The HeterogeneousConformalArray object constructs
a conformal array from a heterogeneous set of antenna elements. A
heterogeneous array is an array in which the antenna or microphone
elements may be of different kinds or have different properties. An
example would be an array of elements each having different antenna
patterns. A conformal array can have elements
in any position pointing in any direction.

To compute the response for each element in the array for specified
directions:

Define and set up your conformal array. See Construction.

Call step to
compute the response according to the properties of phased.HeterogeneousConformalArray.
The behavior of step is specific to each object in
the toolbox.

Construction

H = phased.HeterogeneousConformalArray creates
a heterogeneous conformal array System object™, H.
This object models a heterogeneous conformal array formed with sensor
elements whose pattern may vary from element to element.

H = phased.HeterogeneousConformalArray(Name,Value) creates
object, H, with each specified property Name
set to the specified Value. You can specify additional name-value
pair arguments in any order as (Name1,Value1,...,NameN,ValueN).

Properties

ElementSet

Set of elements used in the array

Specify the set of different elements used in the sensor array
as a row MATLAB cell array. Each member of the cell array contains
an element object in the phased package. Elements specified in the ElementSet property
must be either all antennas or all microphones. In addition, all specified
antenna elements should have same polarization capability. Specify
the element of the sensor array as a handle. The element must be an
element object in the phased package.

Default: One cell containing one isotropic antenna element

ElementIndices

Elements location assignment

This property specifies the mapping of elements in the array.
The property assigns elements to their locations in the array using
the indices into the ElementSet property. The
value of ElementIndices must be an length-N row
vector. In this vector, N represents the number
of elements in the array. The values in the vector specified by ElementIndices should
be less than or equal to the number of entries in the ElementSet property.

Default: [1 2 2 1]

ElementPosition

Element positions

ElementPosition specifies the positions
of the elements in the conformal array. The value of the ElementPosition property
must be a 3-by-N matrix, where N indicates
the number of elements in the conformal array. Each column of ElementPosition represents
the position, in the form [x; y; z] (in meters),
of a single element in the array's local coordinate system.
The local coordinate system has its origin at an arbitrary point.

Default: [0; 0; 0]

ElementNormal

Element normal directions

ElementNormal specifies the normal directions
of the elements in the conformal array. Angle units are degrees. The
value assigned to ElementNormal must be either
a 2-by-N matrix or a 2-by-1 column vector. The
variable N indicates the number of elements in
the array. If the value of ElementNormal is a
matrix, each column specifies the normal direction of the corresponding
element in the form [azimuth;elevation] with respect
to the local coordinate system. The local coordinate system aligns
the positive x-axis with the direction normal to
the conformal array. If the value of ElementNormal is
a 2-by-1 column vector, it specifies the pointing direction of all
elements in the array.

You can use the ElementPosition and ElementNormal properties
to represent any arrangement in which pairs of elements differ by
certain transformations. The transformations can combine translation,
azimuth rotation, and elevation rotation. However, you cannot use
transformations that require rotation about the normal.

Default: [0; 0]

Taper

Element taper or weighting

Element tapering specified as a complex-valued scalar or a complex-valued
1-by-N row vector. N is the
number of elements in the array as determined by the size of the ElementIndices property.
Tapers, also known as weights, are applied to each sensor element
in the sensor array and modify both the amplitude and phase of the
received data. If 'Taper' is a scalar, the same
weights are applied to each element. If 'Taper' is
a vector, each weight is applied to the corresponding sensor element.

Construct an 8-element heterogeneous uniform
circular array (UCA). Four of the elements have a cosine pattern with
a power of 1.6. The remaining four have a cosine pattern with a power
of 1.5. Plot its response as a function of elevation angle. Assume
a 1 GHz operating frequency. The wave propagation speed is the speed
of light.