Does phased.RotateArray still exist?

I am looking to build a LHCP (left hand circular polarised) and RHCP(right hand circular polarised) antenna within matlab. My logic is to create two short dipole element and then place them 90 degree out of phase. Thus, I am looking to rotate one of the array such that it would rotate one of the short dipole element.

I have attached my code with it, please help me out.

function cpAntenna = createCircularPolarizedAntenna(antennaType, freq)
    % Define two orthogonal linear antennas
    antenna1 = phased.ShortDipoleAntennaElement('AxisDirection','Z','FrequencyRange',[1e9 10e9]);
    antenna2 = phased.ShortDipoleAntennaElement('AxisDirection','Z','FrequencyRange',[1e9 10e9]);
    antenna2 = phased.RotateArray('Array',antenna2,'Z',90); % Rotate 90 degrees for orthogonality

    % Determine phase shift based on antenna type (RHCP or LHCP)
    if antennaType == "RHCP"
        phaseShift = [0, 90]; % 90-degree lag for RHCP
    elseif antennaType == "LHCP"
        phaseShift = [0, -90]; % 90-degree lead for LHCP
    else
        error('Invalid antenna type. Choose "RHCP" or "LHCP".');
    end

Also if there is anybody that has any better ideas of building a LHCP and RHCP in matlab, feel free to help out.

[Tianchu Lu]

I have initially done it with a phased.RotateArray, I thought I seen it somewhere. But however, Matlab itself is not liking it at all, I was wondering if there is any other in built functions that is similar?

Thanks

[Steven Lord]

What does "is not liking it at all" mean in this context?

• Do you receive warning and/or error messages? If so the full and exact text of those messages (all the text displayed in orange and/or red in the Command Window) may be useful in determining what's going on and how to avoid the warning and/or error.
• Does it do something different than what you expected? If so, what did it do and what did you expect it to do?
• Did MATLAB crash? If so please send the crash log file (with a description of what you were running or doing in MATLAB when the crash occured) to Technical Support so we can investigate.

[Tianchu Lu]

Hi Steven,

Many thanks for your reply, this is the full and exact text that I am getting when I enter the function RotateArray. I dont think the function exist any more, please point out that anything that i have done wrong.

Thanks

Answer 1

[Sanchari]

Hi Tianchu,

I understand that you are trying to build a LHCP and RHCP antenna with MATLAB using Phased Array System Toolbox.

The error message here is because ‘phased.RotateArray’ is not a valid function or class in MATLAB's Phased Array System Toolbox. Instead, you can use the ‘phased.CrossedDipoleAntennaElement’ to achieve the same results.

You can refer to the example given in the following MathWorks Documentation which talks about using the Crossed Dipole Antenna Element system object within the toolbox, https://www.mathworks.com/help/phased/ug/cross-dipole-antenna-element.html

Please refer to the following links for further information on:

1. Dipole Antennas (MathWorks Documentation): https://www.mathworks.com/help/antenna/dipole-antennas.html
2. Crossed-Dipole (Turnstile) Antenna and Array (MathWorks Documentation): https://www.mathworks.com/help/antenna/ug/crossed-dipole-turnstile-antenna-and-array.html
3. Field Analysis of antenna Polarization (MathWorks Documentation): https://www.mathworks.com/help/antenna/ug/field-analysis.html#bup0mtl
4. Crossed Dipole Antenna Polarization (ML Answer): https://www.mathworks.com/matlabcentral/answers/1822873-crossed-dipole-antenna-polarization?s_tid=srchtitle
5. Phased Array System Overview (MathWorks Documentation): https://www.mathworks.com/help/phased/gs/system-overviews.html
6. Linear and Circular Polarization (MathWorks Documentation): https://www.mathworks.com/help/phased/ug/polarized-fields.html
7. Rotate elements in phase.ConformalArray (ML Answer): https://www.mathworks.com/support/search.html/answers/376763-rotate-elements-in-phase-conformalarray.html?fq%5B%5D=asset_type_name:answer&fq%5B%5D=category:phased/array-geometries-and-analysis&page=1

I hope this information is helpful to you!

[Tianchu Lu]

Thank you solving this answer! Really appreciate