFORMATION SERVICES E-MAIL VOICE 1E4 kbit/s 1000kbit/sec 100kbit/sec 10kbit/sec Global Services: 2G->3G

  23. High-Level 3G Digital Network Architecture Wireless Access Network (UNI) Core IP Network (NNI) Packet Data Network (Internet) IP or X.25 GSM GPRS EDGE WCDMA GPRS GPRS+

  24. 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

  25. 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.

  26. Cells

  27. 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.

  28. 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)

  29. 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.

  30. 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.

  31. 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!

  32. UWC Coverage Statistics

  33. UWC Coverage Statistics

  34. 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.

  35. 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.

  36. Cellular Coverage • In most first-world countries, there is “dense” packing of cellular sites, leading to a medium-quality coverage area.

  37. Future Broadcast Methods:Hacking Hardware

  38. Case StudyJAPAN Land of Rising Sun Land of Mobile Internet First Country to offer 3G

  39. 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

  40. North America • 6 million users surfing the net on their WAP • No i-Mode • 50% of North American by the year 2003 • 120 million GSM users today

  41. Services of Wireless Consumer and corporate solutions, like ·E-mail ·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

  42. i-mode Company: NTT DoCoMo Speed: 9.6 Kbps x 14 times 2 Mbps in 2003 Subscribers: > 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.

  43. EZweb and EZaccess Companies: IDO and Tu-Ka Speed: Up to 64 kbps Subscribers: > 6.1 million Standard: 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

  44. J-Skyweb Company : J-Phone Subscribers: > 5.5 million Code: 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.

  45. WAP vs i-mode • WAP is a protocol I-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

  46. 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.

More Related