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Antenna

Model antenna accounting for incident power wave (RX) and radiated power wave (TX)

  • Library:
  • RF Blockset / Circuit Envelope / Elements

  • Default antenna block

Description

Model an antenna using the Antenna block:

  • Convert a Simulink® input of an incident power wave vector into an RF Blockset™ voltage at the antenna ports.

  • Convert current at an RF Blockset antenna port to a Simulink output of a radiated power wave vector.

  • Introduce antenna impedance into an RF system.

By default, the antenna block is an isotropic radiator producing a Simulink output signal. For an isotropic radiator, specify the gain and impedance of the antenna in the block parameters. The Radiated carrier frequencies parameter is a set of carrier frequencies over-which the Antenna block creates the radiated power wave. For more information, see Radiated Wave and Incident Wave.

Ports

Input

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Receiving signal, specified as a scalar, vector matrix, or an array of size m-by-n-by-2.

Data Types: double

Output

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Transmitting signal, specified as a scalar, vector, matrix, or an array of size m-by-n-by-2

Data Types: double

Parameters

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Main

Antenna model, specified as one of the following:

  • Isotropic radiator

  • Antenna Designer

  • Antenna object

Note

To use Antenna Designer and Antenna object options you will need Antenna Toolbox™.

Open the Antenna Designer app from the Antenna Toolbox to create an antenna.

Dependencies

To enable this parameter, set the Source of antenna model to Antenna Designer.

Antenna element input from the workspace, specified as a single port antenna element created using the Antenna Toolbox. Analyze the antenna object in the workspace for at least one frequency before using it in the block.

Dependencies

To enable this parameter, set Source of antenna model to Antenna object.

Antenna gain, specified as real scalar or vector if you set units to dBi or positive scalar or vector if you set units are None. If the antenna gain is a vector, the vector length must be equal to the vector length of Incident carrier frequencies and Radiated carrier frequencies.

Dependencies

To enable this parameter, set Source of antenna model to Isotropic radiator and check Input incident wave or Output radiated wave or both

Input impedance, specified as a complex-valued scalar or vector in ohms. If the impedance is a vector, the vector length must be equal to the length of Incident carrier frequencies and Radiated carrier frequencies.

Dependencies

To enable this parameter, set Source of antenna model to Isotropic radiator.

Data Types: double
Complex Number Support: Yes

Select this parameter if you want to simulate a receiving antenna.

Select this parameter if you want a simulate a transmitting antenna.

Carrier frequencies for a receiving signal, specified as a nonnegative scalar in hertz or a row vector with each element unit in hertz. If the value of Antenna gain or Impedance is a vector, then the values of Incident carrier frequencies and Radiated carrier frequencies must be identical.

Dependencies

To enable this parameter, select Input incident wave.

Carrier frequencies for a transmitting signal, specified as a nonnegative scalar in hertz or a row vector with each element unit in hertz. If the value of Antenna gain or Impedance is a vector, then the values of Incident carrier frequencies and Radiated carrier frequencies must be identical.

Dependencies

To enable this parameter, select Output radiated wave.

Azimuth and elevation angles towards which the output signal power wave radiates, specified as a finite real row vector of length two with each element unit in degrees or radians.

Dependencies

To enable this parameter, set Source of antenna model to Antenna Designer or Antenna object and select Output radiated wave.

Azimuth and elevation angles towards which the input signal power wave arrives, specified as a finite real row vector of length two with each element unit in degrees or radians.

Dependencies

To enable this parameter, set Source of antenna model to Antenna Designer or Antenna object and select Input incident wave.

Select this parameter to simulate thermal noise in the antenna due to the real part of the impedance see at the antenna terminals. You must select Simulate noise in the Configuration block also.

Select this option to ground and hide the negative terminals. Clear this parameter to expose the negative terminals. By exposing these terminals, you can connect them to other parts of your model.

By default, this option is selected.

Modeling

Model frequency-dependent antenna parameters, specified as:

  • Time-domain (rationalfit) — This technique creates an analytical rational model that approximates the whole range of the data.

  • Frequency-domain — This technique computes the baseband impulse response for each carrier frequency independently. This technique is based on convolution. There is an option to specify the duration of the impulse response. For more information, see Compare Time and Frequency Domain Simulation Options for S-parameters.

The frequency-dependent parameters are:

  • Antenna impedance — The input impedance at the antenna terminals. This is used in RF system simulation.

  • Normalized vector effective length — A property used that ties between the current flowing at the antenna terminals and the radiated far-field at a given direction. Due to reciprocity, the effective length also ties between the incident field and the induced open-circuit voltage on the antenna terminals.

Dependencies

To set source Source of antenna model of Antenna Designer or Antenna object to activate the Modeling Tab that contains the Modeling options parameters.

Relative error acceptable for the rational fit, specified as a scalar. Applies to time-domain modeling of both antenna impedance and normalized vector effective length. The corresponding rational fitting results for each property are displayed on the block mask.

Dependencies

To set Modeling options to Time domain (rationalfit) in .

Select this parameter to automatically calculate the impulse response duration. Clear this parameter to manually specify the impulse response duration using Impulse response duration. Applies to frequency-domain modeling of both antenna impedance and normalized vector effective length.

Dependencies

To set this parameter, select Frequency domain in Modeling options.

Impulse response duration, specified as a scalar. Applies to frequency-domain modeling of both antenna impedance and normalized vector effective length.

Dependencies

To set this parameter, first select Frequency domain in Modeling options. Then, clear Automatically estimate impulse response duration.

More About

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References

[1] Stutzman, Warren L., and Gary A. Thiele. Antenna Theory and Design. 3rd ed. Hoboken, NJ: Wiley, 2013

[2] Farr, Everett G. “Characterizing Antennas in the Time and Frequency Domains [Education Corner].” IEEE Antennas and Propagation Magazine 60, no. 1 (February 2018): 106–10. https://doi.org/10.1109/MAP.2017.2774200.

See Also

| | (Communications Toolbox)

Introduced in R2020b