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About Microwave and RF Circuit Design

Although RF circuits are generally considered to be circuits that operate from tens of MHz up to 1GHz, and microwave circuits at frequencies beyond that, boundaries based purely on frequency are rarely appropriate. Analog integrated circuits based on lower-frequency design methodologies can now operate well into the microwave range, purely because of smaller feature sizes that are now available in CMOS and silicon-germanium technologies. BiCMOS integrated circuits that operate in the microwave frequency range, designed using low frequency architectures, are now abundant. Rather than delineating design techniques based on frequency, we will focus on circuits that are differentiated from their historically lower-frequency counterparts by several features. In RF and MW design, the phase shift of the component is significant because its size is comparable with a wavelength, its reactances and parasitics must be accounted for, and reflections occur between elements. We need to consider circuit losses that degrade the Q of an element as well as introduce noise, and nonlinearities that introduce distortion into the signal path. Electromagnetic radiation and capacitive coupling will also be features of such circuits. With integrated circuits, these 'RF and microwave' effects are most commonly observed when assembling circuits together at higher frequencies into systems, or when using discrete or custom devices.

This course is a popular course that has been extensively updated to reflect modern trends. While still focusing on the design of discrete RF and microwave circuits to show classical microwave design techniques, examples of integrated circuits are presented to compare the 'two worlds'.

Impedance matching, device modeling, circuit stability, biasing, power output, distortion, power combining, and component losses and parasitics are examined, using state-of-the-art low-voltage transistors. This is illustrated in a number of applications such as small-signal, large-signal, low-noise, and feedback amplifiers. Low-noise design considerations are also introduced, using CAD modeling of reactive, resistive, and transformer types of applications. Reflecting its importance as a fundamental building block of most systems, amplifier design is treated exhaustively.

Oscillators and mixers are also designed to meet demanding systems requirements. We stress the importance of modeling parasitic elements that arise in design or when interconnecting components at high frequencies.

Nonlinear design techniques are examined using a harmonic balance simiulator , using bipolar, FET, and HEMT devices. Active device models are evaluated for various amplifier applications, considering linearity, efficiency, and power requirements. Many examples are related to cellular telephone circuits in the 950 MHz to 3 GHz frequency range. "Real-life" circuits are discussed, considering parasitics, losses and circuit layout effects. Interactive circuit simulation techniques are used throughout to simulate such effects on circuit performance.

Please bring your own scientific calculator and laptop computer.

Brief Course Outline

Active RF Circuit Design To introduce linear active circuits, we first examine fundamental limitations posed by noise and distortion. We start with the fundamental principles of impedance matching and move on to examine the effect of mismatch on performance.

• Linear and nonlinear concepts
• Review of the Smith Chart
• Impedance Matching
• Classical RF Circuit Stability: Graphical and analytical techniques
• Device Stabilization: Lossy and lossless feedback
• Simultaneous Conjugate Match, Bandwidth Considerations
• Multi-stage Amplifier Design Techniques

• Design for Optimal Power
• Quasi-Linear Methods to Achieve Power Matching: Load Line Characterization, Load Pull
• Characterization - Measurement and Prediction
• Classes of Power Amplifiers: A, AB, B, C, and F
• Harmonic Tuning to Optimize Efficiency
• Distortion Reduction Techniques
• Harmonic Balance Bipolar Amplifier Design Example (CDMA)

• Oscillator Design Considerations
• Device - Circuit Interaction (Series and Shunt Resonances)
• Phase Noise
• Microwave Bipolar Transistor (HBT) VCO Design: Example 4 GHz

• Revision of Diode Mixers
• Bipolar and MESFET Mixer Analysis
• Comparison of Mixer Types
• Modulators and Image-Reject Mixers

About the Presenter

Dr. Rowan Gilmore is an electrical engineer with thirty years experience working around the world in a variety of design and management positions in several industries. He gained his design experience over a number of years at Schlumberger (Houston), where he developed an RF tool for measurement of oil wells, and at Central Microwave (St. Louis), where he designed and developed numerous linear microwave power amplifiers, as well as oscillators and switching components. Subsequently, while at Compact Software (New Jersey), he was responsible for the development of their software suite of computer aided design tools. He was later Vice President at SITA-Equant (Sydney, Atlanta, London, Geneva), operator of the world’s most extensive data network, where he worked with a number of airlines and multinationals on their data telecommunications and IT needs. For the past four years, as the Chief Executive Officer of the Australian Institute for Commercialisation, located in Brisbane, Australia, he has worked on establishing liaisons and facilitating technology transfer between universities and industry. He also holds appointments as Adjunct Professor of Electrical Engineering, and in the School of Business, at the University of Queensland.

Dr. Gilmore is a Chartered Engineer and Senior Member of the IEEE. He has published more than thirty articles in the field of microwave systems and circuit design, and has served on the editorial boards of the IEEE Transactions on Microwave Theory and Techniques, and of Wiley's International Journal of RF and Microwave Computer-Aided Engineering. He has been active in the education of graduate engineers in industry, having taught courses around the world to nearly fifteen hundred practicing RF and microwave engineers for the over a decade. With Dr. Les Besser, he is co-author of the widely read two-volume textbook ‘Practical RF Circuit Design for Modern Wireless Systems’.

Rowan Gilmore received his undergraduate education at the University of Queensland, Brisbane, Australia, where he was awarded the University Medal and the B.E. degree in Electrical Engineering (Hons) in 1976, and his graduate education at Washington University in St. Louis where he was awarded the D. Sc. Degree in 1984. His research area was in the modeling of nonlinear behaviour in microwave MESFET circuits, as a result of which he was a pioneer in applying harmonic balance analysis to RF and microwave circuit design. Subsequently, while Vice President of Engineering with Compact Software, Dr. Gilmore led the introduction of Microwave Harmonica, the world's first commercial simulator applicable to the nonlinear design of microwave and RF circuits.

How to Register

Cancellation Policy

At least four weeks notice is required for cancellation of a place in a short course for full reimbursement. If cancellation is later than 4 weeks then the place can either be given to another person or the registrant can be provided with a credit towards other NICTA training.