Engee documentation

EngeePhased.URA

Uniform rectangular phased array antenna (URA).

Library

EngeePhased

Description

System object EngeePhased.URA simulates a uniform rectangular antenna array (URA).

To create and use an URA, follow these steps:

  1. Create an object EngeePhased.URA 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

  • ura = EngeePhased.URA() — creates an URA with default property values. . The elements of the URA are located in the plane in the form of a rectangular grid. The maximum of the antenna array pattern is directed along the positive axis .

  • ura = EngeePhased.URA(Name=Value) — creates an URA with the specified properties as 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:

    ura = EngeePhased.URA(Taper=[2 0.2 1])

Using

  • RESP = ura(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 — operating frequencies of the antenna array

+ scalar | vector is a string of length L

Details

The operating frequencies of the antenna array, specified as a real positive scalar or 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 location

+ 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.

# Size — URA dimension

+ [2 2] (by default) | positive scalar | The vector of positive values is 1 by 2

Details

The URA dimension, defined as a vector of integers on or a single integer.

  • If Size is a vector on , then it has the form [NumberOfRows, NumberOfColumns].

  • If Size is a scalar, then URA has the same number of elements in each row and each column. For URA, the antenna array elements are indexed from top to bottom in the column and then in the following columns from left to right.

The picture shows the system object ura = EngeePhased.URA(Size=[3 2]) that is, the URA has three rows and two columns.

so ura

# ElementSpacing — the distance between the elements

+ [0.5 0.5] (by default) | positive scalar | The vector of positive values is 1 by 2

Details

The distance between the elements, specified as a positive scalar or vector of positive values on .

  • If ElementSpacing is a vector on , it has the form [SpacingBetweenRows,SpacingBetweenColumns].

  • If ElementSpacing is a scalar, then the distances between rows and columns are equal.

The units of measurement are m.

# Lattice — type of lattice

+ "Rectangular" (default) | "Triangular"

Details

Element Grid Type:

  • If the Lattice parameter is set to "Rectangular" all URA elements are aligned both in the direction of the rows and in the direction of the columns.

  • If the Lattice parameter is set to "Triangular", the elements in the even rows are shifted towards the positive direction of the row axis. The offset is half the distance between the elements in the row.

# ArrayNormal — the direction of the antenna array normal

+ "x" (by default) | "y" | "z"

Details

The direction of the lattice normal, set as one of the directions "x", "y" or "z".

The URA elements lie in a plane orthogonal to the direction of the UCA normal. The vectors of the maximum directions of the radiation pattern lie in the same plane and are directed radially from the origin.

"x" The elements of the rectangular antenna array lie in - planes. All the normal vectors of the elements are directed along the axis . This value is used by default.

"y"

The elements of a rectangular antenna array lie in a plane . The normal vectors of all elements are directed along the axis .

"z"

The elements of a rectangular antenna array lie on a plane . The normal vectors of all elements are directed along the axis .

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. Brookner, E., ed. Radar Technology. Lexington, MA: LexBook, 1996.

  2. Brookner, E., ed. Practical Phased Array Antenna Systems. Boston: Artech House, 1991.

  3. Mailloux, R. J. Phased Array Theory and Technology, Proceedings of the IEEE, Vol., 70, Number 3s, pp. 246—291.

  4. Mott, H. Antennas for Radar and Communications, A Polarimetric Approach. New York: John Wiley & Sons, 1992.

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