1. Week-4 (Lecture-1) 3G Technology: Offer broadband mobile communications with voice, video, graphics, audio and other information. 3 important Generations of mobile computing: (1G) Analog: Voice calls inside one's country without roaming facilities. (2G): Digital mobile phone systems added fax data and messaging capabilities voice telephone service in many countries offering worldwide roaming. (3G): Multimedia services High speed data transfer to mobile devices, Internet services through mobile phones.

2. Week-4 (Lecture-1) 3G Features: information is split into separate but related packets before being transmitted and reassembled at the receiving end. Access of internet and its services i.e. WWW. Speeds of up to 2 Megabits per second (Mbps). Increase bandwidth. 3G Applications: Web Browsing file transfer Home Automation (the ability to remotely access and control in-house appliances and machines).

3. Week-4 (Lecture-1) (3G Technology History Graph)

4. Week-4 (Lecture-1) What is Duplex meaning? Allows simultaneous two-way data transfers. Communication (base station to mobile device) is called the downlink Communication (mobile device to base station) is called the uplink.

5. Week-4 (Lecture-2) Some 3G Concepts: Simplex, Duplex, Multiplex Communication: SimplexDuplexMultiplex One communication is allowed from sending to receiving device. Mobile phones allows two way communication at time t1 and t2 Both side communication is allowed at one time “t”.

6. Week-4 (Lecture-2) Symmetric Vs Asymmetric transmission: Symmetric: If the data in the downlink and the data in the uplink is transmitted at the same data rate. Probably be the case for voice transmission Asymmetric The same amount of data is sent both ways.

7. Week-4 (Lecture-2) Packet Switching Vs Circuit Switching : Packet SwitchingCircuit Switching Variable rate data stream(packed) over a shared connection Constant rate data stream(packed) over some dedicated connection characterized by a fee per unit of information.characterized by a fee per time unit of connection time, even when no data is transferred Low reliable, subject to congestionHighly reliable

8. Week-4 (Lecture-2) How 3G Network works? Smaller regions (shorter ranges) Allow higher user density and faster transmission rates. They are also called "hot spots". The 3G network might be divided up in hierarchical fashion: Macro cell - The area of largest coverage, e.g., an entire city. Micro cell - The area of intermediate coverage, e.g., a city Centre. Pico cell - The area of smallest coverage, e.g., a "hot spot" in a hotel or airport.