The Intergration Of Power Divider And Filter

Power splitters and filter are two important passive components for wireless communication system. Power divider is a device that can divide the input signal into two or more ways equally or unequally. It can also combine the signals from different ways into one way. Therefore it can be also called combiner. Power dividers include Wil Kinson power splitters, Gysel power splitters, magic T, coupler, hybrid and etc. While the function of filters is to allow a part of frequency signal through smoothly, and inhibit the other part of the frequency of the signal.Power splitters and filter are always used in the same modern wireless communication systems. However, the large sizes of the two components result in a large area of the whole system. In order to realize the miniaturization of the overall design, filters can be integrated with power divider. These integration designs not only can reduce the system’s volume, but also can improve the performance of the system in a certain extent.Based on the study of the integration technology of the power divider and filter, several novel filtering power dividers are present in the paper. They can function as filters and also power dividers with low insertion loss or compact size. The development of the integration technology some of the problems are discussed first in the part 1 of this paper.. Secondly, in view of the problems of the previous technology, some novel structures of filtering power divider are proposed such as:(1) Filtering Wil Kinson power dividers. Three cirtuits are present in this chapter. The first one is realized with dual-functions of filtering and power splitting by adopting five coupling resonators. The second circuit is an unequal power divider by adjusting the coupling strength between resonators. The structure is similar to the first one. For the third circuit, compact size and wide stopband are achieved by using harmonic suppression filter structures to replace the one quarter wavelength lines in Wil Kinson power splitters.(2) Filtering Gysel power divider with arbitrary power ratio. Two filtering networ K with K inverters response are integrated in Gysel power splitters to realize filtering and power division at the same time. More importantly, arbitrary power ratio can be obtained by using this technology. In addition, the out-of-band suppression of the filter structure can be enhanced by the two isolation resistors.(3) Filtering hybrid. Two compact filtering structures with wide stopband are proposed in this chapter. The two filtering structures can function as the K or –K inverter respectively, which can be used to replace a quarter wavelength microstrip line and three-quarters wavelength microstrip line of hybrid. Filtering response with wide stopband and compact size can be realized with this method.