rfckt.series

Series connected network

Description

Use the rfckt.series object to create networks of linear RF objects connected in series that are characterized by the components that make up the network. The following figure shows a pair of networks in a series configuration.

Note

circuit object and add function is recommended over rfckt.hybrid because the add function enables you to insert linear and nonlinear elements into a circuit object to create networks of any topology which includes a hybrid, an inverse hybrid, a parallel, and a series connected network. (since R2023b)

Creation

Syntax

h = rfckt.series

h = rfckt.series('Ckts',value)

Description

h = rfckt.series returns a series connected network object whose properties all have their default values.

h = rfckt.series('Ckts',value) returns a series connected network with elements specified in the name-value pair property Ckts.

Properties

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

rfdata.data object

Computed S-parameters, noise figure, OIP3, and group delay values, specified as rfdata.data object. Analyzed Result is a read-only property. For more information, see Algorithms.

Data Types: function_handle

Ckts — Circuit objects in network

cell array of object handles

Circuit objects in network, specified as a cell array of object handles. All circuits must be 2-port. By default, this property is empty.

Data Types: char

Name — Object name

'RLCG Transmission Line' (default) | 1-by-N character array

Object name, specified as a 1-by-N character array. Name is a read-only property.

Data Types: char

nport — Number of ports

positive integer

Number of ports, specified as a positive integer. nport is a read-only property. 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

Series Connected RF Network Object

Create a series connected RF network object using rfckt.series

tx1 = rfckt.txline;
tx2 = rfckt.txline;
ser = rfckt.series('Ckts',{tx1,tx2})

ser = 
   rfckt.series with properties:

              Ckts: {[1x1 rfckt.txline]  [1x1 rfckt.txline]}
             nPort: 2
    AnalyzedResult: []
              Name: 'Series Connected Network'

Algorithms

The analyze method computes the S-parameters of the AnalyzedResult property using the data stored in the Ckts property as follows:

1. The analyze method first calculates the impedance matrix of the series connected network. It starts by converting each component network's parameters to an impedance matrix. The following figure shows a series connected network consisting of two 2-port networks, each represented by its impedance matrix.

   

   where

   $$\begin{array}{l}\left[Z^{\prime }\right]=\left[\begin{array}{cc}{Z}_{11}{}^{\prime }& Z_{12}{}^{\prime }\\ Z_{21}{}^{\prime }& Z_{22}{}^{\prime }\end{array}\right]\\ \left[Z^{″}\right]=\left[\begin{array}{cc}{Z}_{11}{}^{\prime \text{}\prime }& Z_{12}{}^{\prime \text{}\prime }\\ Z_{21}{}^{\prime \text{}\prime }& Z_{22}{}^{\prime \text{}\prime }\end{array}\right]\end{array}$$

2. The analyze method then calculates the impedance matrix for the series network by calculating the sum of the individual impedances. The following equation illustrates the calculations for two 2-port circuits.

   $$\left[Z\right]=\left[Z^{\prime }\right]+\left[Z^{″}\right]=\left[\begin{array}{cc}{Z}_{11}{}^{\prime }+Z_{11}{}^{\prime \text{}\prime }& Z_{12}{}^{\prime }+Z_{12}{}^{\prime \text{}\prime }\\ Z_{21}{}^{\prime }+Z_{21}{}^{\prime \text{}\prime }& Z_{22}{}^{\prime }+Z_{22}{}^{\prime \text{}\prime }\end{array}\right]$$

3. Finally, analyze converts the impedance matrix of the series network to S-parameters at the frequencies specified in the analyze input argument freq.

References

[1] Ludwig, Reinhold and Pavel Bretchko, RF Circuit Design: Theory and Applications, Prentice-Hall, 2000.

Version History

Introduced in R2009a