Excitation Signal

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Within this dialog box you can specify a transient excitation signal.

Note that the property units refer to the units set in the Transient Simulation Task dialog box.

Type frame

Within this frame, you may select the type of the excitation signal. A preview image of the selected signal is shown at the bottom of this frame.

Select type: Select the type of the excitation signal here. The following types are available:

Gauss: Select this option to specify a gaussian excitation signal that is defined by a frequency interval and a voltage amplitude.

Pulse: Select this option to specify a pulsed excitation signal. Have a close look at the preview for further information about its definition.

Sine: Select this option to specify a sinusoidal excitation signal that is defined by a voltage amplitude, a voltage offset, a frequency and a time delay.

Damped sine: Select this option to specify a damped sinusoidal excitation signal. In addition to the definitions for the sinusoidal signal a damp factor can be specified here.

Exponential: Select this option to specify an exponential excitation signal that is defined by an initial voltage value, a final (asymptotic) voltage value, a time delay and a time constant.

Exponential rising and falling: Select this option to specify an exponential excitation signal that is initially rising and after a given time falling or vice versa. The definitions are almost the same like for the exponential excitation signal, but two time delays and two time constants have to be specified here. Have a close look at the image. In particular, pay attention to the time delays.

The following options are bit sequences. The definition of the pulses' properties are identical for all of them. Note that a pulse constants either of a rising and a hold part or of a hold and a falling part or simply of a hold part. The duration of a pulse is constant. Therefore the hold time depends on whether there is a rising or a falling part and on whether identical values are specified for the rise and the fall time.

Double Exponential: Select this option to specify a double exponential excitation signal that is used for instant for lightning pulse approximations.

ASCII import: Select this option to specify a file to read the excitation signal from. This file should contain two columns for time and signal values. As a delimiter you may choose SPACE, TAB or any combination of them.

Impulse: Select this option to specify an impulse signal. A highest required output frequency (Fmax) should be specified to define the shape of this signal. The impulse function gives an excitation signal that provides a uniform amplitude in the frequency domain from 0Hz to Fmax.

 

The following options are bit sequences. The definition of the pulses' properties are identical for all of them. Note that a pulse constants either of a rising and a hold part or of a hold and a falling part or simply of a hold part. The duration of a pulse is constant. Therefore the hold time depends on whether there is a rising or a falling part and on whether identical values are specified for the rise and the fall time.

 

Pulse Sequence: This bit sequence signal allows a very general pulse definition and a bit sequence, given by a string composed of "ones" and "zeros".

PRBS: Select this option to specify a pseudo-random binary sequence. The number of pulses is given by 2N. The first N pulses are 1-Bits.

PRBS random initialization: Almost similar to the previous option, but the first N pulses are generated by random.

K 28.5: Select this option to specify a bit sequence according to the K 28.5 data pattern which consists of 20 Bits.

K 28.5 inverted: Select this option to obtain the inversion of the previous option

Random: Select this option to specify a random binary sequence. The number of pulses is given by N.

Select file for ASCII import type: Browse for an ASCII file here if 'ASCII import' is selected.

Preview: Shows a schematic figure of the selected excitation type.

Source frame

Set the type of source inside this frame. The settings frame will refer to the specified type then. Note that the units selected in the Transient Simulation Task dialog box are applied.

Voltage: Specify a voltage signal source.

Current: Specify a current signal source.

Signal: Specify a signal source according to the signal definition in CST MICROWAVE STUDIO® here. The unit of such a signal is √W.

Settings frame

The contents of this frame changes according to the selected type and the selected source (see above). Note that the units selected in the Transient Simulation Task dialog box are applied to the values specified here.

Fmin: Gaussian: Specify the lower frequency limit here.

Fmax: Gaussian: Specify the upper frequency limit here.

Use reference Fmin/Fmax: Gaussian: If selected, the frequency range is taken from the Reference frequency range setting of the Transient Simulation Task dialog box. It also influences the normalization of frequency domain results.

Freq: Sine/Damped sine: Specify the signal frequency here.

V/C/Sampl: Gauss/Sine/Damped sine: Specify the voltage/current/signal amplitude here.

V/C/Soffset: Sine/Damped sine: Specify the voltage/current/signal offset here.

V/C/Sinit: Pulse/Exponential/Exponential rising and falling: Specify the initial voltage/current/signal value here.

V/C/Send: Exponential: Specify the asymptotic voltage/current/signal end value here.

V/C/Spulse: Pulse/Pulse Sequence/PRBS/K 28.5/Random: Specify the pulse voltage/current/signal value here. Exponential rising and falling: Specify the asymptotic voltage/current/signal end value for the rising part here.

V/C/Shigh: Pulse Sequence: Specify the voltage/current/signal amplitude of a "logical high" bit here.

V/C/Slow: Pulse Sequence: Specify the voltage/current/signal amplitude of a "logical low" bit here.

Tdelay: Pulse: Specify the delay time here. During this period the signal holds the value specified for "Vinit". Sine/Damped sine/Exponential: Specify an initial time delay here.

Tdelayrise: Exponential rising and falling: Specify the delay time for the rising part here.

Pulse Sequence: Specify the delay from an imaginary trigger-event (defined by Ttotal/2.0 and a 0-1 transition in the bit sequence) to the beginning of the rising flank.

Tdelayfall: Exponential rising and falling: Specify the delay time for the falling part here.

Pulse Sequence: Specify the delay from an imaginary trigger-event (defined by Ttotal/2.0 and a 1-0 transition in the bit sequence) to the beginning of the falling flank.

Trise: Pulse/Pulse Sequence/PRBS/K 28.5/Random: Specify the rise time here.

Thold: Pulse/Pulse Sequence: Specify the hold time here. During this period the signal holds the value specified for "Vpulse".

Tfall: Pulse/Pulse Sequence/PRBS/K 28.5/Random: Specify the fall time here.

Ttotal: Pulse/Pulse Sequence: Specify the total duration of a 1-0 pulse transition.

Tpulse: PRBS/K 28.5/Random: Specify the pulse width of one pulse here.

Crise: Exponential/Exponential rising and falling: Specify the rising constant here.

Cfall: Exponential rising and falling: Specify the falling constant here.

Damp: Damped Sine: Specify a linear damping factor per time unit here.

InitBit: Pulse Sequence: Specify the bit state that should be assumed before the  actual bit sequence starts. The value needs to be either "1" (logical high) or "0" (logical low)

BitSequence: Pulse Sequence: Specify the pulse sequence by a string of "1" and "0".

N: PRBS: Specify the order of the bit sequence here. As a result you will obtain a sequence of 2N bits. Random: Specify the number of bits here.

OK

Stores the current settings and leaves the dialog box.

Cancel

Closes this dialog box without performing any further action.

Help

Shows this help text.

 

Note:

If more than one bit-like signal ("Pulse Sequence/PRBS/K 28.5/Random") is defined not all settings can be specified individually. Some settings ("N, Wrap, Prebits, Ttotal and Tpulse") are specified by the firstly defined bit signal and can only be changed there.

See also

Transient Simulation Task