Research On W-band Frequency Conversion Module

In the study of millimeter wave technology, whether high sensitivity receiver or high-power transmitter, frequency conversion module is the prime component. Using hybrid integrated circuit is helpful to enhance the flexibility of circuits and save cost. The point of this project is using domestic self-developed MMIC chips to design frequency conversion module in W band. This thesis presents a detail design process of the down-conversion module in W band.At first, according to the project target the structure of down-conversion module in W band is determined to use super heterodyne receiver structure. On the basis of project targets, the circuit frame has been designed to ensure the feasibility of the scheme.Secondly, with the software of HFSS, the passive circuits have been simulated. The microstrip-waveguide transition insertion loss is about 2.4dB in the fRF±2GHz range. The image-reject filter has a 4GHz bandwidth with less than 0.5dB insertion Loss at f0. Active circuits are all domestic MMIC chips insisting of mixer、low-noise amplifier and power amplifier. To figure out the performance of each component in the circuit and ensure the reliability of the down converter, the devices of down conversion module which have great impact on the system have been tested.Finally, the structure of receiver is divided into two layers: microstrip circuit is placed in top layer and bias circuit is kept in bottom layer. This structure can save space and minimize disturbance from high frequency circuit and low frequency circuit. In order to meet different requirements, the filter has been designed as a removable structure in the receiver. In addition, design of circuit should be considered to increase the possibility of recycling the cavity. And the receiver has a dimension of 60mm*37mm*18mm.The down converter has been tested, and the measured results can meet the project targets. In the band of fRF±2GHz, the noise figure is less than 8dB. In the last part, there is a summary about this project. On the basis of the theoretical analysis, some improvement recommendations for the future study have been proposed.