CustomMicrophoneElement object creates
a custom microphone element.
To compute the response of the microphone element for specified directions:
Define and set up your custom microphone element. See Construction.
compute the response according to the properties of
The behavior of
step is specific to each object in
Starting in R2016b, instead of using the
H = phased.CustomMicrophoneElement creates
a custom microphone system object,
H, that models
a custom microphone element.
H = phased.CustomMicrophoneElement( creates
a custom microphone object,
H, with each specified
property set to the specified value. You can specify additional name-value
pair arguments in any order as (
Operating frequency vector
Specify the frequencies in hertz where the frequency responses of element are measured as a vector. The elements of the vector must be increasing. The microphone element has no response outside the specified frequency range.
Specify the frequency responses in decibels measured at the
frequencies defined in the
Polar pattern measuring frequencies
Specify the measuring frequencies in hertz of the polar patterns
as a row vector of length M. The measuring frequencies must be within
the frequency range specified in the
Polar pattern measuring angles
Specify the measuring angles in degrees of the polar patterns as a row vector of length N. The angles are measured from the central pickup axis of the microphone, and must be between –180 and 180, inclusive.
Specify the polar patterns of the microphone element as an M-by-N
matrix. M is the number of measuring frequencies specified in the
Default: An omnidirectional pattern with 0 dB response everywhere
|clone||Create omnidirectional microphone object with same property values|
|directivity||Directivity of custom microphone element|
|getNumInputs||Number of expected inputs to step method|
|getNumOutputs||Number of outputs from step method|
|isLocked||Locked status for input attributes and nontunable properties|
|pattern||Plot custom microphone element directivity and patterns|
|patternAzimuth||Plot custom microphone element directivity or pattern versus azimuth|
|patternElevation||Plot custom microphone element directivity or pattern versus elevation|
|plotResponse||Plot response pattern of microphone|
|release||Allow property value and input characteristics changes|
|step||Output response of microphone|
Create a custom cardioid microphone, and calculate the microphone response at 500, 1500, and 2000 Hz in two directions: (0,0) azimuth and elevation, and (40,50) azimuth and elevation.
sCustMic = phased.CustomMicrophoneElement; sCustMic.PolarPatternFrequencies = [500 1000]; sCustMic.PolarPattern = mag2db([... 0.5+0.5*cosd(sCustMic.PolarPatternAngles);... 0.6+0.4*cosd(sCustMic.PolarPatternAngles)]); resp = step(sCustMic,[500 1500 2000],[0 0; 40 50]')
resp = 1.0000 1.0000 1.0000 0.7424 0.7939 0.7939
The total response of a custom microphone element is a combination
of its frequency response and spatial response.
both responses using nearest neighbor interpolation and then multiplies
them to form the total response. When the
value is nonscalar, the object specifies multiple polar patterns.
In this case, the interpolation uses the polar pattern that is measured
closest to the specified frequency.