sparameters

Calculate S-parameter for antenna and antenna array objects

Syntax

sobj = sparameters(antenna,freq)

sobj = sparameters(antenna,freq,Z0)

sobj = sparameters(array,freq)

sobj = sparameters(array,freq,Z0)

sobj = sparameters(filename)

sobj = sparameters(data,freq)

sobj = sparameters(data,freq,Z0)

sobj = sparameters(netparamobj)

sobj = sparameters(netparamobj,Z0)

Description

sobj = sparameters(antenna,freq) calculates the complex s-parameters for an antenna object over specified frequency values.

sobj = sparameters(antenna,freq,Z0) calculates the complex s-parameters for an antenna object over specified frequency values and for a given reference impedance, Z0.

sobj = sparameters(array,freq) calculates the complex s-parameters for an array object over specified frequency values .

sobj = sparameters(array,freq,Z0) calculates the complex s-parameters for an array object over specified frequency values and for a given reference impedance, Z0.

sobj = sparameters(filename) creates an S-parameter object sobj by importing data from the Touchstone file specified by filename.

sobj = sparameters(data,freq) creates an S-parameter object from the S-parameter data, data, and frequencies, freq.

sobj = sparameters(data,freq,Z0) creates an S-parameter object from the S-parameter data, data, and frequencies, freq, with a given reference impedance Z0.

sobj = sparameters(netparamobj) converts the network parameter object, netparamobj, to S-parameter object with the default reference impedance.

sobj = sparameters(netparamobj,Z0) converts the network parameter object, netparamobj, to S-parameter object with a given reference impedance, Z0.

Examples

Calculate S-Parameter Matrix For Antenna

Calculate the complex s-parameters for a default dipole at 70MHz frequency.

 h = dipole

h = 
  dipole with properties:

        Length: 2
         Width: 0.1000
    FeedOffset: 0
     Conductor: [1x1 metal]
          Tilt: 0
      TiltAxis: [1 0 0]
          Load: [1x1 lumpedElement]

 sparameters (h, 70e6)

ans = 
  sparameters: S-parameters object

       NumPorts: 1
    Frequencies: 70000000
     Parameters: 0.1887 - 0.0045i
      Impedance: 50

  rfparam(obj,i,j) returns S-parameter Sij

Calculate S-parameter Matrix For Array

Calculate the complex s-parameters for a default rectangular array at 70MHz frequency.

h = rectangularArray;
sparameters(h,70e6)

ans = 
  sparameters: S-parameters object

       NumPorts: 4
    Frequencies: 70000000
     Parameters: [4x4 double]
      Impedance: 50

  rfparam(obj,i,j) returns S-parameter Sij

Extract and Plot S-Parameters data from Touchstone File

Extract S-parameters from corrugatedconicalhorn.s2p touchstone file .

sobj = sparameters('corrugatedconicalhorn.s2p');
display(sobj)

sobj = 
  sparameters: S-parameters object

       NumPorts: 1
    Frequencies: [11x1 double]
     Parameters: [1x1x11 double]
      Impedance: 50

  rfparam(obj,i,j) returns S-parameter Sij

Plot the S-parameters data using rfplot function.

rfplot(sobj)

Input Arguments

antenna — Antenna object

scalar handle

Antenna object, specified as a scalar handle.

array — Array object

scalar handle

Array object, specified as a scalar handle.

freq — S-parameter frequencies

vector of positive real numbers

S-parameter frequencies, specified as a vector of positive real numbers, sorted from smallest to largest.

Z0 — Reference impedance

50 (default) | positive real scalar

Reference impedance in ohms, specified as a positive real scalar. You cannot specify Z0 if you are importing data from a file. The argument Z0 is optional and is stored in the Impedance property.

data — S-parameter data

array of complex numbers

S-parameter data, specified as an array of complex numbers, of size N-by-N-by-K where K represents number of frequency points.

netparamobj — Network parameter object

network parameter object

Network parameter object. The network parameter objects are of the type: sparameters (RF Toolbox), yparameters (RF Toolbox), zparameters (RF Toolbox), gparameters (RF Toolbox), hparameters (RF Toolbox), abcdparameters (RF Toolbox), and tparameters (RF Toolbox).

Example: S1 = sparameters(Y1,100) . Y1 is a parameter object. This example converts Y-parameters to S-parameters at 100 ohms.

filename — Touchstone data file

character vector | string scalar

Touchstone data file, specified as a character vector, that contains network parameter data. filename can be the name of a file on the MATLAB^® path or the full path to a file.

Example: sobj = sparameters('defaultbandpass.s2p');

Output Arguments

sobj — S-parameter data

S-parameter object

S-parameter data, returned as an object. disp(sobj) returns the properties of the object:

• NumPorts — Number of ports, specified as an integer. The function calculates this value automatically when you create the object.

• Frequencies — S-parameter frequencies, specified as a K-by-1 vector of positive real numbers sorted from smallest to largest. The function sets this property from the filename or freq input arguments.

• Parameters — S-parameter data, specified as an N-by-N-by-K array of complex numbers. The function sets this property from the filename or data input arguments.

• Impedance — Reference impedance in ohms, specified as a positive real scalar. The function sets this property from the filename or Z0 input arguments. If no reference impedance is provided, the function uses a default value of 50.

Version History

Introduced in R2015a