By Kevin Harrison
Filters are a staple of RF designers everywhere, and especially in applications where the integrity of the signal cannot be compromised. When you’re only concerned about a single frequency, it’s relatively easy to add in a fixed-tuned filter. However, it becomes slightly more difficult when you need to cover multiple frequencies and can’t just utilize a roofing filter. To avoid having to use a bunch of individual filters, basically creating a complex switched filter bank module, a tunable filter may be the solution.