Research On Key Technology Of 110 GHz Frequency Multiplier Chain

In recent years,millimeter wave technology has been widely used in radar and guidance system,electronic countermeasures,broadband communication,radio astronomy,millimeter wave imaging and other fields.Guided by the application of frequency multiplier in millimeter wave imaging system,this thesis studies the 110 GHz frequency multiplier chain,which provides the local oscillator for the imaging system and forms the core components of the transceiver with the mixer.In addition to the completion of the main project,as the following research of millimeter wave multipliers,this thesis also studies a 220 GHz tripler using unbalanced structure.The main research contents of this thesis are as follows:1.The study of 110 GHz frequency multiplier chain.It mainly includes the research and design of a Ka-band multiplier amplifier driver module and 110 GHz tripler based on domestic schottky diode chip and DBES105 a made by the French company of UMS.The Ka-band tripler amplifier driver module is studied as follow.Firstly,according to the current status of commercial MMIC both at home and abroad,the plan of frequency multiplication is dormulated.Then the corresponding RF circuit and DC circuit are designed according to the plan.Finally,the machining,assembling and testing are carried out.The Ka-band tripler amplifier driver module,which had been redesigned,has stable operation and good heat dissipation with the output power of 20-23 dBm and the flatness of ±1.5 dB.The division design method is used to study the 110 GHz tripler.Firstly,the diode working model is established by the method of "3D electromagnetic model + SPICE model".Secondly,the simulation of each passive circuit is completed in the 3D electromagnetic simulation software.Finally,the optimization of the overall circuit of the frequency multiplier is completed by the harmonic balance simulation in ADS.The test results show that the 110 GHz tripler based on the domestic schottky diode has the minimum conversion loss of 16.5 dB and the maximum output power of 4.5 dBm in the range of 90-120 GHz.The 110 GHz tripler based on DBES105 a exhibits an output power of greater than 5 dBm,and conversion efficiency between 2.7% and 6% in the range of 99-120 GHz driven by 21 dBm input power.The maximum output power of the tripler is 8.1 dBm at 110 GHz and the minimum conversion loss is 12.9 dB.The cascading results of the 110 GHz frequency multiplier chain show that the output power is greater than 5 dBm in the range of 100-120 GHz(except 120 GHz)with 8.5-10.5 dBm input power,which can drive the mixer to work normally,meeting the demand of the mixer for the local oscillator source.2.As the extended study of the subject,a 220 GHz tripler is designed based on unbalanced structure.The test results show that the output power is greater than 1 mW in the range of 200-240 GHz with 100 mW driven power,and the conversion efficiency is between 1.07% and 2.46%.The maximum output power is 2.46 mW at 229 GHz with a corresponding minimum conversion loss of 16 dB.