phased.RISReflector

Reconfigurable intelligent surface (RIS) reflector

Since R2025a

Description

phased.RISReflector creates a narrowband rectangular Reconfigurable Intelligent Surface (RIS) reflector System object™. The object reflects narrowband signals in specified directions using a RIS surface.

To create and use a phased.RISReflector System object:

1. Create the phased.RISReflector object and set its properties.

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

To learn more about how System objects work, see What Are System Objects?

Creation

Syntax

reflector = phased.RISReflector

reflector = phased.RISReflector(Name=Value)

Description

reflector = phased.RISReflector creates a phased.RISReflector System object, reflector, with default property values.

reflector = phased.RISReflector(Name=Value) creates a phased.RISReflector System object with each specified property Name set to the specified Value.

Specify optional pairs of arguments as Name1=Value1,...,NameN=ValueN, where Name is the argument name and Value is the corresponding value. Name-value arguments must appear after other arguments, but the order of the pairs does not matter.

Properties

Unless otherwise indicated, properties are nontunable, which means you cannot change their values after calling the object. Objects lock when you call them, and the release function unlocks them.

If a property is tunable, you can change its value at any time.

For more information on changing property values, see System Design in MATLAB Using System Objects.

Surface — RIS surface

phased.RectangularRIS System object with default properties (default) | phased.RectangularRIS System object

RIS surface, specified as a phased.RectangularRIS System object. By default, the RIS surface has default phased.RectangularRIS properties.

OperatingFrequency — Operating frequency (Hz)

300e6 (default) | positive scalar

Operating frequency, specified as a positive scalar. Units are in Hz.

Data Types: double

PropagationSpeed — Propagation speed (m/s)

physconst("LightSpeed") (default) | positive scalar

Propagation speed, specified as a positive scalar. Units are in meters/second.

Example: 3e8

Data Types: double

Usage

Syntax

resp = reflector(X,angin,angout,w)

Description

resp = reflector(X,angin,angout,w) reflects signals, X, coming from incident directions specified by angin and towards reflection directions specified by angout. w represents the weights applied to each element of the surface.

Input Arguments

X — Incident signals

complex-valued M-column matrix

Incident signal, specified as a complex-valued M-column matrix. Matrix columns represent independent signals arriving at the surface.

Data Types: double
Complex Number Support: Yes

angin — Incident angles (degrees)

real-valued length-M vector | real-valued 2-by-M matrix

Incident angles of signals, specified as a real-valued length-M vector or real-valued 2-by-M matrix. M is the number of incident angles. If angin is a matrix, each column specifies an incident direction in the form of an [AzimuthAngle;ElevationAngle] pair. If angin is a vector, it represents only the azimuth angle. The corresponding elevation angles are zero. Units are in degrees.

Data Types: double

angout — Reflected angles (degrees)

real-valued length-M vector | real-valued 2-by-M matrix

Reflected angles of signals, specified as a real-valued length-M vector or real-valued 2-by-M matrix. M is the number of reflected angles. angout must have the same size and dimensions as angin. If angin is a matrix, each column specifies an incident direction in the form of an [AzimuthAngle;ElevationAngle] pair. If angin is a vector, it represents only the azimuth angle. The corresponding elevation angles are zero. Units are in degrees.

Data Types: double

w — RIS array weights

complex-valued length-P column vector

RIS array weights, specified as a complex-valued column vector. The number of entries in w must be the same as the number of array elements specified in the Size property of the RIS Surface.

Data Types: double
Complex Number Support: Yes

Output Arguments

Y — Reflected signals from RIS

complex-valued M-column matrix

Reflected signals from RIS, returned as a complex-valued M-column matrix. Each column represents a different reflected signal from the surface.

Object Functions

To use an object function, specify the System object as the first input argument. For example, to release system resources of a System object named obj, use this syntax:

release(obj)

Common to All System Objects

step	Run System object algorithm
release	Release resources and allow changes to System object property values and input characteristics
reset	Reset internal states of System object

Examples

Scattered Signal from 25-by-25 RIS

Compute a signal scattered from a 25-by-25 Reconfigurable Intelligent Surface (RIS). The incident angle to the surface is${10}^{°}$ in azimuth and the reflected direction is ${-10}^{°}$in azimuth. Apply uniform weights to the RIS. RIS elements are half-wavelength apart.

fc = 300e6;
c = physconst("LightSpeed");
lambda = c/fc;
d = 0.5*lambda;

Create a rectangular RIS surface from cosine antenna elements.

ris = phased.RectangularRIS(...
    UnitCell=phased.CosineAntennaElement(CosinePower=2), ...
    Size=[25 25],Spacing=[d,d]);

Create the RIS reflector from the surface.

reflector = phased.RISReflector(Surface=ris);

Reflect a random signal.

x = randn(50,1);

Apply uniform weights to the array elements.

w = ones(getNumElements(reflector.Surface),1);

Display the array response.

y = reflector(x,[10;0],[-10;0],w)

y = 50×1
103 ×

    0.3161
    1.0781
   -1.3279
    0.5069
    0.1874
   -0.7688
   -0.2549
    0.2014
    2.1037
    1.6281
   -0.7936
    1.7842
    0.4264
   -0.0371
    0.4202
      ⋮

pattern(ris,fc,[10;0],-45:45,-45:45)

Extended Capabilities

C/C++ Code Generation
Generate C and C++ code using MATLAB® Coder™.

Version History

Introduced in R2025a