Ka-band Millimeter Wave Frequency Synthesizer Design

With the development of the modern wireless communications,the request for the frequency synthesizers is higher and higher in the system of the mobile communication,radar,guided weapon and electronic counter.The synthesizer with the low phase noise,highly pure spectrum and high stablity have became the tendency to the frequency synthesis technology.A high quality Ka-band frequency synthesizer is designed in this dissertation, which band is from 28.55GHz to 29.55GHz.The scheme is given after analyzing the targets of the system, and then the design steps are presented.The theory of PLL is first introduced by means of introducing the loop structure and designing the linear model.The concept of the phase noise is explained particularly as well as the phase noise model of the loop.After introducing the theory of PLL and oscillistor,the scheme using double loops is recommended according to the request of the system.One loop supplies microwave single signals,and the other supplies RF mixed signals.The final output is given after mixing the two loops and doubling.The microwave signals are got by the technology of DRO,which simulation is given in this paper;the RF signals are got with chip.In the end, PCB pictures are shown.Finally,The Ka-band frequency synthesizer designed in this paper plays high quality in working band,which output power is more than 10dBm. Besides,the phase noise overmatches the system targets.So, there are some reference values in designing wideband frequency synthesizer in millimeterwave .