Frequency discriminating circuit

Abstract

Abstract PURPOSE:To make the oscillation frequency stable at all times, by performing phase detection for the signal through a coupling circuit between a resonator and a line, with the signal through the coupling circuit between the resonator and the line and picking up the phase difference of both the signals as the frequency discriminating output. CONSTITUTION:To the coupling section between lines 12, 14 and a dielectric resonator 13 for microstrip lines 12 and 14, end opposite to an oscillator FET1 is short-circuited with lines 15a, 15b. Further, a the extension of the lines 12, 14 is made wider to form a 90 deg. hybrid coupler 15. Further, the end of extension of the lines 12, 14 of the coupler is grounded via diodes 16, 17 of opposite polarity. That is, a phase detector 20 is constituted with the coupler 15 and the diodes 16, 17, and a signal through the coupling circuit with the resonator 13 and the line 12 is phase-detected with the signal through the coupling circuit between the resonator 13 and the line 14, and the phase difference between both the signals is picked up as a frequency discriminating output VD. Thus, the oscillated frequency can always be stabilized.

Inventors

• 👤 Takashi Otobe
• 👤 Yasutoshi Komatsu
• 👤 Yoshikazu Murakami

Bibliographic Details