Design Of High-performance Miniaturized Filter Components

With the rapid development of wireless communication technology,it leads to the lack of frequency bandwidth.Filter components,as a good frequency selection device,play an important role in wireless transmission system.To reduce the volume of the communication system,it is important to improve the performance and reduce the size of filter components.Therefore,it is meaningful to design the compact filter components with good performance.Recently,substrate integrated waveguide(SIW)is widely used in the design of microwave devices due to its high quality,low loss,high integration and easy to processing.To realize compact filter components with good performance based on SIW structre,contributions are summarized as below:1.Diplexer with Common Cavity Based on Rectangular SIW Cavity:In this section,the resonant characteristics of the rectangular SIW resonator was analyzed.TE101 and TE201 modes of the rectangular SIW resonator are utilized to reduce the number of resonators.The first resonator of this design is common cavity,working in TE101 and TE201 modes.Comparing to the traditional diplexers,the T-junction is saved to realize minimization.The design has applied for the National Patent.2.Cross Coupling Filter Based on QMSIW:A cross-coupling filter based on QMSIW is designed by reducing resonator size.In this section,a new method is proposed to realize the coupling of QMSIW,for high selectivity of the filter.The filter is compact and has good wide stop-band characteristics.The design has been published in IEEE Electronics Letters.3.Dual-band Filter Based on Stub-Coupling-Line-Loaded HMSIW:In this design,two pairs of coupling lines are loaded on HMSIW for two passbands:2.27GHz-2.46GHz and 4.9GHz?5.1GHz.The insertion loss in the passband is better than-2dB,and the return loss of each passband is better than-17dB.New zeros are produced by introducing hybrid electromagnetic coupling.It improves the selectivity of the design.It has applied for National Patent.4.Diplexer Based on Stub-Coupling-Line-Loaded HMSIW:Two paralleling filters connecting to a T-junction combines to the diplexer.It works with good performance and high isolation.This design produces zeros by loading coupling line.It effectively improves the selectivity of branch filters.It suppresses the harmonic to raise isolation of the diplexer.It has been published in China Microwave Millimeter-wave Annual Conference and has applied for National Patent.