A reader shared some thoughts the other day on a multicomponent design that was meant for a wireless application. Part of the frequency coverage was within the traditional 18-GHz range of many microwave systems, while some multiplication might have been required to take this design into the millimeter-wave region for some of the design's functionality. As we discussed the design, both of us somewhat "long in the tooth" in terms of our RF experience, design software wasn't initially mentioned in the discussion, but it inevitably became part of it.

It occurred to me that at one time, this discussion took place without software, and the design was done "on paper," by sketching out function blocks and the appropriate signal-processing functions and equations on a piece of paper in order to work out a proof of concept for the design. Now, there are few designers who would think of starting a design this old way, without the use of a favorite computer-aided-engineering (CAE) software tool or suite of tools, such as the popular Advanced Design System (ADS) from Agilent Technologies or Microwave Office from AWR. Modern software design tools contain arrays of proven function blocks and device models, and can greatly accelerate the time from concept to prototype. While we older folks may bemoan the loss of the "paper method," most of us have to agree that the software approach saves time and, for the most part, aggravation.