Power Division Ratio Research Articles

Compact power divider based on half mode substrate integrated waveguide (HMSIW) with arbitrary power dividing ratio

Design and realisation of a compact power divider based on half mode substrate integrated waveguide (HMSIW) with an arbitrary power dividing ratio is presented. This design consists of a substrate integrated waveguide (SIW) transition, two bisected HMSIW transitions by a gap, an SIW-to-microstrip transition, and two microstrip feed lines. In addition, a resistor is attached between two HMSIW transitions. To adjust the power division ratio, four parameters are introduced. Furthermore, four graphs are plotted using a three-dimensional electronmagnetic (3D EM) simulator to graphically determine the introduced parameters. In this study, three circuits with power division ratios of 1:1, 1:4, and 1:8 are simulated using the 3D EM simulator and fabricated on a Rogers RO4003C substrate. The results show a good agreement between the simulated and measured results. The measured results display these circuits (1:1, 1:4, and 1:8) have the bandwidths of 70, 36, and 40%, respectively. Moreover, the proposed structures (1:1, 1:4, and 1:8) are compact and their overall sizes are$1.13 \times 1.04\lambda _g^2 $,$0.96 \times 0.91\lambda _g^2 $, and$0.81 \times 0.78\lambda _g^2 $, respectively. These structures have the advantages of the compactness in size, wide bandwidth, high power division ratio (from 1:1 to 1:16), and compatibility with planar circuits.

Modified Wideband Marchand Balun With Tunable Power Division Ratio and Constant Phase

A balun with a wide tunable power division ratio and constant phase across a wide frequency band is presented. The proposed design is a modification of the traditional Marchand balun with a varactor and series resistor loaded at the central point of the two connected pairs of coupled lines. The varactor is used to control the power division ratio at two output ports, whereas the resistor is used to stabilize the power division across a wide operational bandwidth. The achievable power division ratio and differential phase are investigated for different band ranges. A prototype is designed, fabricated, and tested. The results indicate a tuning power ratio range from 1:1 to 3.5:1 across 80% fractional bandwidth (1.2–2.8 GHz) with more than 10 dB return loss and less than 9 $^{\circ}$ differential phase.

Systematic Design Technique for Dual-Band Branch-Line Coupler Using T- and Pi-Networks and Their Application in Novel Wideband-Ratio Crossover

In this paper, a generalized analysis and design methodology of a dual-band branch-line coupler (BLC) is presented. The proposed design, although based on the prevalent method of replacement of various arms of a single-band BLC with an equivalent T-/Pi-network, simplifies the design approach by only replacing either pair of arms and therefore provides four distinct topologies. Closed-form design equations along with insightful comments are reported for all the four topologies of the BLC. A number of cases are investigated to demonstrate the effectiveness of the proposed design for equal and unequal power division ratio and band-ratio ( $= f_{2}/f_{1}$ ). As an application, a novel dual-band crossover as a cascade of BLCs is also presented. While investigating the limitations of previous designs, a strategy to obtain the crossover with so far the widest band-ratio and simple layout is also presented. An unequal power division dual-band BLC and a dual-band crossover are designed which operate at 1/2 and 1/4 GHz, respectively. These designs are validated from the electromagnetic simulations and prototypes implemented on RT/Duroid 5880 substrate.

A Balanced-to-Balanced Network With Unequal Power Division and Wideband Common Mode Suppression

A novel wideband balanced-to-balanced network with unequal power division is proposed in this letter. Two open stubs and half-wavelength transmission lines are used to realize wideband common mode suppression, two ideal double-sided parallel-strip line (DSPSL) 180 $^{\circ}$ phase inverters with isolation resistors are used to realize high isolation for the power dividing output ports. A planar wideband balanced network with bandwidth of 38.6% (power division ratio: $1:2^{2}$ ) for the differential mode and over 113.6% common mode suppression (1.06–3.56 GHz, $| S_{{cc}21,31}| ) is designed and fabricated.

Novel Unequal Dividing Power Divider With 50 Characteristic Impedance Lines

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.

Selective Wireless Power Transfer for Smart Power Distribution in a Miniature-Sized Multiple-Receiver System

In a multiple-receiver wireless power transfer (WPT) system, determining the condition for uniform power distribution at a high transfer efficiency is a challenging issue. In this paper, a selective WPT technique using magnetic resonance coupling (MRC) is introduced for smart power delivery in a multiple-receiver system. The proposed method selectively and exclusively delivers power to only one designated receiver among multiple receivers, eliminating the cross-coupling effect and unbalanced power division problem across the receivers. This is achieved by separating the resonant frequencies of the receivers to isolate the coupling effects between coils. The power division ratio of the receivers is controlled by changing the duration time ratio for power transfer. In this paper, a one-transmitter three-receiver selective MRC system is designed and fabricated. The power distribution is demonstrated under impedance matched condition, showing a power transfer efficiency of 24%–29% at a very small coupling coefficient of 0.01 with a 12-mm-diameter receiver coil. Distance compensation and a one-way communication of time division multiple access are demonstrated for a multiple-receiver system, using the proposed method.

링-하이브리드 커플러를 이용한 가변 전력 분배기 회로

This paper introduces a new variable power divider circuit with an arbitrary power division ratio ranging from to . The proposed power divider circuit consists of one branch-line coupler to be a good input matching characteristic, two variable phase shifters with 90-degree phase variation to be connected two output paths of the branch-line coupler, and one ring-hybrid coupler to combine output signals of two variable phase shifter. The power division ratio between the two output ports of the proposed power divider can be easily controlled by the phase variation of the two phase shifter. The proposed power divider circuit fabricates on laminated RF-35 (h

A Nonstandard Phase-Difference Ring Coupler for Unequal Power Division

ABSTRACTA planar ring coupler with nonstandard phase difference and an unequal power division ratio is proposed in this article. The circuit topology of this coupler is similar to the traditional coupler, which consists of four arms in microstrip implementation. The design parameters of this coupler can be determined easily by closed-form equations. Based on standard microstrip technology, the interrelated constraint between phase difference and realizable power division ratio has been investigated. The fractional bandwidth analysis in terms of phase difference and power division is provided. Two prototypes with this proposed structure, operating at 1 GHz, have been designed, simulated, and implemented using microstrip lines. The measurement shows good agreement with the numerical results, which demonstrates the validity of this design.

FIVE PORTS POWER DIVIDER DESIGNS WITH CONTROLLABLE POWER DIVISION AND SWITCHING CAPABILITIES

Two new 5-port power divider designs capable of controlling the power division ratios between the output ports are proposed. In the first design, the input power is switchable between two pairs of the output ports. This is implemented by terminating the dividers’ two open-ended stubs with varactor diodes. In the second design, the power division is controlled by a single varactor diode that terminates one of the dividers two open-ended stubs. With judicious choice of dc bias voltage, it is possible to realize equal as well as unequal power division ratios between the four output ports. High power division ratios was achieved without the necessity of involving transmission lines with high impedances. It is demonstrated that this design is capable of generating amplitude modulated signals. Simulation and measurement results are presented for the designs to show their power division and matching performance.

Wideband filter-integrated coupled-line coupler with unequal power division and inherent DC-block function

This letter reports a novel single-layer planar coupled-line coupler with multiple prominent advantages. These advantages include compact size, wideband filter-integrated coupling and transmission, unequal power division, flat phase difference, and inherent DC-block function between two arbitrary ports. Eventually, a microstrip prototype with 7.1-dB power-division ratio is implemented for verification, whose fractional bandwidth of 20-dB return loss is 58.4%. © 2016 Wiley Periodicals, Inc. Microwave Opt Technol Lett 58:121–123, 2016

A Thermally Tunable 1 × 4 Channel Wavelength Demultiplexer Designed on a Low-Loss Si3N4 Waveguide Platform

A thermally tunable 1 × 4 channel optical demultiplexer was designed using an ultra low-loss Si3N4 (propagation loss ~3.1 dB/m) waveguide. The demultiplexer has three 2 × 2 Mach-Zehnder interferometers (MZI), where each of the MZI contains two 2 × 2 general interference based multimode interference (MMI) couplers. The MMI couplers exhibit −3.3 dB to −3.7 dB power division ratios over a 50 nm wavelength range from 1530 nm to 1580 nm. The chrome-based (Cr) heaters placed on the delay arms of the MZI filters enable thermal tuning to control the optical phase shift in the MZI delay arms. This facilitates achieving moderately low crosstalk (14.5 dB) between the adjacent channels. The optical insertion loss of the demultiplexer per channel is between 1.5 dB to 2.2 dB over the 1550 nm to 1565 nm wavelength range. Error free performance (BER of 10−12) is obtained for all four 40 Gb/s data rate channels. The optical demultiplexer is an important tool towards building photonic integrated circuits with complex optical signal processing functionalities in the low-loss Si3N4 waveguide platform.

A new design method for a dual band branch line hybrid coupler

This paper presents the design of a dual band branch line hybrid coupler (BLHC) with different power division ratios at two bands. In the proposed design, transmission lines of the BLHC are transformed to

Class of miniaturised/arbitrary power division ratio couplers with improved design flexibility

This study describes a new class of couplers using single-layer microstrip lines that reduce the occupied area, suppress the harmonic components and provide arbitrary power division ratios. It consists of lumped reactances between transmission lines to reach realisable impedances and shorten line lengths. To provide a design guideline, closed-form formulas are derived and five different designs are produced and built to investigate the couplers performance and design accuracy. The simulation results prove to be in good agreement with measurements. More than 70% size reduction with respect to the conventional structures, 12 dB harmonic suppression and high power division ratios (9:1) achieved in various presented branch line, rat race and multi-section Wilkinson dividers. This proposed class of coupler structures can effectively be used in miniaturised and/or arbitrary power division ratio couplers with harmonic suppression.

Generalized dual-band branch-line coupler with arbitrary power division ratios

In this paper, a novel design of generalized dual-band quadrature hybrid with arbitrary power division ratios is presented and investigated. This coupler has a simple structure and can cover a wide range of power division ratios at the two designated frequencies. Exact closed-form equations are derived based on the even–odd-mode analysis method. The proposed structure offers some special features, encompassing: (1) a generalized structure of some recently published papers; (2) isolation in vertical and horizontal directions in the two-dimensional structure; (3) the same sign of the output phase difference for the structure with horizontal isolation and the opposite sign for the structure with vertical isolation; (4) large power division ratios for both vertical and horizontal isolation conditions; (5) large frequency band ratio for both vertical and horizontal isolation conditions; (6) capability of the bandwidth improvement by exploiting coupled lines with small coupling coefficient. For demonstration, a microstrip implementation of a 16:1 dual-band coupler working on 2.45/5.8 GHz is developed. Consistency between simulation and measurement results justifies the proposed design method and its equations.

Dual-band patch quadrature coupler with controllable power division ratios

By employing reactive loading method, a dual-band quadrature coupler, with flexible frequency ratio and controllable power division ratios, is proposed. Stubs with unequal width are loaded on different quadrants of circular sector patch to achieve dual-band operation with simplicity both in structure and design procedure. They also offer the possibility to provide different power division ratios at the two frequency bands for some special cases, and the quadrature phase characteristics can be obtained simultaneously. To verify the proposed configuration, four dual-band quadrature couplers for C and X band applications are designed, fabricated, and measured.

A Design of Power Divider With Negative Group Delay Characteristics

In this letter, the design of power divider with negative group delay (NGD) characteristics is presented. From an analysis, the NGD associated with different transmission paths is found to be identical and obtained by loading resistor connected short-circuited coupled lines with an open-circuited isolation port. The proposed structure is validated by constructing a two-way microstrip line power divider with equal power division ratio, which is centered at 2.14 GHz. The measured results show excellent agreement with simulations and theoretically predicated results. From the measurement, the group delays and magnitudes of $S$ -parameters between the different transmission paths are determined as $-1.16~{\rm ns}$ , $-9.29~{\rm dB}$ , $-1.17~{\rm ns}$ , and $-9.30~{\rm dB}$ . The measured input/output return losses and isolation at center frequency are higher than 28.92 dB, 26.76 dB, and 42.2 dB.

A Novel Adaptive Power Divider for High-Efficiency LTE Doherty Power Amplifier

A novel adaptive power-divider (APD) structure is introduced to overcome the limitations of practical Doherty power amplifiers (DPA). This technique provides a new structure for which the primary distinction from conventional structures is that it adjusts power division ratio to reduce the work load during measurement. Because the base station power amplifiers have a low efficiency due to the power back-off operation, efficiency enhancement techniques become very important. In this article, the efficiency simulation and measurements show that power-added efficiency of 52.5% can be achieved at 11-dB back-off. The power-added efficiency of an adaptive power-divider Doherty power amplifier is 5–10% larger than a conventional Doherty power amplifier. Furthermore, it is shown that this new structure can be used to improve the efficiency of the amplifier and bring a little effect of the third-order inter-modulation distortion.

Analysis and design of a branch‐line balun with high‐isolation wideband characteristics

ABSTRACTThis article presents a design of wideband balun with high isolation using a branch‐line structure. Theoretical analysis of the proposed balun shows that the reflection coefficient characteristics with two transmission poles can be obtained by controlling the characteristic impedances of transmission lines (Zt, Z1, and Z2). The high isolation can be obtained by adding a shunt coupled‐line short stub and resistor (R) between the output ports. The proposed balun was designed at the center frequency (f0) of 2.6 GHz for a current‐mode class‐S amplifier application. The measured results were in good agreement with the simulations, showing that power division ratios were 3.09 dB and 3.14 dB, whereas the return loss was 21.39 dB at the f0 and higher than 20 dB over a bandwidth of 0.98 GHz (1.98–2.96 GHz). The isolation between output ports was higher than 18 dB for the bandwidth of 0.75 GHz (2.21–2.96 GHz). The measured phase difference between the output ports was 180° ± 9° over a frequency range of 2.2–2.98 GHz. © 2015 Wiley Periodicals, Inc. Microwave Opt Technol Lett 57:1228–1234, 2015

Broadband substrate‐integrated waveguide T‐junction with arbitrary power‐dividing ratio

A novel broadband substrate-integrated waveguide (SIW) T-junction with an arbitrary power-dividing ratio is proposed. Three inductive posts are designed to adopt flexibility for the equal output T-junction to obtain a wide impedance bandwidth. To realise the unequal power-dividing ratio over a wide bandwidth, the SIW coupler is integrated with corner structures and a novel T-junction structure is formed. Three T-junctions with different power division ratios (1:1, 1:4 and 1:8) at a centre frequency of 6 GHz are simulated, fabricated and measured. The measured bandwidths are 60, 53 and 63.3%, respectively.

Compact Unequal Power Divider with Filtering Response

We present a novel unequal power divider with bandpass responses. The proposed power divider consists of five resonators and a resistor. The power division ratio is controlled by altering the coupling strength among the resonators. The output ports have the characteristic impedance of 50 Ω and impedance transformers in classical Wilkinson power dividers are not required in this design. Use of resonators enables the filtering function of the power divider. Two transmission zeros are generated near the passband edges, resulting in quasielliptic bandpass responses. For validation, a 2 : 1 filtering power divider is implemented. The fabricated circuit size is 0.22λg × 0.08λg, featuring compact size for unequal filtering power dividers, which is suitable for the feeding networks of antenna arrays.