rfckt.datafile

Component or network from file data

Description

Use the datafile object to represent RF components and networks that are characterized by measured or simulated data in a file.

Use the read method to read the data from a file in one of the following formats:

• Touchstone

• Agilent^® P2D

• Agilent S2D

• AMP

Note

sparameters is recommend over rfdata.datafile because it enables you to calculate S-parameters for RF data, network, circuit, and matching network objects. (since R2023b)

Creation

Syntax

h = rfckt.datafile

h = rfckt.datafile(Name,Value)

Description

h = rfckt.datafile returns a circuit object whose properties all have their default values.

h = rfckt.datafile(Name,Value) sets properties using one or more name-value pairs. For example, rfckt.datafile('IntType','Cubic') creates an RF component or network that uses cubic interpolation. You can specify multiple name-value pairs. Enclose each property name in a quote. Properties not specified retain their default values.

Properties

AnalyzedResult — Computed S-parameters, noise figure, OIP3, and group delay values

rfdata.data object

This property is read-only.

Computed S-parameters, noise figure, OIP3, and group delay values, specified as a rfdata.data object. For more information refer, Algorithms.

Data Types: function_handle

File — File name containing circuit data

1-by-1 character array

File name containing circuit data, specified as a 1-by-1 character array.

Data Types: char

IntpType — Interpolation method

1-by-N character array

Interpolation method, specified as a 1-by-N character array of the following values:

Method	Description
Linear (default)	Linear interpolation
Spline	Cubic spline interpolation
Cubic	Piecewise cubic Hermite interpolation

Data Types: char

Name — Object name

1-by-N character array

This property is read-only.

Object name, specified as a 1-by-N character array.

Data Types: char

nport — Number of ports

positive integer

This property is read-only.

Number of ports, specified as a positive integer. The default value is 2.

Data Types: double

Object Functions

analyze	Analyze RFCKT object in frequency domain
calculate	Calculate specified parameters for rfckt objects or rfdata objects
circle	Draw circles on Smith Chart
extract	Extract specified network parameters from rfckt object or data object
listformat	List valid formats for specified circuit object parameter
listparam	List valid parameters for specified circuit object
loglog	Plot specified circuit object parameters using log-log scale
plot	Plot circuit object parameters on X-Y plane
plotyy	Plot parameters of RF circuit or RF data on xy-plane with two Y-axes
getop	Display operating conditions
polar	Plot specified object parameters on polar coordinates
semilogx	Plot RF circuit object parameters using log scale for x-axis
semilogy	Plot RF circuit object parameters using log scale for y-axis
smith	Plot circuit object parameters on Smith Chart
write	Write RF data from circuit or data object to file
getz0	Calculate characteristic impedance of RFCKT transmission line object
read	Read RF data from file to new or existing circuit or data object
restore	Restore data to original frequencies
getop	Display operating conditions
groupdelay	Group delay of S-parameter object or RF filter object or RF Toolbox circuit object

Examples

Represent RF Components and Networks In Data File.

Represent RF components and networks that are characterized by measured or simulated data in a file using rfckt.datafile.

data=rfckt.datafile('File','default.s2p')

data = 
   rfckt.datafile with properties:

          IntpType: 'Linear'
              File: 'default.s2p'
             nPort: 2
    AnalyzedResult: [1x1 rfdata.data]
              Name: 'Data File'

Algorithms

The analyze method computes the AnalyzedResult property using the data stored in the File object property. If the file you specify with this property contains network Y- or Z-parameters, analyze first converts these parameters, as they exist in the rfckt.datafile object, to S-parameters. Using the interpolation method you specify with the 'IntpType' property, analyze interpolates the S-parameters to determine the S-parameters at the specified frequencies. Specifically, analyze orders the S-parameters according to the ascending order of their frequencies, f_n. It then interpolates the S-parameters, using the MATLAB^® interp1 function. For example, the curve in the following diagram illustrates the result of interpolating the S₁₁ parameters at five different frequencies.

For more information, see “One-Dimensional Interpolation” and the interp1 reference page in the MATLAB documentation.

References

[1] EIA/IBIS Open Forum, Touchstone File Format Specification, Rev. 1.1, 2002

Version History

Introduced before R2006a