rfckt.parallel

Parallel connected network

Description

Use the parallel class to represent networks of linear RF objects connected in parallel that are characterized by the components that make up the network. The following figure shows a pair of networks in a parallel configuration.

Creation

Syntax

h = rfckt.parallel

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

Description

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

h = rfckt.parallel('Ckts',value) returns a cascaded 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

1-by-N character array

Object name, specified as an 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. nportt 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 X-Y 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

Network of RF Objects In Parallel

Create a network of transmission lines connected in parallel using rfckt.parallel.

tx1 = rfckt.txline;
tx2 = rfckt.txline;
rfplel = rfckt.parallel('Ckts',{tx1,tx2})

rfplel = 
   rfckt.parallel with properties:

              Ckts: {[1x1 rfckt.txline]  [1x1 rfckt.txline]}
             nPort: 2
    AnalyzedResult: []
              Name: 'Parallel 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 admittance matrix of the parallel connected network. It starts by converting each component network's parameters to an admittance matrix. The following figure shows a parallel connected network consisting of two 2-port networks, each represented by its admittance matrix.

   

   where

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

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

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

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

References

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

Version History

Introduced before R2006a