Resistor

Model resistor for circuit envelope analysis

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Libraries:
RF Blockset / Circuit Envelope / Elements

Description

The Resistor block models a resistor within the RF Blockset™ circuit envelope simulation environment. For an introduction to RF simulation, see the example, Simulate High Frequency Components.

The block implements the relation

$$v(t)=Ri(t)$$

where:

• R represents the resistance, as a function of temperature.

• i(t) represents the current through the capacitor at time t.

• v(t) represents the voltage across the terminals of the capacitor at time t.

RF Blockset current and voltage signals consist of in-phase (I_k) and quadrature (Q_k) components at each frequency f_k specified in the Configuration block:

$$\begin{array}{c}i(t)={\displaystyle \sum _{\left\{f_k\right\}}\left(i_{I_k}(t)+j\cdot i_{Q_k}(t)\right)e^{j(2\pi f_k)t}}\\ v(t)={\displaystyle \sum _{\left\{f_k\right\}}\left(v_{I_k}(t)+j\cdot v_{Q_k}(t)\right)e^{j(2\pi f_k)t}}\end{array}$$

Resistor block mask icons are dynamic and indicate the current state of the applied noise parameter. This table shows you how the icons on this block vary based on the state of the Simulate noise parameter on the block.

Simulate noise: on	Simulate noise: off

To learn how you can use the Resistor block to design output matching network, open RF Receiver Front End subsystem and select Linear → Output Matching in Radar System Modeling example.

Examples

Analysis of Frequency Response of RF System

Analyze the frequency response of an RF system.

• Open Script

Radar System Modeling

Set up a radar system simulation consisting of a transmitter, a channel with a target, and a receiver.

• Open Script

Parameters

Resistance — Resistance value

50 Ohm (default) | real number in ohms

Resistance value , specified as a real number in ohms greater than zero. Specify the units of the resistance from the corresponding drop-down menu.

Simulate noise — Simulate thermal noise

on (default) | off

Select this parameter, to simulate thermal noise in a resistor. Then, in the Configuration block dialog box, also select the Simulate noise check box. By default, both Simulate noise check boxes are selected.

This parameter inserts a current noise source with the single-sided power density of 4 kT/R A²/Hz, where:

• k is the Boltzmann constant

• T is the value of the Temperature parameter, in degrees Kelvin. (Also located in the Configuration block.)

Version History

R2021b: Resistor block icon updated

Starting in R2021b, the Resistor block icon is now updated. The block icons are now dynamic and show the current state of the noise parameter.

When you open a model created before R2021b containing a Resistor block, the software replaces the block icon with the R2021b version.