High-Pass Filter (HPF) is a fundamental filtering device for RF and analog circuits.
It only allows high-frequency signals above the preset cutoff frequency to pass through, while drastically attenuating and blocking low-frequency clutter, DC components and low-frequency interference below the cutoff point.
Often used together with low-pass or band-pass filters, it eliminates baseband low-frequency noise, power supply low-frequency ripples and harmonic spurs to purify RF transmit and receive signals.
Classified into passive LC HPFs and active op-amp HPFs, it is massively adopted in radar, satellite communication, broadband wireless transmission and signal test instruments. Core parameters: cutoff frequency, in-band insertion loss, stopband attenuation, port VSWR.