Zheng Zhuang

Wideband Filtering Power Divider With Ultra-Wideband Harmonic Suppression and Isolation

In this paper, a wideband filtering power divider (PD) with ultra-wideband harmonic suppression and isolation is proposed. The dual coupled-line sections are embedded to the conventional quarter-wavelength transmission lines, which helps to extend the passband of the PD. With the introduction of the short-circuit stubs shunted at the output ports and the coupled lines with the open-circuit stubs, the ultra-wide stopband can be implemented more efficiently, thus resulting in five transmission zeros from 2 to 6 GHz. Furthermore, the improved isolation structure with series connected a resistor and a capacitor can be utilized to realize the ultra-wide isolation frequency band. Using a single resistor between two output ports, we have achieved an excellent in-band isolation. For demonstration, a wideband filtering PD operating at 1 GHz with a 20-dB bandwidth of 50% and an ultra-wide stopband better than 20 dB from 2 to 6 GHz is designed, fabricated, and measured. The measured results agree well with the anticipation.

The art of power dividing: A review for state-of-the-art planar power dividers

In this paper, massive state-of-the-art planar power dividers are presented and discussed. The innovations of these superiorly-performanced power dividers lie in the performance breakthrough, physical configurations and function integrations. Eventually, based on the trend presented, the future of the power dividers is predicted. This paper might have inspiration significance to illuminate the way for the development of power dividers.

Three-dimensional multiway power dividers based on transformation optics

The two-dimensional (2D) or three-dimensional (3D) multiway power dividers based on transformation optical theory are proposed in this paper. It comprises of several nonisotropic mediums and one isotropic medium without any lumped and distributed elements. By using finite embedded coordinate transformations, the incident beam can be split and bent arbitrarily in order to achieve effective power division and transmission. In addition, the location of the split point can be employed to obtain unequal power dividers. Finally, several typical examples of the generalized power divider without limitation in 3D space are performed, which shows that the proposed power divider can implement required functions with arbitrary power division and arbitrary transmission paths. The excellent simulated results verify the novel design method for power dividers.

Generalized Dual-Band Unequal Filtering Power Divider With Independently Controllable Bandwidth

In this paper, a novel design method of generalized dual-band unequal filtering power divider (DUFPD) is proposed. Using this method, the power divider (PD) could be designed to realize the dual-band filtering response with arbitrary power division, arbitrary frequency ratio, arbitrary real terminated impedances, independently controllable bandwidth, and excellent isolation. To satisfy these characteristics, a proper dual-band filtering structure is selected to replace the conventional quarter-wave length transmission line in the PD. In addition, a single resistor structure is utilized to obtain effective isolation between the output ports. Furthermore, the complete design procedures and analytical equations of the proposed generalized DUFPD are presented based on the circuit and transmission line theories. To demonstrate the validity of the proposed design method, a DUFPD with different real terminated impedances is designed, fabricated, and measured. We show that there is a good agreement between the simulated and measured results.

A Novel Balanced-to-Unbalanced Complex Impedance-Transforming In-Phase Power Divider

In this paper, a simple and compact planar balanced-to-unbalanced in-phase power divider with arbitrary terminated impedances is proposed based on the coupled-line structure and a single grounded resistor. By using the even-/odd-mode analysis and the traditional transmission-line theory, the complete design procedure and analytical equations are obtained to achieve good performances for differential-mode transmission, common-mode suppression, phase difference, arbitrary terminated impedances, and isolation. For demonstration, two different prototypes with 50-to-

High Selectivity Wideband Bandpass Filter Based on Transversal Signal-Interaction Concepts Loaded with Open and Shorted Stubs

50~\Omega

Arbitrary Multi-way Parallel Mathematical Operations Based on Planar Discrete Metamaterials

matching and complex impedance transformation are designed, fabricated, and measured. Good agreement can be observed between simulated and measured results.

A novel tri-band T-junction impedance-transforming power divider with independent power division ratios

A new design of high selectivity wideband bandpass filter based on transversal signalinteraction concepts loaded with open and shorted stubs is proposed in this paper. Two transmission paths are used to realize signal transmission. Path 1 is composed of a T-shaped structure with shorted stub, and Path 2 consists of two open coupled lines loaded with open stubs. A wide five-order passband and high selectivity stopband with four transmission zeros can be achieved in the proposed filter. Finally, a wideband bandpass filter operating at 3GHz with 3-dB fractional bandwidth of 83.3% (1.55 to 4.05 GHz) is designed, fabricated, and measured. Good agreement between the simulation and experiment is obtained.

Wideband filtering power divider based on coupled-lines and short-circuited stubs

Multi-way parallel mathematical operations along arbitrary transmission paths are constructed based on realizable planar discrete metamaterials in this paper. The introduced method of “computational metamaterials” is used to perform the desired mathematical operations. For producing high-efficiency devices, the function of multi-way parallel mathematical operations is indispensable in advanced analog computers. Therefore, in this paper, we propose the arbitrary transmission paths that can be implemented by the bending of the electromagnetic waves based on the finite embedded coordinate transformations, which has a strong potential to realize the function of multi-way parallel computation. Nevertheless, owing to the inherent inhomogeneous property, metamaterials are difficult to be achieved in nature currently. In order to make it possible for fabricating in practical applications, the planar discrete metamaterial is a promising medium due to its homogeneous property. Numerical simulations validate the novel and effective design method for parallel optical computation.

High Performance Single-Ended Wideband and Balanced Bandpass Filters Loaded With Stepped-Impedance Stubs

In this paper, a novel L network (LN) is presented, which is composed of a frequency-selected section (FSS) and a middle stub (MS). Based on the proposed LN, a tri-band T-junction power divider (TTPD) with impedance transformation and independent power division ratios is designed. Moreover, the closed-form design theory of the TTPD is derived based on the transmission line theory and circuit theory. Finally, a microstrip prototype of the TTPD is simulated, fabricated, and measured. The design is for three arbitrarily chosen frequencies, 1 GHz, 1.6 GHz, and 2.35 GHz with the independent power division ratios of 0.5, 0.7, and 0.9. The measured results show that the fabricated prototype is consistent with the simulation, which demonstrates the effectiveness of this proposed design.