sweepsignalen

Sweepsignalen, or swept signals, are time-varying signals in which the instantaneous frequency changes over time. They are typically monotonic, sweeping from a lower frequency to a higher one (an up-sweep) or the reverse. Such signals excite a system across a broad frequency band within a single measurement, enabling analysis of its frequency-dependent behavior in the time domain.

Common variants include linear sweeps, where frequency increases linearly with time, and exponential (logarithmic) sweeps, where frequency grows or decays exponentially. The generation of these signals relies on defining the instantaneous frequency f(t) and integrating to obtain the phase φ(t), with the relation dφ/dt = 2π f(t). Digital signal generators or software can produce the required waveform, which is then played through the system under test and recorded for analysis.

A central use of sweepsignalen is the measurement of a system’s impulse response. After recording the system’s output to the sweep, the result is deconvolved with an inverse sweep to yield the impulse response. The exponential sine sweep (ESS) variant is particularly notable for its ability to separate linear response from nonlinear distortions, improving the clarity of the recovered impulse response.

Applications span room acoustics, loudspeaker and microphone testing, and other engineering measurements where a wide frequency range must be characterized efficiently. Advantages include high dynamic range and the potential to isolate nonlinear distortions. Practical considerations include ensuring a stable measurement environment, accounting for nonlinearities, and applying appropriate gating and calibration to obtain accurate impulse responses.