Origin of modemmo(dulator) + dem(odulator)
- Modem is defined as an abbreviation for modulator-demodulator, a device that makes it possible for computers to communicate with one another without being directly connected to each other.
An example of a modem is the device used for a computer to communicate with a satellite.
- The definition of a modem is a tool that sends and receives a signal to create a network and Internet connections.
An example of a modem is a tool that lets a computer connect to the Internet.
Origin of modemmo(dulator) dem(odulator)
(third-person singular simple present modems, present participle modeming, simple past and past participle modemed)
- To transmit by modem.
modem - Computer Definition
- A device that comprises both a modulator that changes a signal in some way in the forward direction and a demodulator that changes the signal back to its original form in the backward direction, essentially reversing the modulation process. Modems operate in balanced and symmetrical pairs, with one at each end of the communications circuit and with both having the same capabilities, at least at a minimum level.There are many types of devices characterized as modems, including cable modems, conventional modems, ADSL modems, ISDN modems (terminal adapters, or TAs), line drivers, and short haul modems. See also ADSL, cable modem, line driver, short haul modem, and TA.
- A conventional modem is a signal conversion device that interfaces a digital device to an analog circuit or channel. On the transmit side of the connection, a modem accepts an incoming digital signal and modulates (i.e., changes or varies) the characteristics of an electromagnetic waveform in some way to represent that signal over an analog carrier. The modulation technique generally involves amplitude modulation (AM), frequency modulation (FM), phase modulation (PM), or some combination. On the receive side of the connection, a modem with matching capabilities accepts the modulated signal over the analog carrier and demodulates the signal to extract the information and recreate the original digital signal. Many modems are capable of operating in full duplex, simultaneously modulating signals as they transmit them and demodulating signals as they receive them. See also AM, FM, and PM.
Acronym for Modulator Demodulator, which changes information from analog form (such as that used on telephone lines) to digital form (such as that used on computers) for computer-to-computer communications. Though modems can transmit information at maximum rates of 56,000 bits per second (bps) or 56 kbps, limitations in the telephone system realistically produce modem speeds at 33.6 kbps or lower in practice. Today, modems for cable and DSL service are called digital modems, whereas those used for dial-up service are called analog modems. This terminology is somewhat misleading because all modems actually involve analog signaling. “Digital” relates to enhanced digital processing in the service provider’s systems and not within the modem per se. Cable modems and DSL modems utilize broadband signaling methods to obtain dramatically higher network speeds than traditional modems were able to obtain.
About, Inc. Modem. [Online, 2004.] About, Inc. Website. http:// compnetworking.about.com/library/glossary/bldef-modem.htm.
(MOdulator-DEModulator) A device that adapts one type of signal to another. Until the late 1990s, the term referred mostly to analog modems, which allow a computer or terminal to transmit data over a standard dial-up telephone line. Since the advent of cable and DSL connections, the term commonly refers to other types (see cable modem, cellular modem, DSL and VoIP modem). The remainder of this definition pertains only to analog dial-up modems, which convert digital data pulses from the computer to audio tones that analog telephones accept. New computers no longer come with an analog modem; however, one can be easily added via USB. For control, most analog modems use the Hayes AT instruction set (see modem status signals and AT command set). From 300 to 56,000 Bits Per Second At 56 Kbps downstream, the ITU's V.92 was the last standard for dial-up modems. Decades ago, the first modems transmitted 300 bps, and while 56 Kbps (56,000 bps) might seem like a huge leap, it is extremely slow for Web page retrieval. For example, a high-speed cable modem can support 100 Mbps (100,000,000 bps). See V.92. Like a Telephone A modem dials the line and answers the call. While performing digital-to-analog and analog-to-digital conversion, it also provides error correction and data compression. A modem's automatic feature negotiation adjusts speed downward to synchronize with a slower modem at the other end as well as to accommodate noisy lines.