What is the function of a modem in signal transmission?

The function of a modem is primarily to facilitate communication between digital devices and analog transmission mediums. Specifically, a modem converts digital signals from a computer or digital device into analog signals for transmission over traditional phone lines or other analog media. This process enables the communication infrastructure, which relies on analog signals, to effectively transmit the digital data.

The ability to convert digital signals into two distinct analog frequencies is crucial for Modulation, which is a key function of the modem. It allows multiple signals to be transmitted over the same medium by assigning different frequencies to each signal. This is essential in ensuring that the data sent from a digital source can be accurately transmitted and then converted back into its original form at the receiving end.

In this context, while other functions like amplifying signals and filtering noise are important in various aspects of data transmission and signal management, they do not encapsulate the core functionality of a modem. The main role of a modem remains the modulation and demodulation of signals, which is why the option regarding the conversion of digital signals into two distinct analog frequencies aligns best with the primary function of a modem in any signal transmission system.