ECE 453

• Electromagnetics, Optics and Remote Sensing

The purpose of this course is to teach senior students in electrical engineering the basic principles of radio-frequency circuit design and to illustrate how such circuits are used in communication systems.

• Receiver systems: modulation schemes; receiver fundamentals; superheterodyne receiver
• Resonant circuits and impedance transformations
• Oscillators: hybrid Pi model for BJT and FET; loop gain analysis; negative resistance analysis
• Impedance matching: L networks, PI and T networks (lossless and attenuating); Smith chart
• High frequency amplifier design: 2 port models - Y, Z, H, S parameters; stability, power gains, simultaneous conjugate matching
• Noise characterization of systems: introduction to thermal noise characteristics; noise characterization of linear 2 ports; sensitivity of receiving system; measurement techniques
• Nonlinear effects: 1 dB compression; two-tone response of nonlinear system, third-order intercepts; dynamic range of receiving system
• Mixers: active mixers; switching type mixers; 4-diode double balanced mixer; conversion loss, nonlinear effects
• Phase-locked loops and applications: FM detection; frequency synthesis

The purpose of this course is to teach senior students in electrical engineering the basic principles of radio-frequency circuit design and to illustrate how such circuits are used in communication systems.

Topics:

• Receiver systems: modulation schemes; receiver fundamentals; superheterodyne receiver
• Resonant circuits and impedance transformations
• Oscillators: hybrid Pi model for BJT and FET; loop gain analysis; negative resistance analysis
• Impedance matching: L networks, PI and T networks (lossless and attenuating); Smith chart
• High frequency amplifier design: 2 port models - Y, Z, H, S parameters; stability, power gains, simultaneous conjugate matching
• Noise characterization of systems: introduction to thermal noise characteristics; noise characterization of linear 2 ports; sensitivity of receiving system; measurement techniques
• Nonlinear effects: 1 dB compression; two-tone response of nonlinear system, third-order intercepts; dynamic range of receiving system
• Mixers: active mixers; switching type mixers; 4-diode double balanced mixer; conversion loss, nonlinear effects
• Phase-locked loops and applications: FM detection; frequency synthesis

CAD Software (HP Microwave and RF design systems) is used in the laboratory.

Design, construct, match, and test a crystal oscillator and a radio-frequency amplifier operating at approximately 50 MHz; noise measurements; laboratory notebook required; instrumentation: vector impedance meter, spectrum analyzer, network analyzer, synthesizers.

vector impedance meter, spectrum analyzer, network analyzer, frequency synthesizers.

• Network theory
• Fourier series
• Electronic circuits
• Smith chart

Class notes.

Engineering Science: 2 credits or 50%
Engineering Design: 2 credits or 50%

The goals are to introduce students to circuits and systems employed for radio communication, and to provide an introduction to methods for analysis, design, and experimental measurement and characterization of communication circuits and systems. This course includes a laboratory section.

A. By the time of Exam No. 1 (after 19 lectures), the students should be able to do the following:

1. Identify and write mathematical expressions for carrier signals modulated using amplitude or angle modulation. (1)

2. Determine or estimate the bandwidth of a modulated carrier signal. (1)

3. Understand and analyze the operation of a superheterodyne receiver employing single or multiple frequency conversions. (1)

4. Design a superheterodyne receiver at the block-diagram level, including specification of required filter characteristics. (1,2)

5. Analyze an LC or quartz crystal oscillator circuit to determine conditions required for oscillation to start and to determine the frequency of oscillation. (1)

6. Design an LC or quartz crystal oscillator for operation at a specific frequency. (1,2)

7. Design a matching network using 2 lossless elements to match complex source and load impedances. (1,2)

8. Design a matching network using 3 lossless elements to match real source and load impedances with specified bandwidth. (1,2)

9. Design a matching network consisting of cascaded L-sections to match real source and load impedances with specified bandwidth. (1,2)

10. Measure the complex impedance of components at high frequencies using a Vector Network Analyzer. (1,3,4,5,6,7)

11. Derive high frequency circuit models for passive components. (1,3,6,7)

12. Use a Vector Signal Analyzer to characterize a radio frequency signal. (1,3,5,6,7)

B. By the time of Exam No. 2 (after 36 lectures), the students should be able to do all of the items listed under A, plus the following:

13. Understand Z, Y, h, ABCD and scattering parameter descriptions of a linear 2-port. (1)

14. Derive the 2-port Z, Y, h, ABCD, or S-parameter matrix for a given network. (1)

15. Derive the 2-port parameter matrix for series, parallel, and cascade combinations of sub-networks. (1)

16. Measure the scattering parameters of a linear 2-port using a Vector Network Analyzer. (1,3,5,6,7)

17. Use scattering parameters of a 2-port to predict the input and output impedance, and power transfer between arbitrary complex source and load impedances. (1,7)

18. Determine if a 2-port is unconditionally stable, or not. If not, predict what source and load impedances can lead to instability. (1,7)

19. Design a small signal linear amplifier with conjugately matched input and output ports using scattering parameters. (1,6,7)

20. Understand the properties of a lossless filter network in terms of the scattering parameters. (1)

21. Understand the Butterworth, Chebyshev, Bessel low-pass filter approximations. (1)

22. Design a lossless low-pass filter using an LC ladder network and the Butterworth, Chebyshev, or Bessel approximation. (1,6,7)

23. Design a bandpass filter by transforming a low-pass prototype filter. (1,2,7)

24. Understand how to parameterize 2-port noise in terms of an effective input temperature. (1)

25. Apply Friis' formula to predict the effective input temperature of a cascade of noisy 2-ports. (1,7)

26. Calculate the effective input temperature of a passive, linear, lossy 2-port. (1,7)

27. Calculate the signal to noise ratio at the demodulator input given the effective noise temperature of the antenna and the 2-ports that comprise the receiver. (1,7)

28. Understand the Y-factor method for measuring the effective input temperature of a 2-port, including the influence of measurement inaccuracies. (1)

29. Measure the Noise Figure of a 2-port using an automated Noise Figure Meter. (1,3,5,6,7)

C. By the time of the Final Examination (after 41 lectures), the students should be able to do all of the items listed under A and B, plus the following:

30. Understand the origin of intermodulation products in a nonlinear 2-port. (1)

31. Predict the frequencies of intermodulation products at the output of a nonlinear 2-port resulting from multiple input tones. (1,7)

32. Measure the 1 dB compression level and the two-tone third-order intercept level for a nonlinear 2-port. (1,3,5,6,7)

33. Understand the definition of Spurious-Free Dynamic Range (SFDR) and determine SFDR for a receiving system. (1)

34. Understand and analyze the operation of a passive switching mixer implemented using 3-winding transformers and diodes. (1)

35. Understand and analyze the operation of active mixers implemented using BJT and MOS transistor switches. (1)