Sinusoid - Model modulated sinusoids in RF systems

Library

Sources

Description

The Sinusoid block models one or more modulated sine waves within the SimRF circuit-envelope simulation environment. For more information on simulating RF systems, see the example, Reduce Computations by Using RF Simulation Techniques.

The block implements the relation

or

to model either the voltage or current, as specified by the Source type, across the block at time t. The block defines the in-phase and quadrature components of the sinusoid, u_k(t) = u_k,i(t) + ju_k,q(t), according to the relations

where:

• D_i and D_q are DC offsets.

• A_i and A_q are amplitudes.

• ζ is a damping factor.

• τ is a time delay.

• m_k is the specified modulation frequency at a given carrier frequency f_k.

Dialog Box and Parameters

Source type

Specify the wave type as:

• Ideal Voltage — The block simulates a voltage envelope v(t) at the specified Carrier frequencies.

• Ideal Current — The block simulates a current envelope i(t) at the specified Carrier frequencies.

The default value of this parameter is Ideal Voltage.

Offset in-phase

Specify the in-phase offset, D_i, as a scalar or vector. Specify the units of the offset from the corresponding drop-down list. The default value of this parameter is 0 V for a voltage signal or 0 A for a current signal.

Offset quadrature

Specify the quadrature offset, D_q, as a scalar or vector. Specify the units of the offset from the corresponding drop-down list. The default value of this parameter is 0 V for a voltage signal or 0 A for a current signal.

Sinusoidal amplitude in-phase

Specify the in-phase amplitude, A_i, as a scalar or vector. Specify the units of the offset from the corresponding drop-down list. The default value of this parameter is 0 V for a voltage signal or 0 A for a current signal.

Sinusoidal amplitude quadrature

Specify the quadrature amplitude, A_q, as a scalar or vector. Specify the units of the offset from the corresponding drop-down list. The default value of this parameter is 0 V for a voltage signal or 0 A for a current signal.

Sinusoidal modulation frequency

At each carrier f_k specified by the Carrier frequencies parameter, specify the modulation frequency m_k. Specify the units from the corresponding drop-down list. The default value of this parameter is 0 Hz.

Time delay

Specify the time delay, τ, of the modulation as a scalar or vector. Specify the units from the corresponding drop-down list. The default value of this parameter is 0 s.

Damping factor (1/s)

Specify the damping factor, ζ, of the modulation as a nonzero scalar or vector with nonzero elements. The default value of this parameter is 0 s^-1, representing an undamped sinusoid.

Carrier frequencies

Enter a vector of carrier frequencies whose elements are a subset of the frequencies specified in the SimRF Parameters block. Specify the units from the corresponding drop-down list. The default value of this parameter is 0 Hz.

Ground and hide negative terminals

Select this check box to internally ground and hide the negative terminals of the block. Clear the check box to expose the negative terminals, allowing you to connect them to other parts of your model. By default, this check box is selected.

Examples

In the Demos section, the demo Validating IP2/IP3 Using Complex Signals highlights the difference between sinusoidal SimRF and Simulink sources and shows how to use them in the same model.

The section Model an RF Mixer uses a Sinusoid block to model an AM waveform at the input port of a mixer.

See Also

Continuous Wave

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