EngeePhased.ReplicatedSubarray

A phased antenna array formed from replicated antenna subarrays.

*Library: EngeePhased

Description

The EngeePhased.ReplicatedSubarray system object represents a phased antenna array containing copies of antenna sub-arrays. Antenna sub-arrays are created by replicating one given antenna array.

To get the response of the antenna sub-arrays, follow the steps below:

Identify and configure your phased array containing replicated antenna sublattices.
Call the step! method to compute the response of the antenna sublattices according to the EngeePhased.ReplicatedSubarray properties. The step behaviour is specific to each object in the toolbar.

The EngeePhased.ReplicatedSubarray system object can also be used as the value of the SensorArray or Sensor properties of objects performing beamforming, steering and other operations.

Instead of using the step! method to perform an operation defined by a 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.

Constructor

H =EngeePphased.ReplicatedSubarray creates a replicated antenna subarray system object, H. This object represents an antenna array containing copies of the antenna sublattice.
H = EngeePphased.ReplicatedSubarray(Name,Value) creates a replicated antenna sublattice object, H, with each specified Name (name) property set to the specified Value (value). You can specify additional arguments as a name-value pair in any order (Name1,Value1,…,NameN,ValueN).

Properties

*Subarray.

Antenna sublattice for replication

Specify the antenna array that is used to form the antenna sublattice. The antenna sublattice must be an EngeePhased.ULA, EngeePhased.URA or EngeePhased.ConformalArray object.

By default: EngeePhased.ULA with property values by default

Layout.

Location of antenna sub-grids

Specify the layout of the replicated antenna sub-trees as Rectangular or Custom.

*By default: Rectangular.

*GridSize.

Rectangular grid size

Specify the size of the rectangular grid as a single positive integer or a vector of rows of 1 by 2 positive integers. This property is only applicable if the Layout property is set to Rectangular.

If the GridSize property is set to scalar, the antenna array has the same number of antenna sub-grids in each row and each column.

If the GridSize property is set to a vector value of 1 by 2, then the vector is [NumberOfRows, NumberOfColumns]. The NumberOfRows element is the number of antenna sub-grids along each column. The NumberOfColumns element is the number of antenna sub-grids along each row. A row is along the local y axis and a column is along the local z axis.

This figure shows how a 3 by 2 URA antenna sublattice is replicated when the [1,2] value of the GridSize property is set.

object engee phased replicated subarray

By default: [1,2]

GridSpacing.

Spacing between rectangular grids

Specify the distance between rectangular grids of antenna sub-grids as a positive real scalar, a vector of 1 by 2 rows or Auto. This property is only applicable if the Layout property is set to 'Rectangular'. The units of grid spacing are m.

If the GridSpacing property is set to scalar, the row and column spacing is the same.

If the GridSpacing property is set to a vector of length 2 rows, it is [SpacingBetweenRows, SpacingBetweenColumn]. The SpacingBetweenRows element specifies the row spacing along the column. The SpacingBetweenColumn element specifies the distance between columns in a row.

If the GridSpacing property is set to Auto, replication preserves the spacing between elements in both row and column. This value is only available if the EngeePhased.ULA or EngeePhased.URA object is used as an antenna sublattice.

By default: Auto.

SubarrayPosition

Antenna sub-grid positions in the user grid

Specify the positions of the antenna sub-arrays in the custom mesh as a 3 by N matrix, where N is the number of antenna sub-arrays in the antenna array. Each column of the matrix represents the position of one antenna sub-grid in the local coordinate system of the antenna array, in metres, in the form [x; y; z].

This property is applied if the Layout property is set to Custom.

*By default: [0 0; -0,5 0,5; 0 0]

SubarrayNormal

Normal directions of antenna subgrids in a custom grid

Specify the directions of the normals of the antenna sub-arrays in an antenna array as a 2 by N matrix, where N is the number of antenna sub-arrays in the antenna array. Each column of the matrix specifies the direction of the normal of the corresponding antenna sub array in the form [azimuth; elevation]. Each angle is given in degrees and is defined in a local coordinate system.

The SubarrayPosition and SubarrayNormal properties can be used to represent any arrangement in which pairs of antenna sublattices are distinguished by certain transformations. These transformations may include translation, azimuth rotation, and elevation rotation. However, transformations that require rotation with respect to the normal cannot be used.

This property applies if the Layout property is set to Custom.

By default: [0 0; 0 0]

SubarraySteering.

Antenna sublattice control method

Specify the antenna sublattice control method as None, Phase, Time or Custom.

If the SubarraySteering property is set to Phase, phase shift is used to control the antenna sublattice. Use the STEERANG argument of the step! method to determine the control direction.

If the SubarraySteering property is set to Time, the antenna sublattice is controlled using time delays. Use the STEERANG argument of the step! method to define the control direction.

If the SubarraySteering property is set to Custom, the antenna sublattices will be managed by setting independent weighting factors for all elements in each sublattice. Use the WS argument of the step! method to define the weighting factors for all antenna sublattices.

By default: None.

PhaseShifterFrequency

Antenna sublattice phase shifter frequency

Specify the operating frequency of the phase shifters performing antenna sublattice control as a positive scalar.

The unit of measurement is Hz.

This property is applied when the SubarraySteering property is set to Phase.

*By default: 3e8

NumPhaseShifterBits.

Number of phase shift quantisation bits

The number of bits used to quantise the phase shift component of the weighting coefficients of the beamforming vector or control vector. Set as a non-negative integer.

A value of zero means that no quantisation is performed.

By default: 0

Methods

Common for all system objects

step!

Start the system object algorithm

release!

Allow changing the value of the system object property

reset!

Reset internal states of system object