The Early Development and Impact of 4g Technology

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The Early Development and Impact of 4G Technology

Jane Sherman Shannon Sword

• Previous Technologies – 1G, 2G, 3G (CDMA, GSM, UMTS) – Multiplexing; Frequency, Time & Code Reasons for New Research How 4G Works – Architecture, AdHoc, IP core, OFDM Impact of 4G – economic, socio-cultural, political

• • •

1G Technology

Previous Technology – 1G “First Generation”
• Analog – Continuous in amplitude and time – Variations in the signal – disrupts over long distances Simplest type to wireless data Average between 4,800 to 9,600 bps (bits per second)

• •

2G Technology

Previous Technology – 2G
• Advantages – Digital – consists of 1s and 0s • Digital signal: 1) Low level, 2) High level, 3) Rising edge, and 4) Falling edge

Previous Technology – 2G
– Digital data can be compressed and multiplexed much more effectively than analog voice encodings • Multiplexing - multiple analog message signals or digital data streams are combined into one signal

Previous Technology – 2G
– Allows for lower powered radio signals that require less battery power – CODEC introduction - program that encodes and decodes digital data stream or signal • Translates data from digital to analog and vice versa


voice CODEC 10111001

Previous Technology – 2G
• Advantages – The digital voice encoding allows digital error checking • increase sound quality • lowers the noise level – Going all-digital allowed for the introduction of digital data transfer • SMS – “short message service” • E-mail

Previous Technology – 2G
• Disadvantages – Cell towers had a limited coverage area • Jagged Decay curve – Abrupt dropped calls – Analog – gradual sound reduction • “Spotty” coverage

3G Technology

Previous Technology - 3G
• • • Large capacity and broadband capabilities Allows the transmission of 384kbps for mobile systems and up to 2Mbps Increased spectrum efficiency – 5Mhz – A greater number of users that can be simultaneously supported by a radio frequency bandwidth – High data rates at lower incremental cost than 2G – Global roaming

Previous Technology - 3G
• CDMA – Code Division Multiple Access – Form of multiplexing – Does not divide up the channel by time or frequency – Encodes data with a special code associated with each channel

Types of Multiplexing
• FDMA - Each phone call is allocated one frequency for the entire duration of the call. • TDMA - Each phone call is allocated a spot in the frequency for a small amount of time, and "takes turns" being transmitted. • CDMA - Each phone call is uniquely encoded and transmitted across the entire spectrum, in a manner known as spread spectrum transmission.

Frequency Division Multiple Access

Time Division Multiple Access

Code Division Multiple Access


e od c


Reasons for New Research
• Even though 3G has successfully been introduced to European mobile users, there are some issues that are debated by 3G providers and users. – High input fees for the 3G service licenses – Great differences in the licensing terms – Current high debt of many telecommunication companies, making it more of a challenge to build the necessary infrastructure for 3G

Reasons for New Research
• Government are forced to support to the financially troubled operators 3G phones are expensive Lack of 2G mobile user buy-in for 3G wireless service Lack of coverage because it is still a new service – i.e. Champaign-Urbana uses 2.5G – Chicago is 3G equipped

• • •

Evolution to Fourth Generation systems

How 4G Works

What is 4G?
• Fourth Generation Technology • Faster and more reliable – 100 Mb/s (802.11g wireless = 54Mb/s, 3G = 2Mb/s) • Lower cost than previous generations • Multi-standard wireless system – Bluetooth, Wired, Wireless (802.11x) • Ad Hoc Networking • IPv6 Core • OFDM used instead of CDMA • Potentially IEEE standard 802.11n – Most information is proprietary

Communications Architecture
• Broadcast layer: fix...
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