DTRI-EE0901: Microwave Tubes and Transmission Lines

Microwave engineering is not a subject that students like. But that does not mean it is a boring topic. In this course I have made a sincere attempt to make it interesting for you to understand the concepts rather than just memorize the content.

If you are a student, this course should help you get high grades in your tests.

If you are professional microwave/ RF engineer this course will help refresh your basics.

Please do not hesitate to provide your honest feedback by highlighting corrections, any additional topics you want me to cover or just anything. I will for sure take it in right spirit! Thank you.

This course covers following topics:

• Introduction to Microwave Tubes

• Reflex Klystron Oscillator

• Mechanism of Oscillations

• Qualitative Analysis of Mode Curves

• Microwave Devices and Systems

• Transmission line equations and Solutions

• Reflection Coefficient and Transmission Coefficient

• Standing Wave Ratio

• Smith Chart

• Single Stub Matching

Microwave tubes have a long history with applications predominantly in warfare. These high power, high frequency tubes are used both as signal generators and signal amplifiers.

This course focusses on a specific microwave device – the Reflex Klystron oscillator, used as signal generator. The course delves into design, mechanism of how oscillations are created and various oscillation modes based on frequency and power requirements.

What exactly is a microwave device? What is its definition in frequency range? These are the questions answered in this course.

A high-level understanding of various microwave devices and then putting them together to form a complete system which comprises of transmitter and receiver is covered in this course.

Many electrical, electronics and communication engineers have heard the phrase transmission line quite often. But what exactly is a transmission line? Is it a simple wire? Is USB cable a transmission line? What about the power cord connected to your laptop? These are some questions which will be answered in this course.

Two major specifications used to define microwave devices - reflection coefficient and standing wave ratio are explained in this course.

A popular and must know Microwave Tool – The Smith Chart is explained in detail.

Finally, an introduction to the term matching and a practical method of matching called single stub matching is explained in this course.