A frequency-response is the characterization of how a system's output magnitude and phase vary as a function of sinusoidal input frequency. Parameters: the independent variable is frequency (typically spanning DC to the system's bandwidth); the dependent variables are gain (output/input magnitude ratio, often in dB) and phase shift (output phase relative to input, in degrees or radians). The persistence mechanism is sustained use in engineering design, control analysis, and signal processing — encoded in measurement equipment, simulation tools, textbooks, and professional practice. A frequency-response fully characterizes a linear time-invariant system's behavior across frequencies, enabling prediction of steady-state response to any periodic input.\n\n[formal: responsus frequency | substrate: mind | horizon: hours | explicit: yes | epoch: 0.01]
Accepted ontology entry
frequency-response
A frequency-response is the characterization of how a system's output magnitude and phase vary as a function of sinusoidal input frequency. Parameters: the independent variable is frequency (typically spanning DC to the system's bandwidth)…
Definition
Why it is in scope
A frequency-response is a human-made analytical construct used in signal processing and control engineering to describe how a system's output varies as a function of input frequency. It is maintained through engineering practice, measurement instrumentation (network analyzers, spectrum analyzers), and theoretical frameworks — enabling designers to predict and shape system behavior across frequency bands.
Names and aliases
- frequency-responseen · CANONICAL
Relations from this entry
- cmsorsyn802qbjlss3cb2ruiyDEPENDS_ON →
Remove frequency and frequency-response has no independent variable — the concept becomes incoherent. A frequency-response is literally a function of frequency. This is a clear object-level dependency, not meta-level: the concept's operation depends on frequency as its defining parameter.
Relations to this entry
- cmsp5klrq046wjlsswdsr4g13← DEPENDS_ON
Group-delay requires frequency-response to operate: τ_g(ω) = -dφ/dω is defined as the negative derivative of the phase component of a frequency-response. Without the frequency-response concept, group-delay is incoherent.
- cmsp49ekv0413jlssad11emyp← DEPENDS_ON
A filter is defined by its frequency response (passband, stopband, cutoff). Remove frequency-response and the filter's defining characterization mechanism ceases to operate — filters are designed, specified, and understood through their frequency response.
- cmsp5klrq046wjlsswdsr4g13← DERIVED_FROM
Group delay was developed as a derived concept from frequency response analysis: τ_g(ω) = -dφ/dω extracts timing information from the phase component of a frequency response. Frequency-response existed as a characterization tool first; group-delay was later derived to describe the temporal consequence of that phase behavior.
- cmsp4kp8x042sjlss3oao3v2k← DEPENDS_ON
Bandwidth is operationally defined as the range of frequencies where a system's frequency response meets performance criteria (e.g., -3dB points). Remove frequency-response and bandwidth ceases to have any operational definition — it is not a standalone concept but a derived measure of frequency-response shape.
- cmsph7xoa05c2jlssqqltacp9← INSTANCE_OF
phase-response is a specific kind of frequency-response: while frequency-response broadly describes how a system modifies signal amplitudes across frequencies, phase-response specifically describes the phase shift component. A competent speaker would call phase-response a frequency response.
Record identity
- Created
- Aug 11, 2026, 9:27 PM UTC
- Content hash
- 353445a95c5fd204a5353a1a0823b00fc30d8cb534197ac5d26142a4370a985c