A mobile phone, mobile, or even handphone, occasionally shortened to just a cell phone or handphone, is usually a small portable phone that can easily make and receive calls on a wireless signal network while the user is traveling in a phone service area. This is an indispensable tool for travelers who want to be able to call home or check-in with their loved ones. In fact, mobile phones are one of the most popular devices for use with the Cellular Intelligent Communication Technology (CIS) in the world today. Most everyone owns a mobile phone these days. So do not be surprised if you see someone taking one with them when you are out and about.
There are many different types of mobile phones available to subscribers today; however, the main categories are CDMA, GSM, UMTS, and TDMA. Almost all U.S. carriers offer at least one of these options. The type of cellular system that is used depends on the cost of the phone and the distance that it will be carried.
One of the first cellular systems was the GSM, which means Global System for Mobile Communication. This type of mobile phone uses a CDMA which is short for Code Division Multiple Access, which is another way of saying that each number can only be accessed by using a code composed of numbers. The subscriber units of this cellular system are programmed with the desired access code and it can dial a maximum of three numbers. The U.S. Federal communications standards allow for two different access codes to be used for a single line. Two-way and three-way cellular services are offered by most carriers.
CDMA cellular phones offer several benefits including the ability to receive calls and text messages but do not include the speakerphone capability like the UMTS unit does. The TDMA or Time Division Multiple Access allows a user to send and receive calls and text messages at the same time. A CDMA unit can also receive texts. The last type is the UMTS or Universal Mobile Telephone Service. This type of mobile phone allows a user to send and receive messages as well as place phone calls to other units in the network.
A major benefit of the GSM mobile phones is that they provide unlimited call and messaging features along with making international calls at much cheaper rates. Another reason is that GSM handsets can be used in the U.S. as SIM cards and they make calls and send text messages even when the unit is out of the country. The other major advantage is that GSM cell phones allow the users to make local calls at much cheaper rates than other mobile phones. They also allow the users to send and receive international calls at unbelievable rates. The last major advantage is that most GSM handsets have voice dialing functions that allow the users to select a certain area code to make calls and text messages from anywhere around the world.
A GSM cellphone generally has a single frequency in which it is operating, but this frequency could change over a period of time. These mobile phones can also function as walkie-talkies. This walkie-talkie feature gives you the capability of talking to a person at a specific location and the distance is calculated by measuring the distance traveled by the cellphone. However, there are certain models in which a limited-service works, and the number of calls and text messages that a user can have during one month is dependent on the specific cellular network.