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Unlicensed Wireless NEXTEL Wireless Phone Marketplace TLMN 645 Fall 2002 Class 6 802.11 Wireless LANs 802.11 -- applies to wireless LANs
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Unlicensed WirelessNEXTELWireless Phone Marketplace TLMN 645 Fall 2002 Class 6
802.11 Wireless LANs • 802.11 -- applies to wireless LANs • 802.11a -- an extension to 802.11 that applies to wireless LANs and provides up to 54 Mbps in the 5GHz band. 802.11a uses an orthogonal frequency division multiplexingencoding scheme rather than FHSS or DSSS.
802.11 Subgroups • 802.11b (also referred to as 802.11 High Rate or Wi-Fi) -- an extension to 802.11 that applies to wireless LANS and provides 11 Mbps transmission (with a fallback to 5.5, 2 and 1 Mbps) in the 2.4 GHz band. 802.11b uses only DSSS. • 802.11g (OFDM) applies to wireless LANs and provides 20+ Mbps in the 2.4 GHz band. • 802.11i enhance security and authentication
Wireless LAN 2.4 GHz b:DS spread spectrum g: OFDM
Wireless “hot spots” Doonsbury July 21.2002
Short Distance Wirelesssource:http://www.hotel-online.com/Neo/Trends/Wayport/WirelessInternet.html
WiFi “hot spots” in DC Found in cafes, bookstores etc.
Bluetooth • Industry standard for data up to 32 feet • Wireless personal area network • Permits separating PC in carry bag from phone in hand or earphone • Data rate 1 Mb/second • Operates in 2.4 GHz FHSS operation
NEXTELCombines Cell Phone &Dispatch • 25 kHz channels 64 kilobits/second • 6 TDMA channels • VSELP vocoder • utilizes a group of 800/900 MHz Specialized Mobile Radio (SMR) frequencies to form national network • No roaming charges
Nextel Cell Sizes • Nextel cell sites are configured in a cellular-like manner to enable the reuse of frequency coverage areas typically vary between 1–10 miles
NEXTEL Phones TDMA, TRANSMIT: 806-821 MHz, RECEIVE 851-870 MHz RF output power: 600 mw. Channel Spacing 25 KHz
Nextel Direct Connect • A distinctive chirp (or vibration) flags an incoming Direct Connect call; hit a button to respond. To initiate Direct Connect, enter the person's 7- to 10-digit • Direct Connect number (different from their phone number, but you can store it • in the phonebook, highlight the name and push to talk.)
Wireless Phone Chronology • 1st Generation: Analog • 2nd Generation: Digital • 2 1/2 Generation: New Services • Web access • email messaging (up to 160 characters) • 3rd Generation: Megabit/ second • high speed data, video conferencing
Wireless Phone Issues • Churn • Usage: Business or pleasure • Landline Displacement • Calling party pays • Enhanced Wireless Services • Prepaid wireless services • Paging, Wireless messaging, wireless data • Wireless PBX • Power, talk time and standby time
Churn • Definition: annual turnover of equipment/ service providers • Churn rate used to be 20-25% a year • Churn rate rate (1997) increased to 36%
Cellular Number Portability • A telecommunications network feature that enables end-users to retain their cellular telephone numbers when changing service providers, service types, and/or locations.
Why Is It Happening? • The Telecommunications Act of 1996 mandated that “…all LECs to begin to implement a long-term service provider portability solution that meets the required performance criteria in the 100 largest Metropolitan Areas”
When is this supposed to happen? • Original deadline was in June of 1999 • It has already happened in Britain, Australia and Hong Kong. • Cellular Telecommunication Industry Association (CTIA) asked for and received 2 extensions • Extended to March – 2000 – not met • Extended to November 24, 2002 • Extended to November 24, 2003.
Why hasn’t it happened yet? • $$$$$$$$$$$$$$$$$$$$$$$$$$ • Providers are concerned about churn rate – number of customers who either drop or switch their service • Software and hardware implementation • “There is a billion dollars to spend – do you want to spend it on an unneeded regulatory idea or to improve service?”
Why hasn’t it happened yet? Continued • Architecturally complicated • Seven components • Mobile Switch Center (MSC) • Signaling Transfer Point (STP) • Service Control Point (SCP) • SCP Management Server (SCP MS) • Local Service Management System (LSMS) • Number Portability Administration Center (NPAC) • Service Order Administration (SOA) System • Will require major switching software modifications
What are the benefits • Will remove one of the biggest hurdles between switching carriers • Will improve carriers responsiveness and service, along with competition • Easier for customers to migrate to companies with the best service or price – leaving the jilted companies to catch up – or else
Wireless Telephone Providers in DC • AT&T Digital PCS- TDMA • Verizon Analog, Digital Choice-CDMA • Cingular Analog, Digital Edge- TDMA • Nextel Digital- TDMA trunked dispatch • Sprint PCS- CDMA • T Mobile- TDMA (Old Sprint Spectrum)
Wireless Usage 2001Source CTIA • Average subscriber used phone 400 minutes/month • Average monthly bill $47.37 • Subscriber numbers 128.4 million • Wireless revenue voice $34 billion • Data revenue $545 million • 156,000 wireless emergency calls a day 108 a minute
3 G Rollout • 3G purpose multimedia bit rates to 384 kbs/s • Predicted in Japan 1.4 million, instead 400,000 • Most examples of capabilities publicity stunts • Streaming video uses tremendous battery power • 3G to be successful must either save time or be good at killing time
Streaming Video • MPEG4 streaming video, available on the Samsung SPH-X2000 phone. The company has signed an agreement with Microsoft to provide streaming video for wireless devices.
Wireless Data on Cell Phones • iStream, from VoiceStream, an early implementation of GPRS, (General Packet Radio Service, with faster wireless data service. Up to 56 kilobits per second is possible, though less than 40 kbps is more likely. you're charged not by the minute but by the chunks of data you use: $2.99 per month (on top of your regular phone bill), gets you 1 megabyte, roughly 500 screen pages.
US Wireless DataSource: BCR Aug. 2001 • AT&T: Wireless, HDML, cost depends upon use. (e.g. $6.99 includes email), no airtime • Cingular: WAP $6.99 to $13.99 , airtime billed at voice rates • Sprint: HDML, short messages, airtime at voice rates • Verizon: HDML, various plans from 10 cents/ minute to $2/min.
Blackberry (2002) • Research In Motion's (RIM) BlackBerry enterprise solution exemplifies the appeal • of wireless e-mail. RIM has over 320,000 subscribers across 14,000 organizations. BlackBerry, BlackBerry's simplicity is key: remote access to e-mail with a small form factor, always-on device enabling anytime, anywhere communication.
Blackberry Networks Supported • RIM Wireless Handhelds™ support multiple industry-leading wireless packet data networks. • DataTAC is operated by Motient Corporation in the United States. • Mobitex networks are operated by service providers such as Cingular Interactive • GPRS Network networks are operated by service providers such as AT&T Wireless and T Mobile