Systems which remove unwanted frequencies including digital filters, nonlinear filters and superconducting filters


  • Channel bank filters - a filter that demultiplexes a group of communication channels, such as those in along a analog or digital telephone line
  • Digital filters - electronic filters that perform mathematical operations on discrete-time signals to reduce or enhance aspects of those signals
  • Equalizers - equipment that reduces distortion in audio frequencies by increasing or decreasing signal strength
  • Gabor filters - named after Dennis Gabor, linear filters used in image processing for edge detection
  • Kalman filters - an algorithm that provides an optimized estimate of a system's state (i.e. its position and velocity)
  • Matched filters - originally known as a North filter, a filter which applies a known signal or template to an unknown signal to detect the presence of the template in the unknown signal
  • Resonator filters - the use of a resonator, such as a helical resonator, in filtering