Wave trap circuit for suppressing local oscillator leakage of frequency mixer

• Main Authors: MO KUNSHAN, LI HAIBING, QIN XU, LI YONGTAO, WANG PENGJU, GE XIAONA
• Format: Patent
• Language: Chinese; English
• Published: 27.08.2021
• Subjects: BASIC ELECTRONIC CIRCUITRY; ELECTRIC COMMUNICATION TECHNIQUE; ELECTRICITY; IMPEDANCE NETWORKS, e.g. RESONANT CIRCUITS; RESONATORS; TRANSMISSION

The invention belongs to the field of radio-frequency signal processing circuits, and particularly relates to a wave trap circuit for suppressing local oscillation leakage of a frequency mixer, which comprises a radio-frequency input transformer and a radio-frequency output transformer, and is characterized by further comprising a plurality of resonant circuits and LC network circuits; the number of the resonant circuits and the LC network circuits is n; the resonant circuits comprise a plurality of quartz crystals which are connected in parallel, and the frequency of the quartz crystals is consistent with the local frequency; the LC network circuits are a 1/4 wavelength impedance conversion circuits; the LC network circuits and the resonant circuits are connected in series at intervals; the output end of the radio-frequency input transformer is electrically connected with the input end of the first resonant circuit, and the electric input end of the radio-frequency output transformer is electrically connecte