Tunable FiltersTunable filters are electronic components that are used to selectively pass or block certain frequencies of a signal. These filters are typically used in radio frequency (RF) and microwave applications, where they are used to filter out unwanted signals or to select a specific frequency band. Tunable filters are commonly made using metal-oxide-semiconductor field-effect transistors (MOSFETs), which are a type of transistor that is commonly used in RF and microwave circuits. Tunable filters can be adjusted or "tuned" to pass a specific range of frequencies, allowing them to be used in a variety of applications where the frequency response needs to be dynamically controlled.