A Design Of 24~28GHz VCO For The Ultra Wideband Millimeter Wave Frequency Source

With the rapid development of wireless communication technology,the scarcity of low frequency band,the millimeter wave technology for wireless communications become a research hotspot at home and abroad because of its rich spectrum resources and high transmission rate.In wireless communication system,the frequency source are the core component that provides high accuracy and high stability signals,and its performance directly affects the whole system.In high frequency band,PLL is the mostly used circuit to implementation frequency sources.As the core components of PLL,VCO's performance directly affects the quality of output signals in PLL.This thesis,based on the 0.13?m SiGe BiCMOS technology,implementation a design of 24~28GHz VCO for ultra-wideband millimeter-wave source.This thesis compares the performance of ring oscillators,Colpitts oscillators and cross-coupled oscillators and chooses common-collector differential Colpitts architecture to design VCO.The circuit of differential Colpitts VCO is optimized,especially the resonant circuit in VCO.In the resonant circuit of VCO,the added blocking capacitors are used for making the most of tuning voltage.New capacitors are added to the resonant in VCO,which achieves wider tuning range and lower phase noise at the same time.With 3.3V power supply,TT corner,tuning voltage form 0 to 3.3V and temperatures of-55,27,85 and 125?,this thesis runs an EM/Circuit Co-Simulation for the designed VCO.Simulation results show that at 27? the VCO covers frequencies from 23.95 to 30.00 GHz with the phase noise from-82.70 to-85.49dBc/Hz@100kHz and from-102.92 to-105.84dBc/Hz@1MHz respectively.The core working current is between 13 and 13.85 mA.In this thesis,the designed VCO can meet the requirements of the ultra-wideband millimeter-wave frequency source,which has great reference value for the design of Ka-Band VCO in the future.