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)
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 in X
.
Each column of Y
contains the output of the corresponding
element in response to all the signals in X
.
If Wavefront
has the value 'Unspecified'
,
each collecting element collects only one impinging signal from X
.
Each column of Y
contains the output of the corresponding
element in response to the corresponding column of X
.
The 'Unspecified'
option is available when the Sensor
property
of H
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 

Collector object.  

Arriving signals. Each column of
 

Incident directions of signals, specified as a tworow 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 length2 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. 

Collected signals. Each column of 
Construct a 4element uniform linear array. The array operating frequency is 1 GHz. The array element spacing is half the operating frequency wavelength. Model the collection of a 200Hz sine wave incident on the array from 45 degrees azimuth, 10 degrees elevation from the far field.
fc = 1e9; lambda = physconst('LightSpeed')/fc; hULA = phased.ULA('NumElements',4,'ElementSpacing',lambda/2); t = linspace(0,1,1e3); x = cos(2*pi*200*t)'; % construct the collector object. hc = phased.Collector('Sensor',hULA,... 'PropagationSpeed',physconst('LightSpeed'),... 'Wavefront','Plane','OperatingFrequency',fc); % incident angle is 45 degrees azimuth, 10 degrees elevation incidentangle = [45;10]; % collect the incident waveform at the ULA receivedsig = step(hc,x,incidentangle);
If the Wavefront
property value is 'Plane'
, phased.Collector
collects
each plane wave signal using the phase approximation of the time delays
across collecting elements in the far field.
If the Wavefront
property value is 'Unspecified'
, phased.Collector
collects
each channel independently.
For further details, see [1].
[1] Van Trees, H. Optimum Array Processing. New York: WileyInterscience, 2002.