Cellular+Telephony+-+1

2.1 Services 2.1.1 Text Messaging 2.1.2 Instant Messaging 2.1.3 Multimedia Messaging 2.1.4 Wireless Internet 2.2 Geographic scope 2.3 Traffic requirement 2.4 Infrastructure 3.1 QoS(Quality of Services) for cellular system 3.2 Different QoS Schemes in Cellular Network 3.2.1 Fault Tolerant Dynamic Channel Allocation Scheme 3.2.2 System Model 3.2.3 Call Admission Control(CAC) Scheme 3.3 QoS based on Mobility Prediction Technique 3.4 Road Topology based Mobile Prediction Technique 3.5 Different Services Classes 3.6 Individual QoS for Voice Services 3.7 Cellular Telephony Technology 3.7.1 3G 3.7.2 EDGE
 * List of Content **
 * Titles **
 * 1) Introduction
 * 2) Description
 * 1) Common WAN implementation issues
 * 1) Conclusion
 * 2) List of References

From relatively small beginnings in the late 1800's, the cellular telecommunications industry has grown to be one of the most important areas of electronics today. To have the ability to be reached by another man despite location, altitude, or depth has had high priority in communication technology throughout its history. Only until the late 1970’s have this been available to the general public. That is when Bell Telephone (the late MaBell) introduced the Advanced Mobile Phone Service, AMPS for short.
 * 1) **Introduction **

 Cellular phones today are used for a multitude of different jobs. They are used in just plain jibber-jabber, data transfers, corporate deals, surveillance, emergencies, and countless other applications.

 A cellular network is a radio network made up of a number of radio cells (or just cells) each served by a fixed transmitter, known as a cell site or base station. These cells are used to cover different areas in order to provide radio coverage over a wider area than the area of one cell. Cellular networks are inherently asymmetric with a set of fixed main transceivers each serving a cell and a set of distributed (generally, but not always, mobile) transceivers which provide services to the network's users.

 In other source, cellular telephony is a technique that was developed to increase the capacity available for mobile radio telephone service. Prior to the introduction of cellular radio, mobile radio telephone service was only provided by a high-power transmitter/receiver. A typical system would support about 25 channels with an effective radius of about 80 km. The way to increase the capacity of the system is to use numerous transmitter/receiver.

 Cellular networks offer a number of advantages over alternative solutions: >
 *  increased capacity
 *  reduced power usage
 *  <span style="font-family: 'Times New Roman',Times,serif;">better coverage

<span style="font-family: 'Times New Roman',Times,serif;">A good (and simple) example of a cellular system is an old taxi drivers radio system where the taxi company will have several transmitters based around a city each operated by an individual operator.

Cellular telephony has developed from being just a voice service to provide a rich collection of data and multimedia services. To enable these new services, radio access and core network standards are being defined by the 3GPP and 3GPP2 organizations, while the Open Mobile Alliance (OMA) standards organization delivers technical specifications for application and service frameworks. Some of the services are: Text Messaging is the ability to send and receive short messages on a mobile terminal. These messages are also referred to as Short Message Service (SMS) messages since the length of a message is limited. Longer messages may usually be sent too however, they are sent in parts and the mobile subscriber is billed separately for each part. If a mobile terminal receiver is turned off, or the mobile subscriber is on a call, text messages are stored in the network and delivery is retried until successful for up to a limited number of hours.
 * 1.1 **** Purpose **
 * 1.1.1 **** Text Messaging **

It has two entry types for mobile terminals that do not have a small keyboard. These are the “multi-tap” and the predictive text entries. In the “multi-tap” case, the user has to press a single key multiple times to select the desired character. With predictive text entry, a built-in dictionary tries to predict the typed word, based on the sequence of user keystrokes. High-end mobile terminals are equipped with small keyboards with a QWERTY key layout similar to the one on regular keyboards.

Text messages can be sent to any wireless phone number. The user types in the receiver’s mobile terminal number and the message will be delivered across mobile operators and also internationally. Typical billing for SMS is on a per message basis with more economical packages available for a monthly fee. Higher rates are charged for international messaging. Group text messaging is a feature that allows a mobile subscriber to send a text message to a wireless phone number that represents a group of users. Each group member is identified by his phone number so that a send operation translates to a number of text messages, one per group member.