Universal Design Approach for Multiport Filtering Power Divider

Abstract

This paper presents a universal design approach of multiport filtering power divider with the arbitrary power-division ratio, which is applicable for the designs of the single-ended/balanced circuit or hybrid of them. The power allocation in a specified passband is fulfilled by relying on two key factors in building a filter, i.e., coupling coefficient and external Q-factor (Q e). After synthesis for the bandpass response, the total input/output Q e and the total coupling coefficient at each power dividing level can be determined. Subsequently, according to the desired power-dividing ratio, the coupling coefficient between the two coupled resonators and Q e of each output can be easily determined. Once the parameters for filtering response are fixed, the power allocation can be determined by Q e without effect on the filtering response. Thus, the two functions of bandpass and power dividing can be designed independently, which provides tremendous freedom for the overall design with the arbitrary order of filtering and number of output ports. The proposed topology has several advantages, such as flexibility, cost efficiency, and simple design procedure, which would be a good candidate for multiple-path operation in the current and future MIMO systems. INDEX TERMS Topology, fusion design approach, multiport technology, arbitrary division ratio, filtering power divider.

A direct synthesis method of multi‐port filtering power divider with arbitrary phase shift, power division and reference impedances

“…A fusion topology combining traditional binary‐tree topology and dandelion topology is also proposed in the synthesis process of FPD in Ref. [4]. Additionally, a FPD synthesis method on mixed topology is also presented in Ref.…”

“…Since the traditional method that designs two-port filters and power dividers separately and cascades them through matching circuits, this will always result in a bulky system size as well as the mismatch problems affecting the overall performance. Therefore, research efforts have been continuously devoting to synthesising and designing filtering power divider (FPD), that is, a multi-functional integrated device which can provide both functions of filter and power divider in recent years [1][2][3][4][5][6][7][8][9][10][11][12][13][14]. Among them, the coupling matrix synthesis method is attracting much attention due to its simplicity and wide applicability.…”