Microwave engineering is a field of study that aims to understand and utilize electromagnetic waves in the microwave frequency range from a few hundred megahertz to a few hundred gigahertz. The development of microwave engineering has led to significant breakthroughs in various industries, including telecommunications, radar technology, and electronic devices, among others. In his book, "Foundations Microwave Engineering," Collin, Robert E., highlights the timeless principles and concepts that form the cornerstone of this field of study. This article delves into the key ideas outlined in the book and their relevance in current and emerging microwave technologies.

Chapter 1: Introduction

The first chapter of "Foundations Microwave Engineering" provides an introduction to the field of microwave engineering. It defines microwaves as electromagnetic waves that have a wavelength between 1 mm and 1 m and operate in the frequency range of 300 MHz to 300 GHz. The chapter highlights the importance of microwaves in modern communication systems, such as satellite communication, cellular telephony, and wireless local-area networks (WLANs). The chapter also touches on the historical development of microwave engineering, tracing its roots back to the early 20th century.

Chapter 2: Transmission Lines

Chapter two covers the basics of transmission lines, including the different types of materials used to construct them and their applications. The chapter also addresses characteristic impedance, power transfer, and reflection coefficients. The concept of standing wave ratio and its uses in measuring the efficiency of a transmission line is also discussed. The chapter concludes by examining several transmission line examples, including coaxial cables, microstrip lines, and waveguides.

Chapter 3: Waveguides

Chapter three delves deeper into waveguides. The chapter starts by defining waveguides as hollow metallic tubes that transmit electromagnetic waves from one point to another. It highlights the various types of waveguides, including rectangular, circular, and elliptical waveguides. The chapter tackles the concept of cutoff frequency, dispersion, and waveguide modes. Other topics covered in this chapter include losses in waveguides and waveguide components.

Chapter 4: Microwave Network Analysis

Chapter four discusses the concept of network analysis in microwave engineering. The chapter starts by examining S-parameters, which are used to evaluate the performance of microwave networks. It defines S-parameters as a measure of the reflection and transmission of a microwave network or device. The chapter outlines several techniques used in microwave network analysis, including T-parameters, Y-parameters, and Z-parameters. The chapter concludes by exploring the design of microwave amplifiers using scattering parameters.

Chapter 5: Impedance Matching

Chapter five focuses on the concept of impedance matching in microwave circuits. The chapter explains the importance of impedance matching in achieving maximum power transfer between the source and the load. The chapter starts by defining impedance and reflection coefficients. It then highlights the different types of impedance matching techniques, including quarter-wave transformers, lumped element matching, and stub matching. The chapter concludes by examining the role of network analyzer in impedance matching.

Chapter 6: Microwave Resonators

Chapter six delves into the concept of microwave resonators, which are essential components in microwave circuits. The chapter defines resonators as a closed cavity that can confine electromagnetic radiation to resonate at specific frequencies. The chapter covers several types of microwave resonators, including cavity resonators, coaxial resonators, and microstrip resonators. The chapter concludes by exploring the applications of microwave resonators in filters, oscillators, and amplifiers.

Chapter 7: Power Dividers and Directional Couplers

Chapter seven examines the concept of power dividers and directional couplers in microwave engineering. The chapter defines power dividers as passive components used to split and combine microwave signals. It also explores different types of power dividers, including resistive divider, hybrid divider, and Wilkinson divider. The chapter then focuses on the concept of directional couplers, which are used to couple microwave energy from one circuit to another. The chapter concludes by examining the design of power dividers and directional couplers.

Chapter 8: Microwave Filters

Chapter eight delves into microwave filters, essential components in microwave engineering. The chapter defines filters as circuits used to remove unwanted frequencies from a signal. The chapter examines several types of filter designs, including low-pass, high-pass, band-pass, and band-stop filters. The chapter covers various filter topologies, such as Butterworth, Chebyshev, and Bessel filters. The chapter concludes by exploring the design of microwave filters using distributed elements.

Chapter 9: Active Microwave Circuits

Chapter nine focuses on active microwave circuits, which include components such as amplifiers, oscillators, and mixers. The chapter examines the need for active components in microwave circuits and highlights the benefits of using them. The chapter covers different types of amplifiers, such as the common-source amplifier and the cascode amplifier. It also discusses the concept of oscillator design and outlines various types of oscillators. The chapter concludes by examining mixer circuits, a critical component in frequency conversion circuits.

Chapter 10: Microwave Measurements

Chapter ten explores the concept of microwave measurements, which are crucial in the design and characterization of microwave components and systems. The chapter starts by examining the concept of calibration, which is essential in ensuring the accuracy of microwave measurements. The chapter covers the different types of calibration, such as the TRL calibration and the SOLT calibration. The chapter also explores different measurement techniques, including time-domain reflectometry, network analysis, and vector network analysis.


In conclusion, "Foundations Microwave Engineering" by Collin, Robert E., highlights the fundamental principles and concepts of microwave engineering. The book covers a wide range of topics, including transmission lines, waveguides, impedance matching, microwave resonators, and microwave measurements. These concepts are essential in the design and analysis of various microwave systems, including communication systems, radar technology, and electronic devices. Understanding these principles is critical in keeping up with the emerging trends and technologies in the field of microwave engineering.