Portland Community College | Portland, Oregon

Course Number:
EET 223
Course Title:
RF Communications Circuits
Credit Hours:
Lecture Hours:
Lecture/Lab Hours:
Lab Hours:
Special Fee:

Course Description

Transistor and diode AC models and equivalent circuits. Design and analysis of multistage amplifiers and RF communications systems. Frequency response and Bode plots. A 3-hour per week laboratory includes measuring and analyzing the performance of transistor circuits in RF communications systems. Prerequisites: EET 221 Audit available.

Addendum to Course Description

The focus of this course is transistor amplifier characteristics and design. Amplifier input and output impedance, power dissipation and efficiency, and frequency response will be studied. These topics will be studied in the context of AM and FM communications systems. Frequency response analysis will include computer data acquisition methods and computer simulation methods, in addition to straight line Bode approximation.

Intended Outcomes for the course

1. Design and analyze multistage amplifiers and RF communications systems.

2. Analyze transistor and diode AC models and equivalent circuits.

3. Measure and analyze the performance of transistor circuits in RF communication systems

Outcome Assessment Strategies

Assessment methods are to be determined by the instructor. Typically, in class exams and quizzes, and homework assignments will be used. Lab work is typically assessed by a lab notebook, formal lab reports, performance of experiments, and possibly a lab exam.

Course Content (Themes, Concepts, Issues and Skills)

1.   FET circuit applications: amplifiers, current sources, switching, CMOS, power amplifiers, and oscillators. MOS-FET as a variable resistor. Capacitive loading of FET switching circuits.

2.   Brief treatment of h parameters and comparison to r parameters (device impedance and amplification expressed as h parameters).

3.   Series and shunt transistor circuit capacitances, including the "Miller Effect" capacitance.

4.   Current source models of transistors, and Thevenin equivalent circuits applied to frequency response calculation.

5.      Logarithms and decibels applied to amplifier system gain and frequency response.

6.      Transient response of transistor amplifiers. Amplitude and phase distortion.

7.      Multistage AC and DC amplifier circuits. Gain and frequency response of multistage amplifiers, including the "Darlington" and cascode types.

8.   Direct coupling, RC coupling, impedance coupling and transformer coupling of amplifier stages.   Applications include wide band
amplifiers, tuned amplifiers, and oscillators.

9.      Communication system principles: RF spectrum and signals, AM and FM modulation, noise sources and signal to noise ratio.

10.      Amplitude modulated transmitters: oscillators, RF amplifiers, modulators.

11.  AM Receivers: TRF, superheterodyne, RF and IF amplifiers, mixers, and demodulators.

12.      Frequency modulation transmitters: signal analysis and FM oscillators.

13.  FM receivers: limiters, demodulators.

14. Transmission lines and antennas: transmission line impedance and standing waves, electromagnetic waves, dipole, marconi, and directional antennas.