step
System object: phased.WidebandCollector
Namespace: phased
Collect signals
Syntax
Y = step(H,X,ANG)
Y = step(H,X,ANG,LAXES)
Y = step(H,X,ANG,WEIGHTS)
Y = step(H,X,ANG,STEERANGLE)
Y = step(H,X,ANG,LAXES,WEIGHTS,STEERANGLE)
Description
Note
Starting in R2016b, instead of using the step
method to perform the operation defined by the System object™, you can call the object with arguments, as if it were a function. For example, y = step(obj,x)
and y = obj(x)
perform equivalent operations.
collects
signals Y
= step(H
,X
,ANG
)X
arriving from directions ANG
.
The collection process depends on the Wavefront
property
of H
, as follows:
If
Wavefront
has the value'Plane'
, each collecting element collects all the far field signals inX
. Each column ofY
contains the output of the corresponding element in response to all the signals inX
.If
Wavefront
has the value'Unspecified'
, each collecting element collects only one impinging signal fromX
. Each column ofY
contains the output of the corresponding element in response to the corresponding column ofX
. The'Unspecified'
option is available when theSensor
property ofH
does not contain subarrays.
uses Y
= step(H
,X
,ANG
,LAXES
)LAXES
as
the local coordinate system axes directions. This syntax is available
when you set the EnablePolarization
property
to true
.
uses Y
= step(H
,X
,ANG
,WEIGHTS
)WEIGHTS
as
the weight vector. This syntax is available when you set the WeightsInputPort
property
to true
.
uses Y
= step(H
,X
,ANG
,STEERANGLE
)STEERANGLE
as
the subarray steering angle. This syntax is available when you configure H
so
that H.Sensor
is an array that contains subarrays
and H.Sensor.SubarraySteering
is either 'Phase'
or 'Time'
.
combines
all input arguments. This syntax is available when you configure Y
= step(H
,X
,ANG
,LAXES
,WEIGHTS
,STEERANGLE
)H
so
that H.WeightsInputPort
is true
, H.Sensor
is
an array that contains subarrays, and H.Sensor.SubarraySteering
is
either 'Phase'
or 'Time'
.
Note
The object performs an initialization the first time the object is executed. This
initialization locks nontunable properties
and input specifications, such as dimensions, complexity, and data type of the input data.
If you change a nontunable property or an input specification, the System object issues an error. To change nontunable properties or inputs, you must first
call the release
method to unlock the object.
Input Arguments
|
Collector object. | ||||||
|
Arriving signals. Each column of
| ||||||
|
Incident directions of signals, specified as a two-row matrix.
Each column specifies the incident direction of the corresponding
column of | ||||||
|
Local coordinate system. | ||||||
|
Vector of weights. Default: | ||||||
|
Subarray steering angle, specified as a length-2 column vector. The vector has the form [azimuth; elevation], in degrees. The azimuth angle must be between –180 and 180 degrees, inclusive. The elevation angle must be between –90 and 90 degrees, inclusive. |
Output Arguments
|
Collected signals. Each column of |
Examples
Algorithms
If the Wavefront
property value is 'Plane'
, phased.WidebandCollector
does
the following for each plane wave signal:
Decomposes the signal into multiple subbands.
Uses the phase approximation of the time delays across collecting elements in the far field for each subband.
Regroups the collected signals in all the subbands to form the output signal.
If the Wavefront
property value is 'Unspecified'
, the
object collects each channel independently.
For further details, see [1].
References
[1] Van Trees, H. Optimum Array Processing. New York: Wiley-Interscience, 2002.