Electromagnetic waves (microwaves, millimeter waves, light waves) are used for applications such as signal transmission and sensing. These applications require controlling the propagation of electromagnetic waves depending on the purpose. Controlling the mode of electromagnetic waves that propagate through waveguides can realize the branching and coupling capabilities of electromagnetic power, as well as capabilities of frequency discrimination.
The instructor in this course will explain how the field distribution and propagation velocity of electromagnetic waves are determined when propagating in representative waveguides such as a coaxial line, metallic waveguide and dielectric waveguide. The instructor will also explain the scattering matrix used for characterizing guided wave circuits, then explain the operating principle and basic design methods of typical guided wave circuits for branching and coupling capabilities, frequency discrimination capability, and nonreciprocal functions that realize direction-dependent transmission of electromagnetic waves. Furthermore, the instructor will explain the concepts of the Radio Law.
By the end of this course, students should be able to:
1) Understand the characteristics of electromagnetic waves propagating in waveguides.
2) Represent the characteristics of electromagnetic wave circuits.
3) Explain and design the operation principles of representative electromagnetic wave circuits.
microwave, millimeter-wave, lightwave, coaxial line, metallic waveguides, dielectric waveguide, voltage and current distributions along a transmission line, impedance, standing wave, cut-off, scattering matrix, impedance matching, resonator, multi-/demultiplexer, nonreciprocal device, the Radio Law
|✔ Specialist skills||Intercultural skills||Communication skills||Critical thinking skills||✔ Practical and/or problem-solving skills|
A quiz will be given at the beginning of the class on the main points of that day's class, so students should read about the course content in advance to prepare.
|Course schedule||Required learning|
|Class 1||Fundamentals of electromagnetic analysis - complex representation of time varying electromagnetic field, Maxwell's equation||Understand the relation between complex and instantaneous representations of time varying electromagnetic field and Maxwell's equation.|
|Class 2||Transmission line equation and coaxial line - voltage and current distribution along a transmission line, input impedance and standing wave||Derive the distribution of voltage and current along a transmission line. Understand the relation between the impedance measured along the transmission line and the position measuring the impedance.|
|Class 3||Metallic waveguide - TE mode and TM mode, electromagnetic field in a waveguide, and cut-off||Derive the electromagnetic field distribution in a metallic waveguide.|
|Class 4||Dielectric waveguide - slab waveguide, guided mode and single mode condition||Understand the boundary condition imposed on the electromagnetic field propagating in a dielectric slab waveguide and derive the equation that determines the propagation constant.|
|Class 5||Matching circuit - quarter wavelength matching, stub||Understand the matching circuit.|
|Class 6||Branching and coupling circuits - magic-T and directional coupler||Represent the characteristics of branching and coupling circuit using a scattering matrix.|
|Class 7||Frequency discriminating circuits - resonator and multi-/demultiplexer||Understand the condition that determines the frequency characteristics of frequency selective circuits.|
|Class 8||Nonreciprocal circuit, the Radio Law and related act - isolator, circulator and the point of the Radio Law||Explain the difference between nonreciprocal and reciprocal circuits.|
Naito, Yoshiyuki. Microwave and Millimeter Wave Engineering. Tokyo: Corona; ISBN-978-4-339-00037-5. (Japanese)
You can download course materials at OCW/OCW-i.
I will evaluate your understanding of how the electromagnetic field distribution and propagation constant of guided modes are determined in waveguides, concepts of impedance and standing wave, and operation and design principles of waveguide circuits. Midterm and final exams 80%, Exercise Problems 20%.
Students are requested to have passed Electricity and Magnetism I and II.
e-mail for appointment.