Kantoaaltosta

Kantoaaltosta is a Finnish term used in telecommunications to denote the carrier wave, the sinusoidal signal that carries information in modulation systems. It serves as the reference signal to which information is imposed during modulation, producing a transmitted waveform that can be propagated through a channel and later recovered at the receiver. In common analog modulation schemes such as amplitude modulation (AM) and frequency modulation (FM), the carrier wave is the component that is modulated by the information signal, while the resulting spectrum comprises the carrier and sidebands.

Mathematically, a typical carrier wave is represented as c(t) = A_c cos(2π f_c t + φ), where A_c is the amplitude, f_c is the carrier frequency, and φ is the phase. The carrier’s frequency stability and phase coherence are important for efficient demodulation and for minimizing interference with adjacent channels. At the receiver, the carrier is used to recover the original information through demodulation; in coherent demodulation, a locally generated reference carrier aligned in frequency and phase is used to extract the modulating signal.

Usage and context: The term appears in Finnish telecommunications literature, engineering handbooks, and standards discussions to describe the wave that carries information in RF transmission. While the concept is fundamental across both analog and digital communications, the exact terminology may vary, with English texts frequently using “carrier” or “carrier frequency.”

Etymology: The word is a compound from Finnish roots meaning “to carry” and “wave,” reflecting its role as the wave that carries information. See also carrier wave, modulation, and demodulation.