referenssignal

Referenssignal, or reference signal, is a signal that is deliberately known and reproducible, used as a baseline against which other signals or measurements are compared. It serves to calibrate instruments, synchronize systems, or guide a control process. A referenssignal should have predictable properties—such as amplitude, phase, frequency, and waveform—to enable accurate estimation and tracking.

In telecommunications and digital signal processing, reference signals are transmitted or inserted into a communication stream to allow receivers to estimate the channel, correct timing and frequency offsets, and perform beamforming. Examples include pilot or reference symbols that occupy predefined positions within frames. These signals are designed to be stable and easily distinguishable from data, providing reliable references for channel estimation and synchronization.

In control engineering and metrology, a reference signal represents the desired output or trajectory a system aims to follow. The controller computes the error between the actual output and the reference signal and acts to reduce it. In calibration contexts, reference signals are produced by standards or masters traceable to SI units to calibrate sensors and instruments.

Key properties of a referenssignal include determinism, reproducibility, sufficient bandwidth, and low susceptibility to noise. The choice of waveform, duration, and placement depends on the application, balancing measurement accuracy with efficiency. The concept is widely used across fields, from digital communications to automatic control and precision metrology.