Description

4-Week RF Circuit Design Workshop

Week 1 — RF Fundamentals and ADS Basics

Day 1 — Saturday: RF Circuit Fundamentals

• Introduction to RF and microwave circuits
• Frequency, wavelength, phase, and impedance
• Resistance, reactance, and complex impedance
• R, L, and C components at RF frequencies
• Series and parallel RLC circuits
• Resonance and quality factor
• Introduction to S-parameters
• $S_{11}$, $S_{21}$, $S_{12}$, and $S_{22}$
• Return loss, insertion loss, isolation, and VSWR
• Smith chart fundamentals
• Basic impedance-matching concepts

Day 2 — Sunday: Keysight ADS Fundamentals

• ADS interface
• Creating projects and workspaces
• Schematic creation
• Component libraries
• Setting frequency sweeps
• S-parameter simulations
• AC simulations
• Introduction to harmonic balance
• Parameter sweeps
• Equation blocks
• Data display
• Smith chart plotting
• Tuning tool
• Optimization controller
• Basic RF circuit simulation examples

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Week 2 — Matching Networks and Antenna Equivalent Circuits

Day 3 — Saturday: RF Matching Circuit Design

• Introduction to impedance matching
• 50-$Omega$ RF systems
• Source and load impedance
• Smith-chart-based impedance matching
• Series and shunt matching elements
• L-section matching networks
• RLC-based matching networks
• Single-band antenna matching circuit
• Selection of R, L, and C values
• Matching-network simulation in ADS
• Parameter tuning
• Matching-network optimization
• Comparing antenna response before and after matching

Day 4 — Sunday: Antenna Equivalent Circuit Modeling

• Introduction to antenna equivalent circuits
• Physical meaning of R, L, and C in antenna models
• Single-resonance RLC modeling
• Single-band antenna equivalent circuit
• Extracting approximate R, L, and C values
• Dual-band antenna equivalent circuit
• Two-resonator circuit models
• Tri-band antenna equivalent circuit
• Three-resonator circuit models
• Series and parallel resonator combinations
• Resonance-frequency tuning
• Bandwidth control using RLC parameters
• Fitting ADS circuit response with CST $S_{11}$
• Equivalent-circuit optimization in ADS

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Week 3 — MIMO, PIN Diodes, Varactors, and Reconfigurable Antennas

Day 5 — Saturday: MIMO Equivalent Circuits and Active RF Components

• Introduction to two-port networks
• Two-port MIMO antenna equivalent circuit
• Multi-port S-parameter concepts
• Mutual coupling between antenna ports
• Circuit representation of coupling
• Isolation in equivalent circuit models
• Coupled RLC resonators
• PIN diode fundamentals
• PIN diode ON-state equivalent circuit
• PIN diode OFF-state equivalent circuit
• Series resistance, inductance, and junction capacitance
• Basic PIN diode biasing concepts
• Varactor diode fundamentals
• Varactor equivalent circuit
• Voltage-dependent capacitance
• Using varactors for continuous frequency tuning

Day 6 — Sunday: Reconfigurable Antenna Simulation

• Adding PIN diode equivalent models in CST
• Adding varactor models in CST
• Modeling ON/OFF switching states
• Frequency-reconfigurable antenna simulation
• Frequency switching using PIN diodes
• Frequency tuning using varactors
• Pattern-reconfigurable antenna simulation
• Current-path switching
• Parasitic-element switching
• Ground/radiator switching concepts
• Introduction to polarization reconfiguration
• Simulation of multiple antenna states
• Comparison of S-parameters for different switching conditions
• Optimization of diode locations and lumped-element values

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Week 4 — Phase Shifters, Power Dividers, and EM/Circuit Co-Simulation

Day 7 — Saturday: Phase Shifters and Power Dividers

• Introduction to RF phase shifting
• Phase response of RF circuits
• PIN diode phase shifters
• Switched-line phase shifters
• Varactor-based phase shifters
• Continuous phase tuning
• $45^circ$, $90^circ$, and $180^circ$ phase-shift concepts
• Phase-shifter simulation in ADS
• Phase-shifter optimization
• Introduction to RF power dividers
• Two-way power divider
• Equal power division
• Wilkinson power divider
• Isolation resistor
• Input and output matching
• Power-divider S-parameter analysis
• Wilkinson power-divider simulation and optimization in ADS

Day 8 — Sunday: EM/Circuit Co-Simulation and Final Simulation Project

• Exporting S-parameters from CST
• Introduction to Touchstone files
• $S1P$, $S2P$, and multi-port files
• Importing CST antenna results into ADS
• Combining EM antenna models with RF circuits
• Adding matching networks to simulated antennas
• Adding lumped RLC components to antenna models
• Adding PIN diode circuits to simulated antenna results
• Adding varactor-based tuning circuits
• EM/circuit co-simulation
• Parameter tuning and optimization
• Comparison between CST and ADS responses
• Resonance-frequency comparison
• Bandwidth comparison
• Isolation comparison for MIMO antennas
• Optimization of complete antenna-circuit systems

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Final Hands-On Simulation Project

Participants can complete one simulated design such as:

• Single-band antenna matching network
• Single-band RLC equivalent circuit
• Dual-band antenna equivalent circuit
• Tri-band antenna equivalent circuit
• Two-port MIMO equivalent circuit
• PIN-diode frequency-reconfigurable antenna
• Varactor-tuned antenna
• Pattern-reconfigurable antenna
• PIN-diode phase shifter
• Varactor-based phase shifter
• Wilkinson power divider
• CST-to-ADS antenna circuit co-simulation