Research And Design Of The Ka-band Up-conversion Module

MMW transceiver is widely used in radar detection and guidance system.Current advanced technology has realized the integration of the transmitting module,receiving module and the signal source module into a single microwave or millimeter wave chip.However,the stability and reliability of the monolithic integrated system are not high if the operating frequency and the power is high.The military radar communication system requires the stability,reliability and related indexes of the whole circuit system to be high,so the current military communication system is mainly modular.This thesis mainly introduces the specific scheme design,device selection,circuit design,and electromagnetic compatibility design of the Ka-band up-conversion component.The design of the up-conversion component mainly includes the design of the local oscillator module and up-conversion module.The local oscillator module is divided into the first oscillator unit and the second oscillator unit.The local oscillator frequency provided by the first oscillator unit is 4GHz,so it can be directly generated by the phase locked loop.The output frequency range of the second local oscillator unit is 18.8GHz ~22.6GHz.The signal of frequency range of 9.4 GHz ~ 11.3 GHz is first generated by the phase-locked loop,and then the signal of frequency range of 18.8 GHz ~22.6GHz is obtained by a 2 multiplier.According to the specific working index of the up-conversion unit,the superheterodyne frequency conversion scheme is adopted.The key works of this paper are as follows: 1.The basic principle of nonlinear mixing is introduced.A program based on MATLAB software is written,so that the interactive modulation derivation diagram of up-conversion mixer and down-conversion mixer are drawn.The appropriate local oscillator frequency of the component can be determined according to the intermodulation derivation diagram.2.The typical scheme design of up-conversion components is introduced.The superheterodyne up-conversion scheme is determined according to the specific indicators of the components.The local oscillator frequency is determined according to the interactive modulation derived diagram drawn by MATLAB.And the device selection and the allocation of specific indicators of the scheme are carried out.3.The technical indexes of the local oscillator are analyzed,and the scheme design of the local oscillator module is determined.The local oscillator module is divided into 2 parts.The X-band bandpass filter and K-band bandpass filter are designed.4.The overall design of the Ka-band up-conversion component including the circuit design of the up-conversion module,the design of local oscillator module,the design of the electromagnetic compatibility and the design of the power supply circuits is completed.5.The debugging and testing of the Ka-band up-conversion component are completed.The up-conversion module and the local oscillator module are tested and debugged first,and then the unit alignment and testing of the local oscillator module and up-conversion module after the test results met the requirements are conducted.The output of 1 dB compression power of the Ka-band up-conversion component is not less than 13 dBm.The overall gain of the Ka-band up-conversion component is 3.5 dB.The spurious reduction of the Ka-band up-conversion component is greater than 40 dBc under the input power of-30 dBm.The gain flatness of the Ka-band up-conversion component is 2.6 dB.The phase noise indexes are as follows: ?-72dBc/Hz@100Hz,?-88dBc/Hz@1KHz,?-92dBc/Hz@10KHz,?-92dBc/Hz@100KHz.