Phase-frequency characteristic detector and phase-frequency characteristic detection method

The invention relates to a phase-frequency characteristic detector and a phase-frequency characteristic detection method. The phase-frequency characteristic detector comprises a dual-phase adjustable signal generator and a modulation method based phase detection unit, wherein one output port of the dual-phase adjustable signal generator is connected with one input port of the modulation method based phase detection unit, and the other output port of the dual-phase adjustable signal generator is connected with another input port of the modulation method based phase detection unit through a detected network. The phase-frequency characteristic detector further comprises an analog-digital conversion circuit, wherein the analog-digital conversion circuit is connected with the phase output voltage end of the modulation method based phase detection unit, the output end of the analog-digital conversion circuit is connected with the input end of the dual-phase adjustable signal generator through a digital control unit, and the digital control unit is connected with a displaying unit and a setting unit. The phase-frequency characteristic detector provided by the invention is easy and convenient to operate, has high detection precision, can evade the area with big detection error of the modulation method based phase detection unit, can directly judge that the detected network is a lead network or lag network and can obtain the phase displacement of the detected network.