Amplitudivärähtelyä

Amplitudivärähtely, also known as amplitude modulation (AM), is a modulation technique used in electronic communication, most commonly in radio broadcasting. It involves varying the amplitude of a carrier wave in proportion to the message signal. The carrier wave is a high-frequency electromagnetic wave that carries the information. The message signal is the information to be transmitted, such as audio or data.

In amplitudivärähtely, the amplitude of the carrier wave is changed while its frequency and phase remain constant. The strength of the carrier wave is increased or decreased according to the instantaneous amplitude of the modulating signal. At the receiver, a demodulator is used to detect these variations in amplitude and reconstruct the original message signal.

Amplitudivärähtely is a relatively simple modulation technique to implement and is widely used in AM radio broadcasting due to its ease of generation and reception. However, it is susceptible to noise and interference, which can corrupt the transmitted signal. Variations in amplitude caused by external factors can be misinterpreted by the receiver as part of the transmitted message. Despite its limitations, amplitudivärähtely remains a significant method for transmitting information, particularly in its historical and widespread application in radio.