Jatkuvalähettävät

Jatkuvalähettävät, also known as continuous transmitters, are a type of radio transmitter that emits a signal without interruption. This contrasts with pulsed transmitters, which send out signals in short bursts. Continuous wave (CW) transmission is the most basic form of continuous transmission and is often used in applications where simplicity and efficiency are prioritized.

The primary advantage of continuous transmission is its consistent signal strength and spectral purity. Because the transmitter is always on, it can achieve a stable output power, which can be beneficial for certain types of modulation and signal processing. In CW telegraphy, for instance, the presence or absence of a continuous wave is used to represent Morse code.

Continuous transmission is employed in a wide range of applications. It forms the basis for many radio communication systems, including amplitude modulation (AM) and frequency modulation (FM) broadcasting. In radar systems, continuous wave Doppler radar utilizes the principle of continuous transmission to detect the velocity of targets by measuring the frequency shift of the reflected signal.

However, continuous transmission also has drawbacks. It can be less power-efficient than pulsed transmission, especially when only short bursts of information need to be sent. Furthermore, a continuously transmitting device can be more susceptible to interference and jamming due to its constant presence in the radio spectrum. Despite these limitations, continuous transmission remains a fundamental technology in radio communications and radar.