Mobile Phones

Maybe you still remember the lessons of electronics on the frequency, amplitude, you probably still remember by the term modulation. modulation is to change or place the low frequency becomes higher frequency that can be sent / transmitted via the transmission media.
Modem acronym derived from modulator demodulator. Modulator is a part that converts the signal information into the carrier signal (Carrier) and ready for delivery, while the Demodulator is the part that separates the information signal (which contain data or messages) of the signal (carrier) that accepted so that the information can be well received. Modem is the combination of both, it means the modem is a two-way communication tool.
Data from the computer in the form of a digital signal provided to the modem to be converted into an analog signal. Analog signals can be transmitted through several media, telecommunications such as telephone and radio.
Arriving at the destination modem, the analog signal is converted into digital signals back and sent to the computer. There are two types of modems are physical, ie an external modem and internal modem.
Modem itself is divided into sections according to the data rate and frequency of work as an example 3GP Modem, GSM Modem, Analog Modem, ADSL Modem.
With the help of a modem device is computer-connected computer in the world so as to form a network called the Internet network.