关键词: 西勒振荡电路, 同轴介质谐振器, 脉冲调制, 调制延时, 频率温度系数

Abstract: The working principle of λ/4 coaxial dielectric resonator is introduced. The resonator in the circuit is equivalent to a parallel resonant unit, which forms a capacitance three-point Siler oscillator circuit with coupling capacitance and feedback capacitance. The influence of coupling capacitance and feedback capacitance changes on the frequency temperature coefficient, start-up delay and output power is analyzed and studied. The appropriate capacitance value is optimally selected. A 1090 MHz pulse signal modulation oscillator circuit is designed. In the temperature range of -55-+85 ℃, the pulse modulation delay is equal?to or less?than?1 μs, the output power is (5±2) dBm, the output frequency is 1090 MHz±800 kHz, and the working current is less than 40 mA. The product is packaged in 20.4 mm×12.8 mm SMD, and the mass is less than 5 g. It has the characteristics of small volume, light weight, low power consumption, etc.

Key words: Siler oscillationcircuit, coaxial dielectric resonator, pulse modulation, modulation delay;frequency temperature coefficient