Design And Implementation Of High Performance Miniaturized Filtering Power Divider

In modern wireless communication systems,power divider is widely used in feed network of antenna arrays,power amplifiers,mixers,and so on.Research on miniaturization and integration of high-performance filtering power divider is becoming more and more popular.In this paper,the research topic is the high-performance miniaturized filtering power divider.The implementation technology of out-of-band interference suppression,in-band isolation and the calculation of microstrip circuit is researched.The main research contents are divided into four parts.The first part introduces the basic theory of the filtering power divider.Firstly,this part presents the basic concepts of the transmission line and the design method of the filter.Secondly,the basic theoretical analysis of structurally symmetric power divider is illustrated based on the odd and even mode theory.Finally,the theory of slow wave structure which leads to wide stopband is analyzed.Moreover,the hybrid microstrip Tstub/defected ground structure cell with strong slow wave effect is shown in detail.In second part,slotline,shorted stub and defected ground structure are employed in the filtering power divider with wide stopband.By proposing a new type of defected ground topology,power division,filter and wide stopband are achieved.Then,in order to increase the slope rate around the passband skirt,the slotline and shorted stub are adopted.Moreover,high stopband attenuation can be achieved utilizing the slotline.Furthermore,the isolation within a wide stopband can be promoted with the slotline.The measured and simulated results are in good agreement.In third part,a compact filtering Wilkinson power divider exhibiting the high isolation and rejection level within a wide stopband is proposed.It utilizes the defected ground structure with strong slow wave effect to obtain wide stopband.Then,the openstub loaded coupled line is employed to improve the selectivity of the passband.Meanwhile,the theoretical calculation and model simulation are carried out,which are in good agreement.For demonstration,based on the previous theory a new miniaturized power divider is implemented.The measured results match well with the simulation.The fourth part presents the wideband power divider with high isolation.High isolation is achieved by the innovative isolation network.Additionally,two open-ended stubs are attached in stepped impedance lines not only improve its frequency selectivity but also control bandwidth.Besides,the theoretical calculation and model simulation are introduced in detail.It is found that the calculated results agree well with the simulated ones.For validation,a wideband power divider is fabricated and analyzed.