UMTS / 3G Wireless

1. UMTS / 3G Wireless ENGR 475 – Telecommunications November 7, 2006 Harding University Jonathan White

2. Outline • What 3G Means • UMTS • Technical operating Procedures • Evolution from GSM to UMTS • Why evolve? • Types of equipment. • Problems with UMTS

3. 3G • Third Generation of mobile phones • Standard that supports data transfer greater than 2 Mbps. • IEEE 802.11 is not a 3G standard • Wide area cellular networks that support data-intensive applications. • Not just an improvement of 2G networks. • Requires new equipment and new frequency bandwidths.

4. UMTS • UMTS – Universal Mobile Telephone System • Most popular 3G wireless standard. • Combines the infrastructure of the GSM network with superior technology of the CDMA air interface. • UMTS was originally a European standard. • Widely adopted in Japan • Approx. complete deployment by the end of 2006.

5. GPRS and EDGE • GPRS – General Packet Radio Services • 2.5G protocol • Involved only software changes to the GSM network. • Used under utilized TDMA channels more effectively. • Increased data rates to a max of 170 Kbps. • EDGE – Enhanced Data rates for GSM Evolution. • 2.75G protocol. • Required minimal hardware changes • Added a new encoding scheme that allowed for more bits to be added into each time slice. • Data can now be passed optimally at 384 Kbps. • Both of these use TDMA over GSM

6. 3G - UMTS • Uses W-CDMA • 5 MHz of bandwidth for each channel. • Several thousand users can be supported on each cell site. • Offers 11 Mbps download speeds in theory. • Uplink speeds are much slower • Meaning, that you wouldn’t want your cell phone to be a web server. • Speeds for moving devices are also slower. • Most users are finding download throughput of about 384 Kbps. • However, this is still much faster than the 14.4 Kbps optimally that GSM offered.

7. 3G - Frequencies • In Europe: • Uses 1900 MHz band for uplink • And 2100 MHz band for downloading • Heavily contested bandwidth auctions. • Limited acceptance. • In Japan and South Korea: • Bandwidth is for the public’s good, so frequencies are open for cellular communications. • Highly accepted. • In North America: • Bands are used by other things (AMPS, GSM, satellite communication in the 2100 MHz band. • Must use existing frequency space. • Very limited acceptance.

8. Current US Deployment • Cingular was required as part of the AT&T buyout to deploy UMTS by the end of 2004. • However, they are only in 17 markets in 52 cities. • Markets include New York (NY), Austin (TX), Baltimore, Boston, Chicago, Dallas, Houston, Las Vegas, Phoenix, Portland (OR), Salt Lake City, San Diego, San Francisco, San Jose (CA), Seattle, Tacoma and Washington, D.C. • Also, they are only operating in the 850 MHz /1900 MHz band. • T-Mobile won a recent bandwidth auction in the 2150 MHz band, and they have begun a nationwide rollout.

9. Evolution from GSM/CDMA to UMTS • There are several nice steps from GSM to UMTS, with the wide rollout of GPRS and EDGE. • However, to convert to UMTS, the network needs to be reengineered from the ground up. • Actually uses the lower 3 layers of the OSI model.

10. Why Evolve • Killer App – Video Telephony • Never realized. • What people do use (at least in Japan): • MP3 downloads. • Potential good applications: • TV on a cellphone.

11. Other Applications • Computer / PDA replacement • Blackberry • Pager replacement • Videoconferencing • Newspaper • Diary • MySpace • Credit Card replacement. • Heightened security?

13. UMTS Problems • Web wasn’t designed for a 2 inch by 3 inch screen. • Inputting information is much more difficult. • Voice recognition would help. • Overweight handsets with poor battery life. • Poor coverage in the US. • To support full motion video on demand, base stations will need to setup every .5 miles, which isn’t feasible in rural areas. • Because it is so data intensive.