Signalamplituden

Signalamplituden denotes the magnitude of a signal, representing its strength or level. In fields such as electronics, acoustics, and telecommunications, it is typically the maximum deviation of the signal from a reference (often zero). For periodic signals, this corresponds to the peak value.

Different common measurements include peak amplitude, peak-to-peak amplitude, and RMS amplitude. Peak amplitude is the largest absolute value of the instantaneous signal. Peak-to-peak is the difference between the highest and lowest values in a cycle. RMS amplitude is the square root of the mean of the squares of the signal and is proportional to the available power in a resistive load. In many contexts, amplitude is expressed in volts for electrical signals or in decibels relative to a reference (dBV, dBmV).

Measuring and representing signalamplituden typically involves tools such as oscilloscopes, RMS meters, and spectrum analyzers. For non-sinusoidal signals, the choice of amplitude measure depends on the application—peak for peak detection, RMS for power calculations, and envelope amplitude for modulated or amplitude-varying signals.

Applications include amplitude modulation, where the information is carried by variations in amplitude; envelope detection, and dynamic range management. Excessive amplitude can cause clipping or distortion and may alter the signal-to-noise ratio. Amplitude alone does not convey phase or frequency content, which requires additional descriptors such as phase and spectrum.

In digital systems, signalamplituden is affected by sampling and quantization. Digital representations use amplitude resolution determined by the analog-to-digital converter's bit depth, and automatic gain control may adjust amplitude to fit a usable dynamic range.