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The transmission line forms of the power divider mainly include microstrip line, stripline, waveguide structure, etc, among which the connection between stripline structure and other transmission lines is a challenge. In response to this challenge, this paper proposes a hybrid transmission line one-to-four power divider with a stripline opening and directly connected to microstrip line. Through the analysis of the basic principles of the power divider via electromagnetic simulation software, the power divider is modeled and simulated, and the design method is verified by physical verification. The power divider has an input and output reflection coefficient of less than-10 dB and the isolation of 15 dB in the frequency range of 2~6 GHz, which achieves a good design effect. The bending design of the power divider meets the design requirements of miniaturization. This paper provides certain reference value and significance in the future research.

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A new design of a 1:2 and 1:4 microstrip power divider is proposed using finite defected ground structure (FDGS), in this paper. In order to design the presented divider, Wilkinson and Gysel power divider are used simultaneously. T-shaped and L-Shaped resonators are applied to decrease the circuit size and suppress eliminate unwanted harmonics. Moreover, to have more size reduction, Wilkinson power divider is located inside of the Gysel divider. The center of operating frequency is about 2.75 GHz (from 2.6 to 2.9 GHz). The designed power divider suppresses four harmonies and reduces the size of power divider about 88%. [ABSTRACT FROM AUTHOR]

Copyright of Railway Signalling & Communication Engineering is the property of Railway Signalling & Communication Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

To many with an interest in British military swords the name of Pillin will be very familiar. Yet, for a firm which traded for at least 65 years there is little information available about its activities beyond a few bare dates and addresses often quoted from the same sources. The original source of much of this information is unclear and some of this now appears questionable. In writing this article my intention is to provide a more comprehensive account of the Pillin dynasty. By examining what new evidence may be available I hope to evaluate and revise contemporary wisdom regarding Pillin's operations. In conducting this research during a global Covid-19 pandemic, amid national and local lockdowns, I am restricted in source material but have relied heavily on sources available online. Such methodology carries its own risks, there are gaps in the available datasets and frustratingly, transcription errors can both hamper searches and offer false positive matches. Nevertheless, with the rise in popularity of ancestry research, new data sources are constantly being made available. In today's world of social media and online resources we have ready access to data of which researchers even 15 years ago could only have dreamed. Information regarding sword cutlers, such as their trading dates and addresses, is of particular interest as it can help to correctly date a sword. This in turn can assist with identifying an original owner. In the case of British blades, etched with the owner's initials or a family crest, cross referencing with the Army lists will often provide multiple possible candidates over the lifetime of a sword pattern. Accurately identifying the year of manufacture can significantly assist in narrowing the field of potential matches against any one set of initials. A desire to identify the original owners of some of my own collected swords, and to assist others to do the same, provided the seed of motivation for my research into the Pillin dynasty. I hope this article provides a useful platform for additional research. [ABSTRACT FROM AUTHOR]

The paper introduces a class of two-way, 3 dB narrowband power dividers (combiners), closed on complex termination impedances, that generalizes a number of topologies presented during past years as extensions of the traditional Wilkinson design. Adopting even-odd mode analysis, we demonstrate that, under very broad assumptions, any axially symmetric reactive 3-port can be designed to operate as a 3 dB two-way power divider, by connecting a properly designed isolation impedance across two symmetrically but arbitrarily located additional ports. We show that this isolation element can be evaluated by a single input impedance or admittance CAD simulation or measurement; moreover, an explicit expression is given for the isolation impedance. The theory is shown to lead to the same design as for already presented generalizations of the Wilkinson divider; further validation is provided through both simulated and experimental case studies, and an application of the theory to the design of broadband or multi-band couplers is suggested.

In this article, a class of dual‐band filtering power dividers is proposed with simultaneous realization of good designable port‐to‐port isolation. A filtering branch, including two cascaded stub‐loaded half‐ wavelength resonators and coupled‐line sections, are introduced together with the proposed isolation network to simultaneously achieve controllable bandwidth, frequency ratio in dual‐band power division, as well as the port‐to‐port isolation. To construct dual‐wideband power division, two coupled multimode resonators could be used to form the filtering branches, while the proposed isolation network with additional open stub at each output port is utilized to obtain a wide port‐to‐port isolation band. Theoretically, a design method for analyzing the dual‐band frequency response of the power division is presented, while a dual‐ or wide‐band isolation is achieved by introducing multiple transmission zeros in the S32‐magnitude. Finally, two prototype power dividers on the microstrip‐line structure are designed and fabricated. The simulated and measured results agree well with each other, which verify the theoretical predications. [ABSTRACT FROM AUTHOR]

A spiral-coupled-line-based Ka-band (26.5–40 GHz) CMOS Wilkinson power divider with a shunt capacitor (C) at the input and a shunt RC (or C) between the outputs is reported. The spiral coupled line, i.e., two noninverting spiral transmission lines (TLs) with magnetic coupling, has a positive mutual inductance. This leads to a significant TL-length reduction (from about λ/7 to λ/12) for a specific TL series inductance. At 33 GHz, the power divider achieves prominent S11 of −21.5, S22 of −22.1, S33 of −22.1, S32 of −26.1, S21 of −4.063, and S31 of −4.052 dB. The corresponding amplitude imbalance (AI) and phase difference (PD) are −0.011 dB and −0.336°, respectively. Moreover, S11 is smaller than −10 dB for 0–45.3 GHz, corresponding to 137.3% fractional bandwidth (FBW). S32 is smaller than −10 dB for 24.1–40.2 GHz, covering the Ka-band and corresponding to 48.8% FBW. The power divider occupies a normalized area of 1.2 ×10−4λ02, one of the smallest normalized chip areas ever reported for millimeter-wave power dividers. [ABSTRACT FROM AUTHOR]

A diplexer with different-frequency power dividers cascaded to its output ports can split a signal into different frequency bands for power dividing functions. However, the design of a diplexer usually requires two different frequency filters. This paper presents three new microstrip diplexing power dividers (DPDs) to achieve duplexing power division without requiring additional filters. Moreover, to increase selectivity, each of the proposed DPDs has the flexibility of adding a dual-band filter to its input port. In particular, the proposed DPDs have matching circuits integrated in the dividers, enabling each divider with imaginary input impedance to reach the required open condition; this is achieved by designing a 50-Ω transmission line of appropriate length or a quarter-wavelength (λ/4) transmission line.

In this paper, 4:1 Wilkinson and Gysel combiner are designed and simulated for high-power applications. Since Wilkinson power combiner provides broad bandwidth characteristics and low insertion loss, it can be an appropriate candidate for realizing the required power combiner. The fabricated combiner provides a maximum insertion loss of about 0.5dB and Max S11 and S22 of about -10 dB in the frequency band of 8-9.2 GHz. It was designed in such a way that it can easily be tuned to compensate phase mismatch between four different inputs with a precision of about 15 degrees. [ABSTRACT FROM AUTHOR]

This paper presents four compact lumped-element Wilkinson power combiners (WPC) operating at 5 GHz in 28-nm bulk CMOS. To minimize the chip area, the inductances in the designs are implemented using mutually coupled coils. Two designs use star inverting coupled coils (SICC), while the other two employ delta noninverting coupled coils (DNICC). One of the two SICC-based designs (and similarly for the DNICC-based designs) incorporates a second harmonic (2f0) trap to lower the total harmonic distortion and reduce the required inductances by 25%, further reducing the circuits footprint. A design methodology for effectively exploiting the mutual coupling and nullifying the coupling parasitics is presented. The coupling parasitic in the DNICC-based design is exploited to provide the WPC isolation resistance, resulting in a lumped-element WPC requiring only three components: a coupled coil and two capacitors. The measurement and simulation results are presented to confirm the theory validity. The SICC-based WPC with an area of 0.13 mm2 achieved input return losses (RL) >17.5 dB, output RL > 11.8 dB, isolation >11.2 dB, and insertion losses (IL) <1.5 dB across 3.5–5.4-GHz frequency range. Its variant with a 2f0 trap achieved, from 3.5–5.35 GHz, input RL >18.2 dB, output RL >11.6 dB, isolation >11 dB, IL <1.4 dB, and peak 2f0 rejection of 18 dB at 10.2 GHz in an area of 0.13 mm2.The DNICC-based WPC with an area of 0.11 mm2 achieved input RL and isolation >10 dB, output RL >15.3 dB, and IL <1.2 dB across 4.1–5.45-GHz frequency range. Its variant with a 2f0 trap achieved, from 4.3–5.3 GHz, input RL and isolation >10.1 dB, output RL >14.6, IL <1.2 dB, and peak 2f0 rejection of 23 dB at 10.4 GHz in an area of 0.09 mm2. [ABSTRACT FROM AUTHOR]

This paper presents the design of broadband two way equal power divider in microstrip medium with defected ground structure suitable for broadband communication systems. Quarter wave broadside coupled lines are used in the place of conventional transformers widely used in the popular Wilkinson power dividers. The proposed power divider structure takes the advantage of top and bottom layers of the microstrip medium to create broadside coupled line configuration using defected ground plane. The floating conductor in the bottom layer plays a critical role in achieving the band select characteristics. Experimental results of two way equal power divider designed using the proposed structure has been verified against the full wave simulations. The isolation between the paths is more than 20dB and the return loss at each port is better than 15dB across the desired band of 3GHz to 8GHz. [ABSTRACT FROM AUTHOR]

This letter presents a low-loss compact 60-GHz power divider/combiner (PD/C) for phased array systems. It is based on the Wilkinson power divider and employs coupled inductors with a shunt capacitor for low insertion loss and compact design. The power divider with a coupled inductor reduces the insertion loss by 0.4 dB at 60 GHz. The insertion loss is less than 0.7 dB, and the return loss is better than 10 dB over a range of 50–67 GHz. The measured isolation of the fabricated PD/C is up to 28 dB at 67 GHz. The fabricated PD/C has a compact core size of 0.0012 mm2. To the best of our knowledge, this power divider achieves the lowest insertion loss and the smallest core area of all published 60-GHz Wilkinson PDs/Cs. [ABSTRACT FROM AUTHOR]

In this paper, three designs of Wilkinson Power Divider (WPD) at 9.0 GHzcenter frequency are proposed. The first design is 2-way in-phase equal poweroutputs implemented on the Roger RT-duroid 6006, PTFE ceramic, relativepermittivity = 10.2 r e and thickness of substrate material h = 0.365mm. Thesecond design is 4-way and the third design is 8-way in-phase equal power dividersare implemented on the same substrate. The third design is a new shape of 8-wayWPD consists of feeder connected with four WPD via cut cortex rhombus toachieve matching with inputs. All designs are simulated by using CAD(Microwave Office 2000). The simulation results demonstrate that the powerdivider works well at assigned operating frequency with compact size. Lowinsertion and high isolation are achieved.

La resolución de sistemas de ecuaciones lineales es sin duda el problema más importante en Matemática Aplicada. Es importante en sí mismo y también porque es un paso intermedio en la resolución de muchos otros problemas de gran relevancia. La eliminación Gaussiana es hoy en día el método estándar para resolver este problema en un ordenador y, además, fue el primer algoritmo numérico para el que se realizó un análisis de errores de redondeo. En 1948, Alan Turing publicó un artículo de gran relevancia sobre este tema: “Rounding-off errors in matrix processes” (Quart. J. Mech. Appl. Math. 1, pp. 287-308). En este artículo, Turing formuló la eliminación Gaussiana en términos de la factorización LU de una matriz e introdujo la noción de número de condición de una matriz, que son dos de las nociones más fundamentales del Análisis Numérico moderno. Además, Turing presentó un análisis de errores de la eliminación Gaussiana para matrices generales que influyó profundamente en el espíritu del análisis de errores definitivo desarrollado por Wilkinson en 1961. El trabajo de Alan Turing sobre la eliminación Gaussiana aparece en un periodo fascinante del Análisis Numérico moderno. Otros gigantes de las matemáticas como John von Neumann, Herman Goldstine y Harold Hotelling también realizaron investigaciones sobre la eliminación Gaussiana en la década de 1940-50. El objetivo de estos investigadores era encontrar un método eficiente y fiable para resolver sistemas de ecuaciones lineales en los ordenadores modernos que estaban desarrollándose por entonces. En aquella época, no estaba claro en absoluto si utilizar la eliminación Gaussiana era una elección adecuada o no. El propósito de este artículo es revisar, a nivel básico, las contribuciones realizadas por Alan Turing y otros investigadores al análisis de errores de la eliminación Gaussiana, el contexto histórico de esas contribuciones y su influencia en el Análisis Numérico moderno.

This paper proposes and presents a class of substrate integrated waveguide (SIW) power dividers/combiners based on a modified Wilkinson architecture. The proposed design consists of a ring-type circuit of \(1.5~\lambda _{g}\) length with three waveguide ports. Impedance variation without affecting cutoff frequency and integration of isolation resistance are the two major limitations in connection with the design of SIW Wilkinson structures. Central ring part with different thickness ensures different impedance in the first proposed scheme while the half-mode SIW in the second option. As for the second limitation, the optimal configuration of integrating the isolation resistance is studied. A version without resistance is also examined using a broad-wall series slot. To validate the proposed concept, a bilayered circuit with standard Printed circuit board prototype was fabricated and measured. A table summarizing performances of all the proposed circuits shows a bandwidth of around 25% at the 10 dB reference. A negligible additional insertion loss is observed. The proposed design techniques are found useful at millimeter-wave frequencies where reduced physical dimensions make a circuit configuration suitable for low-cost implementation. This concept is also valid for rectangular waveguide counterparts. [ABSTRACT FROM AUTHOR]

Abstract: EOF-17 (EOF: element organic framework) represents a new member of the EOF family based on phosphorus connected via an organic biphenyl. It is characterized by a specific surface area (BET) of up to 646m2/g and a thermal stability of up to 360°C. As a heterogeneous analog of PPh3 the permanent infiltration of rhodium and palladium complexes is demonstrated. EOF-17 infiltrated with rhodium was successfully tested in the transfer hydrogenation of cyclohexanone. [Copyright &y& Elsevier]

A generalized model of a two-way dual-band Wilkinson power divider (WPD) with a parallel LC circuit at midpoints of two-segment transformers is proposed and compared with that of a conventional two-way dual-band WPD with a parallel LC circuit at the ends of two-segment transformers. The sum of power reflected at an output port and power transmitted to an isolation port from another isolation port in the proposed divider is smaller than that in the conventional divider. Therefore, wide bandwidths for S22, S33, and S32 can be expected for proposed dividers. In the case of equal power division, frequency characteristics of return loss at output ports and isolation of the proposed divider are wider than those of the convention one. The resonant frequencies of LC circuits in the proposed divider and a conventional divider are equal; however, the inductance L used in the proposed divider is always smaller than that in the conventional divider. Design charts and calculated bandwidths as a function of frequency ratio from 1 to 7 are presented. In experiments, two symmetrical and two asymmetrical circuits were fabricated. The experimental results showed good agreement with theoretical results. [ABSTRACT FROM PUBLISHER]

Current English law has few controls on the involuntary treatment of persons detained under the Mental Health Act 1983. In 2001, R (Wilkinson) v. Broadmoor Special Hospital Authority provided some hope that, in conjunction with the Human Rights Act and the European Convention on Human Rights (ECHR), meaningful substantive and procedural standards for compulsory psychiatric treatment might be developed, but that hope has not been fulfilled. Using Wilkinson and the ECHR jurisprudence as a starting point, this article considers when, if at all, compulsory psychiatric treatment might be justified. In particular, it considers the difference between the ‘appropriateness’ standard of the English legislation and the ECHR requirement of ‘therapeutic necessity’, the requirements for appropriate procedure and appropriate legislative clarity, how the courts should deal with disagreements among treating physicians, and the relevance of the capacity and best interests of the detained person. [ABSTRACT FROM PUBLISHER]

A generalized two-way two-section dual-band Wilkinson power divider with two absorption resistors and its size-reduced model are presented. Design equations for dual-band and arbitrary power division are derived from modified even- and odd-mode analysis. The frequency ratio of the lower and upper band frequencies must be lower than three. The channel bandwidth is presented as a function of frequency ratio with mathematical expressions. A coupled line section is introduced to reduce circuit size based on the assumptions of linear phase characteristics and equal phase velocities of the even and odd modes. Two two-way dual-band power dividers, one three-way planar dual-band power divider, and one size-reduced dual-band power divider were fabricated. Experimental results were in good agreement with predicted values. [ABSTRACT FROM AUTHOR]

In this letter, we propose an $N$-way unequal power division Wilkinson power divider (PD) with physical output port separation. These PDs employ isolation impedances at arbitrary positions within quarter-wave-long transmission lines, and hence both electrical isolation and physical separation can be obtained between output ports. Design equations are derived, meeting the impedance matching and isolation requirements of the PD. The fabricated 2-way (1:2) and 3-way (1:2:1) PDs operating at 2.0 GHz exhibit excellent insertion loss, return loss, and isolation performance with the output ports physically separated. [ABSTRACT FROM PUBLISHER]

This letter presents a fully differential and integrated transformer-based Wilkinson power divider with a broad bandwidth, low loss, high isolation, and an ultra-compact form factor. Two differential transformers connected in parallel serve as the impedance transforming and power combining network in the proposed Wilkinson power divider. Shunt capacitors are added between the output ports for matching and isolation enhancement. A proof-of-concept transformer-based Wilkinson power divider is designed at 60 GHz and implemented in a standard 130 nm SiGe BiCMOS process with the core chip area of 270\ \mu\textm \times 107\ \mu\textm and the simulated 1 dB-magnitude fractional bandwidth of 64% at the 60 GHz center frequency. Measurement results of 4 independent samples demonstrate the passive loss of 1.32 dB at 62 GHz with standard deviation of 0.1 dB and the peak isolation of 28 dB at 65 GHz with magnitude and phase imbalance within 0.2 dB and 5 ^\circ, respectively. [ABSTRACT FROM PUBLISHER]

In this letter a novel power divider (PD) structure with uniformed characteristic impedance lines and a fixed isolation resistor equal to source and load impedances has been proposed. Unlike traditional power dividers, the electrical lengths of the uniformed 50 $\Omega$ branches are the only parameters that need to be adjusted to achieve any required power division ratios, which makes it a flexible and adaptable layout for most desires. Arbitrary power division ratio, especially large dividing ratio that is difficult to achieve by conventional Wilkinson PD, can be obtained easily by applying the proposed structure. For verification, the measured results of a 2 : 1, a 4 : 1 and a 9 : 1 PDs operating at 3 GHz are shown in this letter. [ABSTRACT FROM PUBLISHER]

It is common practice to design multiway power dividers by interconnecting two-way power dividers. Transmission lines are used to link the two-way dividers. This paper investigates the performance of the interconnected power divider and the effects of the interconnecting transmission lines. In particular, it will be shown that the performance of multiway dividers constructed by interconnecting even-number-section two-way dividers deteriorates significantly as the number of output ports increases. The interconnecting lines can be used to improve the performance of such dividers. [ABSTRACT FROM AUTHOR]

The insoluble Wilkinson catalyst RhCl[P(m-C6H4SO3)Na)3]3 changes from inert to very active by supported on mesoporous material SBA-15, and the catalyst is stable, easy to separate from products, clean, and can be reused directly. This catalyst combines the advantages of homogeneous catalysts and heterogeneous catalysts very well. [ABSTRACT FROM AUTHOR]