K-band Integrated Downconverter Design

Downconverter is an important part of microwave integrated receiving systems. No matter the use is of microwave communication, radar, distant control and sensor, and detecting and electronic confrontation, and many other microwave measuring systems, we have to transfer the microwave signal to intermediate frequency using a downconverter.Currently, almost all kinds of microwave systems adapting integrated downconverter, mainly because integrated downconverter occupies the following advantages: less volume, reliable function, mature designing technology, flexible structure, and fitting varied special application. Main oversea chip-supply companies have achieved great success due to their earnest effort with an early beginning on research of GaAs-based MMIC technology. And now these companies have applied this technology to the downconverter. Research institutions and related companies in China also have done much celebrated work. But in microwave field researching staffs have to pay special attention to new theories and manufacturing technics. Due to China's present GaAs technology manufacturing level, there is still a long way to go, especially in the aspects of circuit making and technics. So it is not practical for Chinese researchers achieving monolithic integrated microwave down-converter in a short period of time. Ultimately, the schedule of mixed integrated microwave downconverter comes to the choice.This paper describes the downconverter specifically in the beginning. In this part, the structures of downconverter are analyzed. Considering the advantages of several kinds of structures, the design finally chooses the proper structure. Low-cost, high-reliability MMIC is preferable. According to the request of the user, the ultimate design schedule is determined, including the passive circuit, and active devices. Finally the design completes.