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Analyze circuit object in frequency domain

`analyze(h,freq)`

analyze(h,freq,zl,zs,zo,aperture)

analyze(h,freq,'* condition1*',

`value1`

`conditionm`

`valuem`

`analyze(h,freq)`

calculates
the following circuit data at the specified frequency values:

Circuit network parameters

Noise figure

Output third-order intercept point

Power data

Phase noise

Voltage standing-wave ratio

Power gain

Group delay

Reflection coefficients

Stability data

Transfer function

`h`

is the handle of the circuit object to
be analyzed. `freq`

is a vector of frequencies, specified
in hertz, at which to analyze the circuit. OIP_{3} is
always infinite for passive circuits.

`analyze(h,freq,zl,zs,zo,aperture)`

calculates
the circuit data at the specified frequency values. The arguments `zl`

, `zs`

, `zo`

,
and `aperture`

are optional. `zl`

, `zs`

,
and `zo`

represent the circuit load, circuit source,
and reference impedances of the S-parameters, respectively. The default
value of all these arguments is 50 ohms.

When you specify impedance values, the `analyze`

method
changes the object's values to match your specification.

The `aperture`

argument determines the two
frequency points that the `analyze`

method uses
to compute the group delay for each frequency in `freq`

. `aperture`

can
be a positive scalar or a vector of the same length of as `freq`

.

For `rfckt.datafile`

, `rfckt.passive`

, `rfckt.amplifier`

,
and `rfckt.mixer`

objects that contain measured S-parameter
data, the `analyze`

method uses the two nearest
measurement points to compute the group delay, regardless of the value
of `aperture`

.

Group delay *τ _{g}* at
each frequency point

$${\tau}_{g}(f)=-\frac{\Delta \varphi}{\Delta \omega}=-\frac{\mathrm{arg}\left({S}_{21}({f}_{+})\right)-\mathrm{arg}\left({S}_{21}({f}_{-})\right)}{2\pi \left({f}_{+}-{f}_{-}\right)}$$

*f*_{+}is:*f*(1 +`aperture`

/2) for`aperture`

< 1.*f*+`aperture`

/2 for`aperture`

≥ 1.

If

*f*is the maximum value of`freq`

, then*f*_{+}=*f*.*f*_{–}is:*f*(1 –`aperture`

/2) for`aperture`

< 1.*f*–`aperture`

/2 for`aperture`

≥ 1.

If

*f*is the minimum value of`freq`

, then*f*=_{–}*f*.

By default, `analyze`

calculates the
group delay in nanoseconds.

The value of `aperture`

affects the accuracy
of the computed group delay. If `aperture`

is too
large, the slope estimate may be not accurate. If `aperture`

is
too small, the computer numerical error may affect the accuracy of
the group delay result.

`analyze(h,freq,'`

calculates
the circuit data at the specified frequency values and operating conditions
for the object * condition1*',

`value1`

`conditionm`

`valuem`

`h`

. The inputs `'``condition1`

',`value1`

,...,'`conditionm`

',`valuem`

are
the condition/value pairs at which to analyze the object. Use this
syntax for `rfckt.amplifier`

, `rfckt.mixer`

,
and `rfdata.data`

objects where the condition/value
pairs are operating conditions from a `.p2d`

or `.s2d`

file.When you specify condition/value pairs, the `analyze`

method
changes the object's values to match your specification.

When you analyze a network that contains several objects, RF Toolbox™ software
does not issue an error or warning if the specified conditions cannot
be applied to all objects. For some networks, because there is no
error or warning, you can call the `analyze`

method
once to apply the same set of operating conditions to any objects
where operating conditions are applicable. However, you may want to
analyze a network that contains one or more of the following:

Several objects with different sets of operating conditions.

Several objects with the same set of operating conditions that are configured differently.

To analyze such a network, you should use the `setop`

method to configure the operating conditions
of each individual object before analyzing the network.

For most circuit objects, the `AnalyzedResult`

property
is empty until the `analyze`

method is applied to
the circuit object. However, the following four circuit objects are
the exception to this rule:

`rfckt.datafile`

— By default, the`AnalyzedResult`

property of`rfckt.datafile`

objects contains the S-parameter, noise figure, and group delay values that are calculated over the network parameter frequencies in the`passive.s2p`

data file. OIP3 is ∞ by default because the data in`passive.s2p`

is passive.`rfckt.passive`

— By default, the`AnalyzedResult`

property of`rfckt.passive`

objects contains the S-parameter, noise figure, and group delay values that are the result of analyzing the values stored in the`passive.s2p`

file at the frequencies stored in this file. These frequency values are also stored in the`NetworkData`

property. OIP3 is always ∞ for`rfckt.passive`

objects because the data is passive.`rfckt.amplifier`

— By default, the`AnalyzedResult`

property of`rfckt.amplifier`

objects contains the S-parameter, noise figure, OIP3, and group delay values that result from analyzing the values stored in the`default.amp`

file at the frequencies stored in this file. These frequency values are also stored in the`NetworkData`

property.`rfckt.mixer`

— By default, the`AnalyzedResult`

property of`rfckt.mixer`

objects contains the S-parameter, noise figure, OIP3, and group delay values that result from analyzing the values stored in the`default.s2p`

file at the frequencies stored in this file. These frequency values are also stored in the`NetworkData`

property.

For a detailed explanation of how the `analyze`

method
calculates the network parameters, noise figure values, and OIP3
values for a particular object, see the `AnalyzedResult`

property
on the reference page for that object.

`calculate`

| `extract`

| `getz0`

| `listformat`

| `listparam`

| `loglog`

| `plot`

| `plotyy`

| `polar`

| `read`

| `restore`

| `semilogx`

| `semilogy`

| `smith`

| `write`

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