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Wireless communications Prof. Sheldon Lou College of Business Administration CSU San Marcos
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What will be covered? Fundamentals How is information (voice, data) sent and received without wires? What are Wi-Fi, Bluetooth, WiMax, GPS, and RFID? How do they work? How to set up a Wi-Fi network? What is GPS? How is it used? What is a Radio Frequency ID? How do cell phones work? What is CDMA? What is GSM? What is 3G? What is 4G? Business opportunities
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Wired and Wireless Communications The main difference: the medium used—wire vs. air This difference gives rise to the most attractive feature of wireless communications: the mobility. But it often results in colossal implementation issues and inferior performance for wireless communications. Bandwidth: number of uses Security reliability
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Comparison of wired and wireless communications WiredWireless BandwidthDepending on the media used, can be large Narrow in general, regulated by FCC Signal receptionReliable due to dedicated link Unreliable, signal can be blocked, reflected SecurityHigh, difficult to tap inEveryone within the range can intercept the message InterferenceVery littleSignificant because all share the same medium: air MobilityNoYes Cost?? ExpansionAdd wires?
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Basics for Wireless Communications How are signals transmitted wirelessly? How can many users make calls simultaneously (the limited bandwidth problem, TDMA, CDMA, etc.)? How can interference be reduced (the spread spectrum technology)? How can security be enhanced? Voice and data transmissions
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What is Wi-Fi? Wi-Fi (or WiFi—Wireless Fidelity) is actually 802.11, which is a set of standards established by IEEE on wireless local area networks. The Wireless Ethernet Compatibility Alliance started the Wi-Fi certification program to ensure that equipment claiming 802.11 compliance was genuinely interoperable.
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Municipal WiFi Networks Cover outdoor street level or inside buildings Large un-served market for Wi-Fi Public access and municipal government applications Fast emergency response networks
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How will cities use WiFi? Emergency response network The Wi-Fi cloud can be dedicated to the fire department or other emergency response teams When not used for emergencies, the system can provide high speed internet access to the public Homeland security or police applications Remote security cameras Database access from the field Intelligent traffic control Use the high bandwidth network to monitor and control traffic Internet access for underprivileged areas Wi-Fi could be a cost-effective way to deliver broadband internet access City owns and controls the infrastructure that “beams” Wi-Fi
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Other WiFi Applications Hospitality Complete large hotel coverage Practical coverage of sports arenas and convention centers Education Wi-Fi ready, but many un-served venues on campuses Coverage for large venues and areas between buildings. Transportation/Logistics Fleets, manufacturing, railways, large warehouses, shipping yards, train stations and railways Critical applications already in place
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What are business opportunities? Hardware: Access Point (AP), wireless media center, etc. Providing Wi-Fi service—hot spots Installing and managing WLANs
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What is WiMax? It is actually the so-called 802.16 standard set by IEEE. Acronym for Worldwide Interoperability for Microwave Access It was designed as a wireless alternative to cable and DSL for last mile (last km) broadband access. Use a tall antenna to cover a relatively large area to provide two-directional wideband (high speed) connections wirelessly. Multiple users can be served by one base station. The new 802.16e amendment can also serve mobile users.
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What is Bluetooth? It is actually the so-called IEEE 802.15 standard Wire replacement to connect a PC or laptop to its keyboard, mouse, microphone, printer, and notepad. It handles both voice and data. Ad hoc networking of several users at short range, e.g., in a conference room
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Cellular Systems The main features of a cell phone system: multiple cells to address the limited bandwidth problem FDMA, TDMA and CDMA GSM 3G and 4G
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Some symbols k (kilo) = 1,000 kbps = one thousand bits per second M (mega) = 1 million Mbps = one million bits per second MHz = one million Hertz G (giga) = 1 billion (1,000 million) Gbps = 1 billion bits per second GHz = 1 billion Hertz
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More terms Cellular systems: WWAN (Wireless Wide Area Network) WiMax: WMAN (Wireless Metro Area Network) WiFi: WLAN (Wireless Local Area Network) Bluetooth: WPAN (Wireless Personal Area Network)
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Compare Wireless Technologies
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The future of cell phones 1G to 3G and 4G From voice only to data transmission, video, the Internet, etc. GPS TV broadcast Games Satellite radio
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