High and Low A high-pass filter (HPF) attenuates content below a cut-off frequency, allowing higher frequencies to pass through the filter. A low-pass filter (LPF) attenuates content above a cut-off frequency, allowing lower frequencies to pass through the filter.
https://www.chelton.com/our-capabilities/antennas/rf-components/high-and-low-pass-filters/
https://www.chelton.com/our-capabilities/antennas/rf-components/high-and-low-pass-filters/