Quite Universal Circuit Simulator (QUCS) is a great little Spice-like open-source tool that runs quickly, has a wide range of components, rather intuitie interface (but a so-so manual), and will execute S-parameter analysis. Available at qucs.sourceforge.net/.
What are the engineering and design challenges in creating successful IoT devices? These devices are usually small, resource-constrained electronics designed to sense, collect, send, and/or interpret data. Some of the devices need to be smart enough to act upon data in real time, 24/7. Specifically the guests will discuss sensors, security, and lessons from IoT deployments.