EEE 161
Applied Electromagnetics, Spring 2007.
Laboratory Exercise 6-Part II
Introduction to Transmission Lines– Phasors
Instead of ADS you can use the simulator of choice (Multisim, PSpice) that you have experience with!
Problem 1.Open a schematic diagram in ADS. From the pulldown menu select a Frequency-Domain Sinusoidal generator and connect it to a resistor. Double click on the generator and select the frequency of the source to be 1GHz. Select Transient Simulation and place it on the window. Place ampermeters and label branches. Simulate the circuit by pressing the gear icon. Open a data window by clicking on graph-paper icon. Save the data window data by selecting: File Save and give it THE SAME NAME as the schematic window. Select the x-y coordinates from the left side and place it on the window. A window opens. Select the named currents and voltages, and then select time-domain plot.lot voltage and current through this resistor when the frequency of the sinusoidal signal is 1GHz. Write magnitudes, time delays and phases of all currents and voltages in the circuit.
Problem 2. Using Transient Simulation, plot the currents and voltages in a series RL circuit. Measure the magnitude of the voltage on the resistor and inductor. Add them up. Do they add up to the voltage of the source? Why or why not?
Problem 3. Using Transient Simulation, plot the currents and voltages in a series RC circuit. Measure the magnitude of the voltage on the resistor and inductor. Add them up. Do the magnitudes of voltage add up to the voltage of the source?
Problem 4. Solve the problems 2 and 3 using phasors. Look at the KVL equation for the voltage. The voltage on the resistor and inductor (or capacitor) should add up to the voltage of the source. What is the issue in addition of these two voltages? Assuming you measured 1V for the voltage across the capacitor and 2V for the voltage across the resistor, is the source voltage then 3V? Why or why not. Draw a vector diagram for the voltage to prove your point.
Problem 5.Using Transient Simulation, plot the currents and voltages in a parallel RL circuit. Measure the magnitude of the current through the resistor and inductor. Add them up. Do they add up to the current of the source?
Problem 6. Using Transient Simulation, plot the currents and voltages in a parallel RC circuit. Measure the magnitude of the current through the resistor and inductor.
Problem 7. Solve the problems 5 and 6 using phasors. Look at KCL equation. The current through the resistor and inductor (or capacitor) should add up to source current. What is the issue in addition of these two currents? Draw a vector diagram for the voltage to prove your point.
Problem 8. Assume that a sinusoidal source is driving the linear circuit. Without knowing the topology of the circuit, what can you state about all currents and voltages in the circuit?