Sisendsignaal

Sisendsignaal, Estonian for "input signal," is the signal that is applied to a system or device to drive its behavior. It acts as the cause or command that the system responds to, in contrast to the output signal, which is the system’s response.

Input signals can be electrical (voltage or current) but may also be mechanical, optical, or acoustic quantities that are converted to electrical form by sensors or actuators. They can be analog and continuous in time, described as u(t), or digital and discrete, described as u[k]. Inputs can be time-varying, static (DC), or patterned, and may include noise, distortion, or uncertainty.

In different fields, the sisendsignaal has a central role. In control theory, it is the control input that determines the plant’s dynamics. In signal processing, it is the data entering a filter or processor. In testing and measurement, it is the excitation used to probe a system’s response. The characteristics of the input—amplitude, frequency content, phase, and timing—influence how the system behaves and how accurately its properties can be inferred.

Practical considerations include conditioning and interfacing the input path. Signals are often amplified, filtered, or impedance-matched, and may be digitized via analog-to-digital conversion for digital processing. Proper handling of the sisendsignaal is essential for achieving desired performance, stability, and measurement accuracy in engineering systems.