W-band Mixer Technology Research

Millimeter-wave mixers are the key components of millimeter-wave systems. In this thesis, research on W-band hybrid integrated technique is presented, and the first domestic design for a W-band microstrip integrated double balanced mixer and a novel W band balanced mixer are proposed. The simulation, assembling and testing of the mixer are also given.In this thesis, the historical development and future trend of millimeter-wave mixer are introduced. It also introduces different configurations with different transmission line and the advantages of using them. Meanwhile, the conception and index of mixer are given. The theory of mixer using diode is given in detail. The analysis of harmonic balance and transpositional matrix is used to get the formula of conversion loss in the later according to equivalent circuit design the whole circuit .Based on those and the practical needs of some projects, The thesis mainly focuses on two different kinds of millimeter mixers: a W band double-balanced mixer and a W band balanced mixer. In the design of W band double-balanced mixer, a novel structure using Magic-T and two baluns, which all realized by ratrace, is proposed with no crossing of transmission line. RF and LO signals are transmitted to the circuit by Waveguide-to-Microstrip Probe Transitions. A novel DGS lowpass filter is used to purify IF signal. Based on the results of the theory analysis and computer simulation of ratrace, Waveguide-to-Microstrip Probe Transitions, DGS lowpass filter, the structure was designed and manufacture was made. Finally, the index of this mixer was measured.In the design of W band balanced mixer, IF signal is extracted via the fifth port made on the conventional ratrace, and it is sent out through a novel lowpass filter using microstrip stepped- impedance hairpin resonators. This structure is proposed using single-sided substrate with no crossing of transmission line. And it is easy to be manufactured. RF and LO signals are transmitted to the circuit by Waveguide-to-Microstrip finline Transitions. Based on the results of the theory analysis and computer simulation of ratrace, Waveguide-to-Microstrip finline Transitions, novel...