The invention relates to L-band RF (
Radio Frequency)
system output port protection equipment which comprises an L-band
RF system output port protection circuit arranged in a
metal sealed cavity, wherein the circuit comprises a coupler, a detection comparison circuit and a
digital control feedback circuit; the detection comparison circuit comprises a forward detection circuit, a reverse detection circuit, a tuning circuit and a
comparator; the data feedback circuit comprises a
data processing circuit, a VSWR (
Voltage Standing Wave Ratio) indication circuit and a protection judgment circuit; after the equipment is connected with an
RF system final
amplifier, an L-band
incident wave is separated from a reflected wave in proportion by utilizing the coupler, the separated reflection quantity and incidence quantity are compared by the detection comparison circuit, then a
logic level is output, and connected with the
digital control feedback circuit, and port matching is judged by
data processing, so that when a port is mismatched, the protection circuit can timely close a corresponding sending
signal, and a protection function is exerted; and the whole equipment has the characteristics that the equipment is small, exquisite, light, and sensitive in indication and judgment.