Usage of Cellphone:

Cellphone is the man made product and it plays a main role in the peoples life time and it is the safest and easiest thing to carry to any part of the world and easy to communicate with others with a help of cellphone. Cell phone plays a vital role in each and every peoples life. without cell phone there is no body. In each and every country the cell phone companies is famous and familiar to the peoples in the country and this cell phone companies launches many different kind of cell phones daily. But the make and rate of the cell phone differes from company to company and country to country also in some times. The original cell phones can be given guarantee with the acknowledgement copy. The usage of cell phones are

1. It is used to communicate at any time to any country

2. It is the easy method of communication of peoples from one country to others country.

3. The cost of call and the times of the manpower is also very less.

4. The cost of calls will be varied from one country to other countries according to the sim card usage.

This are all the main usage of cell phones in our day to day life.

What is Cdma:

Before the turn of the century, the area around Chicago Avenue and Dempster Street was mostly farmland. Starting in about 1899, stores began springing up on the corner and eventually on the surrounding blocks.The Commercial Development and Marketing Association (CDMA) is the preeminent professional organization devoted to commercial development in the chemicals and materials industries, with a focus on the full spectrum of applicable development approaches. To advance this important charter, we are bringing together industry thought leaders at the 2009 Commercial Development Conference: Growth in Performance Chemicals and Materials, planned for early June. This is a step-forward event - CDMA 2009 is an expression of CDMA's mission, providing a unique forum for richer, more direct dialogue on the commercial development challenges facing the chemicals and materials industries. No other professional, scientific, or trade organization addresses this important space.

The History of CDMA:
This is the main character to produce this kind of cdma phones. It was created to provide defence ministers with a forum to discuss such things as confidence- and security-building measures, peace support operations, civil-military cooperation, international drug and arms trafficking, terrorism, and transnational organized crime. With the end of the Cold War and the advance of democracy in Latin America, the CDMA has emerged as the premier defence meeting in the hemisphere, with the aim of facilitating debate, analysis and the exchange of views and experiences on contemporary security issues in the Americas.This kind of facility can be used only by the particular mobile phones like Reliance, Tataindicom and etc.
These are all the main featuers and historical history of CDMA.

What is GSM:

Which stands for Global System for Mobile Communications, is a digital cellular radio network operating in all over Countries world-wide. It provides almost complete coverage in western Europe, and growing coverage in the Americas, Asia and elsewhere.In 1980, the European Conference of Postal and Telecommunications Administrations (CEPT) created the Groupe Spécial Mobile (GSM) to develop a standard for a mobile telephone system that could be used across Europe. The Europeans realized this early on, and in 1982 the Conference of European Posts and Telegraphs (CEPT) formed a study group called the Group Special Mobile (GSM) to study and develop a pan-European public land mobile system. The GSM facility can be used by many kinds of mobiles. In 1989, GSM responsibility was transferred to the European Telecommunication Standards Institute (ETSI), and phase I of the GSM specifications were published in 1990. The first GSM network was launched in 1991 by Radiolinja in Finland with joint technical infrastructure maintenance from Ericsson.Commercial service was started in mid-1991, and by 1993 there were 36 GSM networks in 22 countries. By the end of 1993, over a million subscribers were using GSM phone networks being operated by 70 carriers across 48 countries. which had grown to more than 55 million by October 1997. With North America making a delayed entry into the GSM field with a derivative of GSM called PCS1900, GSM systems exist on every continent, and the acronym GSM now aptly stands for Global System for Mobile communications.

The GSM frequency are three types:

1. GSM 900: It works in According to the frequency of DCS 900 MHZ
2. GSM 1800: It works in According to the frequency of DCS 1800 MHZ
3. GSM 1900: It works in ACcording to the frequency of DCS 1900 MHZ.

This is the main frequency used by the GSM mobiles all over the world.

Parts in Cellhone and its Usage:

There are many parts in a cellphone. This parts is different from one company to the other company according to the size of the mobile. In before days they used many parts in a cellphone each parts helps in different ways. But nowadays they have introduced a single chip which is used to do the work of more than three Chips. So the size of the circuit board comes less and the handset of the cellphone is comes too less. The major parts of the cellphones are described below.

1. Resistor: Its frequency is ohms. It is used to reduce the voltage. It has nine types of Colours. It oppose both the A/C and DC Voltage. If the Voltage is passed means the Resistor will act. If not the Voltage will not pass.

2. Capacitor: Its frequency is fereds it is the highest. The lowest frequency is lowest. It allows A/c and it blocks the DC Current. The Capacitor has conductor and insulator. The Conductor it allows the electricity. The insulator it does not pass electricity.

3. Current: It is nothing but power supply. Two types of Current A/C and D/C

4. Voltage: Two types of Voltage A/C and D/C

5. Coil: It is used to remit some voltage only if there is any magnetic. If the magnet is there means the magnetic field will bouch the coil and then the voltage will be formed in a coil. It is nothing but to remit some Voltage.

6. Transformer: It is nothing but the coil according to the activation of it.

7. Diode: The Diode is nothing but emiting lights positive(+) and negative(-). It has anode and cathode. It allows Dc and it oppose A/C according to the frequency of it. There are three types of Diode.

a) Dennel Diode
b) Led Diode
c) Tunnel Diode.

These are all the main parts of the cellphone which is used to work and communicate with each other with the help of frequency..

Major Problem Cellphone Occurs:

The cellphone is the easiest and comfortable to carry to any part of the world. This cellphone is used to communicate from any part of the world. The first enemy is the water, If the phone drops in to the water then the mobile phone will be in a dead condition. There are many problems faced my the mobile phones. The major problems are described below:
1. Dead Condition (The Whole mobile should be checked)

2. The Display of the mobile is Invisible (Display Prob or Display Connector Problems)

3. The sim card what u have inserted in the mobile phone does not exist (Sim Card Connector Problem)

4. The light of the mobile phone is not working (Led Problem)

5. Suddenly mobile goes to Switch Off Condition (The Battery Problem (or) CPU Problem)

6. The Battery is full but the mobile is switched off when i was in call, it is an (Battery Problem)

7. The Key pad is not working (It is a keypad prob (or) Some dust particles inside the key pad)

This are all the major problems of the mobile phones. While working in a good condition.