Siw Bandpass Filter

Following the rapidly development of modern microwave technology, specifications of microwave and millimeter-wave circuits and systems become more and more strict. The tendency of modern microwave and millimeter-wave communication systems is small-size, low-weight, reliable, multifunctional and low-cost, mass-production, high-performance and high-yield microwave and millimeter-wave technologies are crucial for developing successful commercial low-cost microwave and millimeter-wave broad systems. Hence, it is necessary to develop novel microwave and millimeter-wave integrated techniques.Substrate integrated waveguide (SIW) is a new kind of microwave transmission line in these years which can be widely used in microwave and millimeter-wave circuit. The substrate integrated waveguide borrow advantages of both of the rectangular waveguide and the microstrip, such as: high Q, low loss just like the rectangular waveguide; small size, low profile, low cost, easy to be integrated like microstrip. The basic structure of SIW is that it use the top and bottom layers of metal together with two row of vias is very small compared with wavelength, the dissipation loss of radiation is very small. It acts like a rectangular waveguide filled with some dielectrics, so components which can be composed by rectangular waveguide can also composed by SIW such as antenna, filter, power divider, coupler, resonator.In this dissertation, a SIW-microstrip transition is studied to easily integrate the SIW components with other microstrip circuits first. Later, some filters are designed by transferring the conventional waveguide cavity filter to the SIW. Finally, some other filters are designed according to some new principles or by using some new structures to the SIW. Such as a half mode Substrate Integrated Waveguide (HMSIW) filter and a Substrate Integrated Waveguide (SIW) filter based on compact microstrip resonating cells (CMRC). All these devices designed have been simulated and optimized by the electromagnetic simulation tools, so that the devices could achieve optimal quality of filtering. Research results are potential valuable for the development of SIW devices.