The W-band High-frequency Stability Voltage Controlled Oscillator

Voltage controlled oscillator (VCO) is a key component of modern electronic equipments. The main purpose of this thesis is to improve the 3mm VCOs frequency stability that work in harmonic to obtain the more strict demands of new electronic equipments. The equivalent circuits is synthesized for the case where the TE10 mode is the only propagating waveguide mode, which based on basic waveguide-circuits equivalent circuits such as cross-coupled coaxial line rectangular waveguide junctions, rectangular waveguide transmission lines etc. Then we make the computation program for the equivalent circuits to analyse and optimize the VCO circuit, and get the each parameter's influences on VCO output signal. Due to this, we insert a metal slice in the sub cavity as a reactance compensator. The experiment results show it really works.Four oscillators is tested in two groups, two oscillators' center frequency can be debugged from 93GHz to 94.5GHz with output power over 10mW, and voltage controlled bandwidth can reach 900MHz(controlled voltage 0V～9.3V) and linearity of VCO is better than 1.33% with voltage controlled bandwidth 400MHz. During operating temperature range -40~+55℃, The frequency stability of the one group work in 94.5GHz are -0.46 MHz/℃ & -0.43MHz/℃ and the other group work in 93GHz are -0.46 MHz/℃ & +0.4MHz/℃.