# Linear filter

**linearlinear filtersfilterfilter maskLTIfiltersfrequency responseslinear analogue passive filterstransfer function**

Linear filters process time-varying input signals to produce output signals, subject to the constraint of linearity.wikipedia

109 Related Articles

### Filter (signal processing)

**filterfiltersfiltering**

Most filters implemented in analog electronics, in digital signal processing, or in mechanical systems are classified as causal, time invariant, and linear signal processing filters.

linear or non-linear

### Linearity

**linearlinearlycomplex linear**

Linear filters process time-varying input signals to produce output signals, subject to the constraint of linearity.

Others are linear filters, linear regulators, and linear amplifiers in general.

### Equalization (audio)

**equalizationequalizerEQ**

An equalization filter is not designed to fully pass or block any frequency, but instead to gradually vary the amplitude response as a function of frequency: filters used as pre-emphasis filters, equalizers, or tone controls are good examples.

In sound recording and reproduction, equalization is the process commonly used to alter the frequency response of an audio system using linear filters.

### Bessel filter

**BesselBessel electronic filterstime-delay networks**

A Bessel filter (not shown) has an even poorer transition in the frequency domain, but maintains the best phase fidelity of a waveform.

In electronics and signal processing, a Bessel filter is a type of analog linear filter with a maximally flat group/phase delay (maximally linear phase response), which preserves the wave shape of filtered signals in the passband.

### Matched filter

**matched filteringmatched-filteringNorth filters**

They can easily be designed to give a matched filter for any arbitrary pulse shape.

The matched filter is the optimal linear filter for maximizing the signal-to-noise ratio (SNR) in the presence of additive stochastic noise.

### Wiener filter

**WienerWiener–Kolmogorov filterWiener filtering**

Wiener filter

In signal processing, the Wiener filter is a filter used to produce an estimate of a desired or target random process by linear time-invariant (LTI) filtering of an observed noisy process, assuming known stationary signal and noise spectra, and additive noise.

### Prototype filter

**prototypeimpedance scalingfrequency transformations**

Prototype filter

They are most often seen in regard to electronic filters and especially linear analogue passive filters.

### Gabor filter

**Gabor filtersGabor filtersGabor model**

Gabor filter

In image processing, a Gabor filter, named after Dennis Gabor, is a linear filter used for texture analysis, which means that it basically analyzes whether there are any specific frequency content in the image in specific directions in a localized region around the point or region of analysis.

### Digital biquad filter

**2-pole IIR filter sectionsBiquad filterbiquad sections**

Typically digital IIR filters are designed as a series of digital biquad filters.

In signal processing, a digital biquad filter is a second-order recursive linear filter, containing two poles and two zeros.

### Audio filter

**filterfiltersfiltering**

An equalization filter is not designed to fully pass or block any frequency, but instead to gradually vary the amplitude response as a function of frequency: filters used as pre-emphasis filters, equalizers, or tone controls are good examples.

Linear filter

### Filter design

**filter theorydesigndesigned**

Filter design

The design of linear analog filters is for the most part covered in the linear filter section.

### Analogue electronics

**analoganalog circuitanalogue**

Most filters implemented in analog electronics, in digital signal processing, or in mechanical systems are classified as causal, time invariant, and linear signal processing filters.

### Digital signal processing

**DSPsignal processingdigital signal processing (DSP)**

Most filters implemented in analog electronics, in digital signal processing, or in mechanical systems are classified as causal, time invariant, and linear signal processing filters.

### Causality

**causalcausationcause and effect**

### Statistics

**statisticalstatistical analysisstatistician**

The general concept of linear filtering is also used in statistics, data analysis, and mechanical engineering among other fields and technologies.

### Data analysis

**data analyticsanalysisdata analyst**

The general concept of linear filtering is also used in statistics, data analysis, and mechanical engineering among other fields and technologies.

### Mechanical engineering

**mechanical engineermechanicalmechanical engineers**

The general concept of linear filtering is also used in statistics, data analysis, and mechanical engineering among other fields and technologies.

### Linear time-invariant system

**linear time-invariantLTIlinear time invariant**

A linear time-invariant (LTI) filter can be uniquely specified by its impulse response h, and the output of any filter is mathematically expressed as the convolution of the input with that impulse response.

### Impulse response

**impulseImpulse Response Functionsimpulse-response function.**

A linear time-invariant (LTI) filter can be uniquely specified by its impulse response h, and the output of any filter is mathematically expressed as the convolution of the input with that impulse response.

### Frequency response

**frequency response functionfrequencyresponse function**

The frequency response, given by the filter's transfer function H(\omega), is an alternative characterization of the filter.

### Transfer function

**transfertransfer characteristicchannel transfer function**

The frequency response, given by the filter's transfer function H(\omega), is an alternative characterization of the filter.

### Phase (waves)

**phasephase shiftout of phase**

Typical filter design goals are to realize a particular frequency response, that is, the magnitude of the transfer function |H(\omega)|; the importance of the phase of the transfer function varies according to the application, inasmuch as the shape of a waveform can be distorted to a greater or lesser extent in the process of achieving a desired (amplitude) response in the frequency domain.

### Signal

**signalselectrical signalelectrical signals**

The frequency response may be tailored to, for instance, eliminate unwanted frequency components from an input signal, or to limit an amplifier to signals within a particular band of frequencies.

### Dirac delta function

**delta functionimpulsedirac delta**

An "impulse" in a continuous time filter means a Dirac delta function; in a discrete time filter the Kronecker delta function would apply.

### Discrete time and continuous time

**discrete-timediscrete timecontinuous-time**

An "impulse" in a continuous time filter means a Dirac delta function; in a discrete time filter the Kronecker delta function would apply.