Laboratorio RF

Experiment 1: Introduction to the Spectrum Analyzer
Purpose and Discussion
The purpose of this simulation is to demonstrate the characteristics and operation of the Spectrum Analyzer as it appliesto radio frequency (RF) communications. The Spectrum Analyzer is one of the most essential testing instruments in the field of communications. To this point, the oscilloscope has been relied upon toanalyze AC signals and their relationships to one another. The oscilloscope allows measurements of phase variations between signals as well as period, amplitude and overall signal performance. The timeversus amplitude scale, however, does not allow the specific components of a signal to be studied. The Spectrum Analyzer measures signals in the frequency domain, decomposing them into spectral linesat different frequencies. Ideally, a perfect undistorted sine wave is connected to the input of a Spectrum Analyzer. A single vertical line at its fundamental frequency of oscillation is observed.However, signal sources in the real world are not perfect. They always create some distortion which results in tiny spectral lines. These lines are multiples of the fundamental frequency and are low inamplitude. Spectral analysis is encouraged in Multisim through use of the Spectrum Analyzer. Multiple duplicate instruments may be utilized for further convenience in the study and testing of ACsignals.

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Understanding RF Circuits with Multisim

Parts
AC Voltage Source

Test Equipment
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Oscilloscope Spectrum Analyzer

Formulae
Power in watts P = Vrms 2/ RL
Equation 1-1Procedure

Figure 1-2

1. Connect the circuit illustrated in Figure 1-2. 2. Double-click on the AC Voltage Source. Select the Value tab and set Voltage (Pk) = 10V, Voltage Offset = 0V andFrequency = 1 kHz. Click OK. 3. Double-click on the Oscilloscope. Set the time division to 1 ms/Div and the Amplitude to 5 V/Div. Start the simulation and observe the 1 kHz frequency on the time versus...