Phasentreue

Phasentreue is a term used to describe the degree to which a signal or system preserves the intended phase relationships between its components or with a reference signal under changing conditions. It is especially relevant in timing, synchronization, and coherent signal processing, where accurate phase information is required for correct demodulation, beamforming, or pulse measurement. The term combines Phase and Treue, literally phase fidelity, and is used in engineering discussions to distinguish phase stability from amplitude stability.

In practice, phasentreue is affected by noise, distortion, component tolerances, and environmental factors such as temperature. High phasentreue implies that phase errors remain within tight bounds as frequency or amplitude varies. It is different from amplitude fidelity; a system may have high phasentreue yet degrade in amplitude, or vice versa.

Measurement and assessment rely on metrics like phase error, phase noise, instantaneous phase deviation, and Allan deviation in time-domain analysis. Tests include applying reference carriers, jitter injection, and environmental stress tests. Design approaches to improve phasentreue include phase-locked loop design, low-noise oscillators, clean RF front-ends, and feedback control strategies that minimize delay and distortion.

Applications span telecommunications, radar, audio reproduction, and metrology, where timing and coherence are critical. Limitations arise from trade-offs with bandwidth, phase noise, and system complexity.