Engee documentation

EngeePhased.ULA

Uniform linear Phased array (ULA).

Library

EngeePhased

Description

System object EngeePhased.ULA simulates a uniform linear antenna array (uniform linear array, ULA).

To create and use an ULA, follow these steps:

  1. Create an object EngeePhased.ULA 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

  • ula = EngeePhased.ULA() — creates an ULA with default property values. The origin of the local coordinate system is the phase center of the antenna array. The positive axis — this is the direction normal to the antenna array, and the elements of the antenna array are located along the axis .

  • ula = EngeePhased.ULA(Name=Value) — creates a uniform ULA 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.

Using

  • RESP = ula(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.

# numElements — the number of grid elements

+ 5 (by default) | a positive integer

Details

The number of grid elements specified as a positive integer.

# ElementSpacing — the distance between the elements of the antenna array

+ 0.5 (by default) | positive scalar

Details

The distance between two adjacent ULA elements, specified as a positive scalar.

The units of measurement are m.

# ArrayAxis — ULA + axis "y" (by default) | "x" | "z"

Details

The ULA axis, defined as "x", "y" or "z".

The ULA elements are located along the selected axis of the coordinate system. The axis of the antenna array determines the direction along which the normal vectors of the elements are directed.

Value of the ArrayAxis property The direction of the normal of the lattice element

"x"

azimuth angle 90°, seat angle (axis )

"y" (by default)

azimuth angle , seat angle (axis )

"z"

azimuth angle , seat angle (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. Van Trees, H. Optimum Array Processing. New York: Wiley-Interscience, 2002.