Engee documentation

EngeePhased.ConformalArray

Conformal phased array antenna.

Library

EngeePhased

Description

System object EngeePhased.ConformalArray simulates a conformal antenna array. A conformal antenna array may contain elements positioned in arbitrary positions and oriented in any direction.

To create and use a conformal antenna array, follow these steps:

  1. Create an object EngeePhased.ConformalArray and set its properties.

  2. Call the object with arguments as if it were a function.

To learn more about how to work with system objects, see Engee System Objects.

Syntax

Creation

  • array = EngeePhased.ConformalArray() — creates a conformal antenna array with default property values. The object simulates a conformal antenna array consisting of identical sensor elements.

  • array = EngeePhased.ConformalArray(Name=Value) — creates a conformal antenna array with specified properties in the form of a pair Name=Value, where Name — the name of the property, and Value — the appropriate value. You can specify multiple pairs «name-value» the order of the pairs does not matter. Unspecified properties retain their default values.

    Example:

    H = EngeePhased.ConformalArray(ElementNormal=[2; 4])

Using

  • RESP = array(FREQ,ANG) — returns the radiation pattern RESP of the antenna array elements at the operating frequencies FREQ in the directions ANG.

Arguments

Input arguments

FREQ — the operating frequencies of the antenna array

+ vector is a string of length L

Details

The operating frequencies of the antenna array, set as a real vector, are strings of length containing positive numbers. Typical values are in the range specified by the properties of the FrequencyRange or FrequencyVector element, depending on the type of element in the antenna array. The element has a zero radiation pattern at frequencies outside this range.

The units of measurement are Hz.

Типы данных

Float64

ANG — azimuth angle and angle of the radiation pattern

+ vector is a string of length M | the 2 by M matrix

Details

The directions of the radiation pattern, specified as a real vector, are strings of length or a real matrix on .

If ANG is a matrix, then each column defines a direction in the form [azimuth; elevation]. The azimuthal angle should be in the range of −180° before 180° inclusive. The angle of the seat should be in the range of −180° before 180° inclusive.

If ANG is a string vector, each element sets the azimuth angle of the direction. In this case, the corresponding seat angle is assumed to be .

The units of measurement are degrees.

Типы данных

Float64

Output arguments

RESP — antenna array radiation pattern

+ a complex array of N by M by L

Details

The radiation pattern of the antenna array, returned as a complex array of the size on on , where — the number of elements in the antenna array, — the number of angles specified in ANG, — the number of frequencies specified in FREQ.

Features

# Element — element of the antenna array

+ IsotropicAntennaElement (by default) | the system object of the antenna array element

Details

An element of the antenna array, defined as a system object antenna, microphone or converter.

By default, it is used EngeePhased.IsotropicAntennaElement with default properties.

# ElementPosition — positions of the antenna array elements

+ [0, 0, 0] (by default) | the 3 by N matrix

Details

The position of the elements in the conformal antenna array, given as a real matrix on , where — the number of elements in the conformal antenna array.

Each column of ElementPosition represents a position in the form [x, y, z] one element in the local coordinate system of the antenna array. The origin of the local coordinate system can be at any point.

The units of measurement are m.

Default value [0, 0, 0] This property is set by a single element at the origin of the local coordinate system.

# ElementNormal — directions of the elements' normals

+ [0, 0] (by default) | the 2 by N matrix | column vector 2 by 1

Details

The directions of the normals of the elements in the conformal antenna array, given as a real column vector on or matrices on , where  — the number of elements in the antenna array.

If the value of ElementNormal is a matrix, then each column specifies the direction of the normals of the corresponding element in the form [azimuth,elevation] relative to the local coordinate system. The local coordinate system aligns the positive axis in the direction of the normal to the conformal antenna array.

If the value of ElementNormal is a column vector on , then the same direction is set for all elements of the antenna array.

The units of measurement are degrees.

Properties ElementPosition and ElementNormal can be used to represent any arrangement in which pairs of elements differ by certain transformations. These transformations can combine displacement, azimuthal rotation, and elevation rotation. However, you cannot use transformations that require rotation around the normal.

# Taper — complex weighting coefficients for amplitude weighing

+ 1 (by default) | the complex scalar | A complex vector is a row of 1 by N | The complex column vector is N by 1

Details

Complex weighting coefficients for antenna array elements, given as a complex scalar, a complex string vector on or a complex column vector on , where It represents the number of antenna array elements. Weighting factors are applied to each antenna element of the antenna array and change the amplitude and phase of the received data.

  • If Taper is a scalar, the same coefficient value is applied to all elements of the antenna array.

  • If Taper is a vector, its own coefficient value is applied to each element of the antenna array.

Methods

Common to all system objects

step!

Running the system object operation algorithm

release!

Permission to change the value of a system object property

reset!

Resetting the internal states of a system object

Literature

  1. Josefsson, L. and P. Persson. Conformal Array Antenna Theory and Design. Piscataway, NJ: IEEE Press, 2006.

  2. Van Trees, H. Optimum Array Processing. New York: Wiley-Interscience, 2002.