Mobile Multi Media Applications
- 1. By: Khalid El-Darymli Basheer Adamu Aliyu Multimedia and Mobile Systems
- 2. Introduction Cellular Communications: - T he basics of radio telephony systems, including both analog and digital systems. - The basic components of a cellular system and identify digital wireless technologies. Global System for Mobile Communication (GSM): - A short history of network evolution - Introduction to basic GSM concepts , specifications, networks, and services.
- 3. What is a cellular mobile communication ? A cellular mobile communications system uses a large number of low-power wireless transmitters to create cells — the basic geographic service area of a wireless communications system. Variable power Levels allow cells to be sized according to the subscriber density and demand within a particular region. Mobile users travel from cell to cell, their conversations are handed off between cells to maintain seamless service. Channels (frequencies) used in one cell can be reused in another cell some distance away. Cells can be added to accommodate growth, creating new cells in unserved areas or overlaying cells in existing areas.
- 4. Mobile Communications Principles Basic Mobile Telephone Service Network
- 5. Cellular System Architecture Cells Clusters Frequency Reuse Cell Splitting Handoff
- 6. Analog Cellular Systems: 1- The Advanced Mobile Phone Service (AMPS): It was released in 1983 using the 800-MHz to 900-MHz frequency band and the 30-kHz bandwidth for each channel as a fully automated mobile telephone service. Uses frequency modulation (FM) for radio transmission. It was the first standardized cellular service in the world and is currently the most widely used standard for cellular communications. Designed for use in cities, AMPS later expanded to rural areas. Limitations: low calling capacity, limited spectrum, no room for spectrum growth, poor data communications, minimal privacy, inadequate fraud protection. 2- Narrowband Analog Mobile Phone Service (NAMPS) - It came within the second generation of analog cellular systems. - Was designed to solve the problem of low calling capacity. - It is now operational in 35 U.S. and overseas - Uses frequency division to get 3 channels in the AMPS 30-kHz single channel bandwidth. It is a US cellular radio system combines existing voice processing with digital signaling, tripling the capacity of today's AMPS systems.
- 7. Cellular System Components: Public Switched Telephone Network (PSTN) Mobile Telephone Switching Office (MTSO) Cell site with antenna system Mobile Subscriber Unit (MSU)
- 8. Digital Systems Frequency Division Multiple Access ( FDMA) Time Division Multiple Access ( TDMA ) also called (DAMPS) Code Division Multiple Access ( CDMA ) Personal Communications Service (PCS)
- 9. AMPS/DAMPS Comparison high poor Noise immunity better—easily scrambled poor Privacy authority shared cooperatively mobile slaved to base Mobile/base relationship constant frequency variable phase constant phase variable frequency Carrier type time shared bursts continuous TX/RCV type 125 to 300 conversations per cell 40 to 50 conversations per cell Subscriber capacity 3 or 6 1 Conversations per channel 30 kHz 30 kHz Channel bandwidth 824 MHz to 891 MHz 824 MHz to 891 MHz Spectrum Digital Analog
- 10. Evolution of Mobile Telephone Systems Cellular Subscriber Growth Worldwide
- 11. GSM Milestones in the GSM history
- 12. What is a GSM? It is a digital cellular radio network which allows one network channel to support multiple conversations by means of time division multiplexing (TDM or TDMA). GSM was designed by the GSM design group during the latter part of the 1980s, and is the major digital cellular radio network in Europe, where it is used in the 900MHz radio band. GSM has been standardized to 900MHz, 1800MHz and 1900MHz, and continuous to grow through out Europe, Africa, Asia Pacific and the Americas. GSM is one of the major contenders for becoming the de facto technical standard for digital cellular networks and personal communications systems.
- 13. The Switching System: Home Location Register (HLR) Mobile Services Switching Center (MSC) Visitor Location Register (VLR) Authentication Center (AUC) Equipment Identity Register (EIR) The GSM Network Additional Functional Elements: Message Center (MXE) Mobile Service Node (MSN) Gateway Mobile Services Switching center (GMSC) GSM Interworking Unit (GIWU) A basic GSM network The Base Station System (BSS) Base Station Controllers (BSCs) The Base Transceiver Stations (BTSs).
- 14. GSM Network Areas The GSM network is made up of geographic areas, as shown in figure. The cell is the area given radio coverage by one base transceiver station. The GSM network identifies each cell via the cell global identity (CGI) number assigned to each cell. The location area is a group of cells. It is the area in which the subscriber is paged. Each LA is served by one or more base station controllers, yet only by a single MSC. Each LA is assigned a location area identity (LAI) number. An MSC/VLR service area represents the part of the GSM network that is covered by one MSC and which is reachable, as it is registered in the VLR of the MSC The PLMN service area is an area served by one network operator
- 15. GSM Subscriber Services Telephony (also referred to as teleservices) and data (also referred to as bearer services). Dual-tone multifrequency (DTMF) Facsimile group III Short message services Cell broadcast Voice mail Fax mail
- 16. Supplementary Services Call forwarding Barring of outgoing calls Barring of incoming calls Advice of charge (AoC) Call hold Call waiting Multiparty service Calling line identification Presentation/restriction Closed user groups (CUGs)
- 17. Basic Operation: 1- Mobile Station Initialization: System Broadcast Information. Register with the System
- 18. … continuous ,,, Basic Operation, 2- Mobile Call Organization: 1 3 2 4 5
- 19. … continuous,,, Basic Operation, 3- Call Handover: 4- Ending a Call : Signal Quality Levels Short Burst Time Align Voice Adjacent Cell Freq. List Tune to New Channel
- 20. … continuous,,, Basic Operation, 5- Receiving a Call on a Mobile: MS receives the channel number of the paging channel to monitor Request Service Page Request Assign a Channel The MS will listen to this channel until it hears its identification number
- 21. What is Special about 3Gs ? Third Generation System promising a wide range of personal mobility features using a multimedia-like phone . home shopping, interactive education and training with virtual reality support, navigation, multi-media multi-party consultation, entertainment, multi-connection surveillance, information seeking and retrieval, communicating laptop PCs and video communication.
- 22. MESSAGING SMS ability to send and receive text messages to and from mobile telephones EMS ability to send a combination of simple melodies, pictures, sounds, animations, modified text and standard text as an integrated message for display on an EMS compliant handset. MMS The Multimedia Messaging Service (MMS) confers the ability to send still images such as mobile postcards, mobile pictures, mobile screensavers, mobile greeting cards, mobile maps and business cards. Additionally, moving images, cartoons and interactive video
- 23. 3G Applications Audio VoIP Still & Moving Images Virtual Home Environment Electronic Agent Software Download
- 24. FEATURES NETWORK REQUIREMENTS Radio Controller Ntw, Node B. (Base Station) CELL PLANNING freq Alloc, Radio Interface, Wider coverage CORE NETWORK Switching, Trnasit, BACKBONE NETWORK Packet Delivery, IP Routing SUPPORT SYSTEM CHANGES Billiing, Intelligent Ntw Systems, etc
- 25. Disadvantages It is very difficult to configure WAP phones for new WAP services, with 20 or so different parameters needing to be entered to gain access to a WAP service. Compared with the installed base of Short Message Service (SMS) compliant phones, the relative number of handsets supporting WAP is tiny. WAP services are expensive
- 26. Prospects and Trends: Bigger and better screen technology Video is central to the technology demonstration Consumer electronics and mobile phones converge 3G is video in your palmwith varying small, medium or large screen sizes. The broadband bandwidth on 3G networks enables mobile multimedia
- 27. Problems and Challenges Handover Handset size Functionality