RF Design Blogs

The Team RF "μWaveRiders" blog series debuts as a showcase for Cadence AWR RF products. Monthly topics will vary between Cadence AWR Design Environment release highlights, feature videos, Cadence Academic Network news (now includes the former AWR University Program), as well as software tips, tricks, customization, and feature spotlights. To receive notifications about new blogs in this series, click Subscribe Now and submit your email ID in the Subscriptions box.

The AWR University Program began in 2002 with seven students at seven universities on three continents. Prior to joining the Cadence Academic Network in 2020, the AWR flexible licensing program grew to about 4000 students at nearly 300 universities every semester, aside from the estimated 1000 students at schools using network licenses, for which there is no measurable usage data.

For students in the RF/microwave area of study, the Cadence AWR Design Environment platform provides a range of tools that are extremely useful for many tasks, ranging from theoretical concept verification to advanced design capabilities covering the entire industry. The AWR academic license bundle includes capabilities such as:

• A schematic and physical layout that share a universal database, where changes in either window affect the circuit in both windows
• Linear circuit analysis (frequency domain)
  • passive circuits (filters, power dividers, couplers, etc.)
  • small signal amplifiers (LNAs, highly linear amplifiers)
• Nonlinear circuit analysis
  • Harmonic Balance (frequency domain)
  • Transient (time domain)
• The Cadence AWR AXIEM 3D planar electromagnetic (EM) solver using Method of Moments
• The Cadence AWR Analyst 3D FEM EM solver using Finite Element Method
• The Cadence AWR Visual System Simulator (VSS) communications and radar systems design software, offering several system-level analysis capabilities:
  • RF Budget: cascaded behavioral elements (AMP, FILTER, MIXER, etc.)
  • RF Inspector: highly-detailed analysis of all spectral elements generated in a circuit. Amplifiers generate harmonics up to a user-specified level. Mixers generate intermodulation frequencies up to a user-specified level. All these terms interact and are tracked through a system.
  • Time Domain: analysis for digitally modulated signals, ranging from basic schemes such as QAM (Quadrature Amplitude Modulation) to the newest 5G modulation schemes.
• Wizards: several synthesis tools for filters, matching networks, general network synthesis, Frequency Planning, and others.

The various tools are integrated into a single design environment, allowing interaction between them. Two examples of this interoperability follow (see upcoming blogs for details of each):

MOVING CIRCUIT DESIGNS UP TO THE SYSTEMS LEVEL

A user can start to design an RF system using the behavioral models in AWR VSS software to generate what is known as an “ideal” system. Once these elements are defined at the behavioral level, each subcircuit can be designed in the Cadence AWR Microwave Office software, and the real designs can replace the behavioral models that were used to create the system. These images shows a bandpass filter where a behavioral model has been replaced with a user-defined LC filter:

Ideal System

Ideal System with Filter Design

DRIVING EM ANALYSIS WITH SCHEMATIC LAYOUT

A desired layout may have complicated features that are not well handled by the ideal schematic elements. (The simplest example would be transmission lines that are using basic single-line models, but that are close enough that there is some coupling between the lines.) A feature called “EM extraction” allows a schematic layout to drive an EM solver, which will calculate an exact solution for the physical structure. The schematic elements generate the physical layout that is used to drive the EM simulation, and these schematic elements are effectively removed from the schematic. The solution for the removed schematic elements is replaced by the EM solution, and then all other elements are reconnected to the EM solution at the proper ports, to create the total solution. The remove/reconnect process is 100% automated.

Schematic Layout with SMT Components

Extracted EM Structure

The AWR University Program includes a technical support resource that is available to both students and faculty. It also allows professors to request a live tutorial during a scheduled class session that will focus on the portions of the AWR Design Environment platform that are related to the topics of study for that class. An introductory RF/microwave class typically benefits from a tutorial that covers a passive structure such as a filter or power divider, while a more advanced class might be focused on power amplifiers or target antennas. These tutorials cover the full range of applications and are generally available upon request.

For questions about the AWR University Program, send an email to awr.university.program@cadence.com.

By: Mark Saffian
Consultant - WFO
Cadence AWR R&D - U.S.

Related Resources

Blogs

• Expanding Our Network — AWR Academic Partners
• Cadence Academic Network Welcomes AWR and EMX Users to Join Us!

• University Program
• Cadence Academic Network

Contact Us

For questions, general feedback, or suggestions for future blog topics, write to team_rf_blogs@cadence.com. 

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