The invention discloses a 2-18GHz
square law detector, which comprises an input matching network, a
detector diode and a low-pass filter, and is characterized in that one end of the
detector diode isconnected with the input matching network, and the other end of the
detector diode is connected with the low-pass filter. The
Schottky diode is a P-type Schottky low-barrier detection diode SMS7630-079LF of Skyworks. The detector works in a
zero bias state; the working frequency range is 2-18 GHz, the
voltage sensitivity is higher than 1500 mV / mW through a rear-stage low-pass filter matched with afront-stage
impedance network, the
peak value of about 6000 mV / mW at 5 GHz is achieved, the corresponding NEP is superior to 1.49 pW / Hz, the bandwidth is wide, and the
harmonic suppression degree ishigh.