Tool comparisons, a matched-mesh FDTD benchmark, antenna how-tos, and how RayRF is checked against measured hardware. Written for working RF engineers.
RayRF's new PMC boundary and the mushroom EBG array from a classic IEEE EBG paper, cross-checked against openEMS on identical meshes. The EBG match dip agrees between the two solvers to 0.4 percent. Replication also uncovered and fixed a real via discretization bug. Full setup, mesh ladder, runtimes, and all project files.
I fabricated 4 RF PCBs on PTFE, measured 43 structures on a calibrated VNA, and simulated the same structures in RayRF. Resonances and poles track the measurements within 1-2% at the higher mesh refinements. Method, results, and what is next.
CST Studio Suite is a broad 3D EM suite leased at roughly 14,500 to 22,000 USD per year. For planar PCB RF, RayRF is a GPU FDTD tool at 1,499 USD per year with live results. What you keep and what you give up.
For planar PCB RF, RayRF is a GPU FDTD tool at 1,499 USD per year with a GUI and fast iteration, against published HFSS figures of 5,000 to 50,000 USD per year. What you gain and what you give up.
A like-for-like FDTD benchmark: an 82.8M-cell 5.8 GHz patch, 1,000,000 timesteps, one workstation. RayRF GPU ran 173.7x faster than openEMS (39,600 vs 228 MCell/s, 34m51s vs 4d5h). Numbers and method.
A practical walkthrough: estimate patch dimensions, build the stackup and feed, run a full-wave FDTD solve, read S11, and tune the match. Uses free calculators and RayRF.
openEMS is free and capable but needs scripting and runs on CPU. RayRF is a GUI FDTD simulator with a GPU solver that ran a head-to-head patch case 173.7x faster, validated against 43 VNA-measured structures.
FDTD, the finite-difference time-domain method, steps the electric and magnetic fields forward in time on a grid. A plain explanation of how it works, its trade-offs, and why GPUs suit it.