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ELE 2860 H. T. Tsui PowerPoint Presentation
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ELE 2860 H. T. Tsui

ELE 2860 H. T. Tsui

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ELE 2860 H. T. Tsui

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  1. ELE 2860H. T. Tsui • 1. The view of an H. K. Engineer • 2 A case study

  2. The World in the Eyes of an Engineer World scene Regional scene Local scene

  3. GNP • China 1 • USA 9 • Japan 4 • UK 1 • Europe 1 • HK 0.15

  4. Ranking on IT • Singapore Taiwan KoreaH.K. Market 10 7 19 23 Infrastructure 13 19 25 18 Government 1 2 15 11 Application (CO) 7 18 12 15 Application ( P) 9 14 1 23 ….. Total 3 9 14 18

  5. A case study: 3G Vs Wi Fi • Wi Fi is a wireless technology which have a data rate 5 times that of 3G • Advantages: • Based on technology in the public domain. • A Wi Fi access point (base station) cost US$ 70 ( cellular one cost more than $ 50,000)

  6. WI- FI (1) In major cities, many hot spot access points can be set up at low cost in cafés, airports, stations. Cheap: HK $ 3 per 10 minutes in Pacific Cafes in H. K. • Access Points : 200 in H. K. • 5,000 in Seoul • Voice over IP

  7. WI- FI (2) • Wi-Fi enabled devices Half the lap top sold have built in or add on wi-fi Even PDAs have this capability if higher power is allowed. wi-fi can have a range of 2.5 KM. Hot spot can be extended to cover tall building

  8. WI- FI (3) • Disadvantages Limited to within 100-300 meters from a hot spot (access point) 4W transmission power The lab top using wi-fi is not allowed to be mobile Spectrum crowded: 2.4 giga hetz

  9. Wi-fi service business is a low risk one • For PCCW • If it spend US $ 10 million, it can provide service to 28 % of urban H.K. by 2011 It can break even by 2009 For a dominant fixed line player like PCCW, wireless coverage is more simple. It can put wi-fi access point atop existing cables

  10. 3G in danger For a 3G operator The cost for a network covering H.K. is US $250 million + 6.4 millions annual licence fee

  11. Wi-fi development in US and Europe • Wi-fi has developed as a community movement. • Wi-Fi normads without an account can have free access • People opening network to entire neighbourhoods, marking access points by chalk in front of wi-fi-enabled houses. This force many local businesses to offer free access too.