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High-speed PCB design is complex enough, but RF design can be a whole new ball game. RF designers have to contend with tuning and other ideas that traditional PCB designers don’t have to worry about, as well as crosstalk, parasitic capacitance, and material limitations.
Most PCB design tool companies now offer RF design options, so designers no longer have to use pureplay RF design tools for anything but the most cutting-edge designs. Cadence Design Systems expanded its RF EDA offerings by acquiring the RF software company AWR a few years ago. We asked David Vye, product management director at Cadence, to share his thoughts on EDA software, RF design, and what new RF designers and engineers need to understand.
Andy Shaughnessy: David, what are the most common challenges facing PCB designers and EEs in the RF space today? So many electronic devices today have GPS, Bluetooth, and Wi-Fi all together on the same PCB, and you wonder how they can all “play nice” with each other.
David Vye: For some time, many of the challenges that come with implementing RF technology in PCB systems relate to trends that have been evolving with each new communication standard. These system requirements (think 4G, 5G, and now 6G) include greater integration of functionality, reduction in footprint and power consumption, the move to higher frequencies and/or bandwidths, as well as the adoption of beamforming antennas to extend the system range. For the RF engineer, this leads to multiple technical considerations such as maintaining signal integrity, managing multiple high-frequency signals, ensuring proper impedance matching, and minimizing noise and interference, all while balancing performance, manufacturability, and space constraints. You’ve mentioned several different wireless standards; many of them exist together in a single device, serving a wide range of applications and consumer preferences for speed, quality of service, battery life, and the lowest possible cost.
Fitting multiple radio front ends into the smallest possible form factor requires smart layout strategies, proper shielding to prevent high-frequency signals from coupling to sensitive traces, a solid understanding of performance vs. cost trade-offs pertaining to component selection, and an awareness of non-RF issues such as thermal and stress-related effects that can impact the reliability of a PCB-based system. These considerations can be addressed with design and simulation software that provides insight into optimal system architecture and component selection via budget analysis, PCB passive component design capabilities through RF circuit simulation, and design verification through electromagnetic and thermal analyses. To reduce design turnaround times, these capabilities offer the greatest benefit when they are tied into a layout platform that offers a constraint-driven PCB design approach, which emphasizes defining design intent through rules for electrical, physical, and manufacturing aspects, ensuring first-pass success and streamlining the design process.
To read this entire conversation, which appeared in the April 2025 issue of Design007 Magazine, click here.
