Issue link: https://iconnect007.uberflip.com/i/1496727
14 DESIGN007 MAGAZINE I APRIL 2023 ey are. But a lot of them are etched out of the board trace. ey're soldered on as a compo- nent, so an RF engineer has already done the design work. You connect a proper coplanar waveguide trace to a pin of a three-pin surface mount device. Holden: The phase of a radar is multiple antennas, because they're on different layers of the board and they actually direct the electromagnetic field. Exactly. ey direct the field in different direc- tions. Matties: What does the typical PCB designer need to know about designing RF boards? I'd start with comparing the additive process vs. the subtractive process, and what that means for the design. Part of that is the skin effect, and RF that needs to be taken into account and why additive rather than subtractive processes are necessary. For proper performance discus- sions, it's important to understand the com- plexities of dealing with multiple different RF frequencies running simultaneously, as well as interference and interaction. At companies where I've worked, we've usu- ally had a dedicated person to do this compli- ance verification and validation for FCC or EU, or whatever your region. How do you deal with FCC compliance when you've got four or five different frequencies running simultaneously, and that actually need to be EMI emissive? How do you deal with emissivity and suscep- tibility when you are the generating source and need to be the receiver of those energies but also not interfere with the surrounding devices? It's complex. Shaughnessy: What's the criteria involved in deciding to design an antenna vs. using a COTS antenna? Historically, you did it yourself with copper geometry because there simply were no COTS RF parts. Antennas were not commercially available a few years ago. e other reason is board area real estate. e COTS antenna may be too big and I have a very limited real estate that I need to fit this into, so I need to custom design my antenna to fit in this little corner of my board because that's the only area of my product that I can safely remove all shielding material so it can act as an antenna and not shield my RF signals from getting in or out. Shaughnessy: Who are the new, young RF designers of today? Are they being mentored by the outgoing members of the "old guard?" A lot of the old RF guys aren't in the field any- more. Honestly, you would find a lot of the new RF guys are making the smartphones. e military contractors in the U.S. would also have upcoming RF design engineers. A lot of the newest RF stuff is happening in IoT and smartphones. Matties: If I'm looking to hire an RF designer, who am I looking for? An electrical engineer? Yes, it's going to be someone with an EE degree with a specialty in RF, but very few engineers get straight RF degrees anymore. You need You need that specialized RF training, or at least access to an RF engineering specialist, to go through the three-dimensional geometry calculations for some of this design work.