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Microwave passive component design is of particular interest to radio frequency (RF) scholars and engineers. Although a plethora of studies have been carried out over multiple decades, designing high-frequency structures that offer high performance still heavily relies on heuristic methods and even rules of thumb. Thus, the process is often inefficient, and outcomes are not guaranteed. This article proposes a novel cascaded convolutional neural network (CNN) model to speed up the design process of planar microwave passive components. Given target behavior specifications, our proposed neural network model can quickly and accurately suggest proper component structures for single or multiple frequency bands. The feasibility and reliability of our model are validated here by both electromagnetic (EM) simulation and a fully instrumented implementation. The experimental results demonstrate that the proposed model can design planar passive components, including two-port matching networks and three-port power dividers. Moreover, our model provides passive component topologies that are fundamentally different from canonical number-limited templates and, therefore, yields novel architectures for passive microwave components. It also facilitates rapid passive components design flow for targeted electrical behavior within a limited board area. The proposed cascaded CNN model and the associated methodologies in this article are generic and, thus, can be easily extended to the design of any symmetrical planar microwave passive components.

In this article, a simple and effective method based on the metamaterial concept is proposed to achieve very high isolation between the output ports of a millimeter-wave power divider (MWPD). The proposed MWPD is designed for use in 5G applications (28–32 GHz). In order to increase the isolation, three metamaterial rows are used, each row containing eight proposed unit cells. These metamaterial unit cells are loaded between two dielectric layers. By using this method and without isolating resistors, isolation is improved by more than 36 dB, as compared with a prototype power divider in which no metamaterial element was used. The maximum measured isolation is 43 dB at 30 GHz. The final dimensions of the proposed MWPD are $8 \times 8\,\,\times0.582$ mm3 or $0.9\,\,\lambda _{\mathbf {g}} \times 0.9\,\,\lambda _{\mathbf {g}} \times 0.08\,\,\lambda _{\mathbf {g}}$ where $\lambda _{\mathbf {g}}$ is the guided wavelength at 30 GHz. The simplicity of design, its compactness, and most importantly, high isolation between output ports without any lumped resistor are the key advantages of the proposed MWPD.

Time-frequency synchronization plays an important role in the construction of solar radio telescopes (such as heliograph and interferometry). In the development of a synchronization system, time-frequency signal is divided and transmitted to each antenna in an array, therefore, the performance of the signal splitting devices determines the quantity of the data. To address this situation, we designed a frequency transmitting system, and conducted a test to compare the phase difference among outputs (10 MHz - 1.4 GHz), and the deterioration of the frequency stability (10 MHz - 1GHz) brought by different splitting devices (fiber splitter and power divider). The following results had been obtained: 1) Phase difference introduced by both fiber splitter and power divider can be restricted in a range of ±4°, and the fiber splitter is rather stable, which indicate that a better imaging effect of heliograph can be achieved when using fiber splitters. 2) Frequency stability deterioration get better (worse) with increasing temperature for fiber splitter (power divider) in the testing frequency range for a short-time sampling (100 ms), and for a long-time sampling (10 min), the frequency stability of different devices is determined by both temperature and signal frequency. By estimating the SNR, the performance of optical splitter is found to be slightly better than power splitter. This article provides a basis for the selection and compensation of frequency transfer system components for integrated aperture heliograph, and provide a feasible solution of the construction of low-cost radioheliograph.

We present an all-dielectric chiral photonic crystal that guides the propagation of electromagnetic waves without backscattering for dual bands. The chiral photonic crystal unit cell is composed of four dielectric cylinders with increasing inner diameter clockwise or anticlockwise, which leads to chirality. It is demonstrated that the proposed chiral photonic crystal can generate dual band gaps in the gigahertz frequency range and has two types of edge states, which is similar to topologically protected edge states. Hence, the interface formed by the proposed 2D chiral photonic crystal can guide the propagation of electromagnetic waves without backscattering, and this complete propagation is immune to defects (position disorder or frequency disorder). To illustrate the applicability of the findings in communication systems, we report a duplexer and a power divider based on the presented all-dielectric chiral photonic crystal.

This paper proposes a miniaturized multi-section power divider with parallel resistor and capacitor isolation circuits. Each of the section transmission lines constituting the proposed multi-section power divider has a length less than a quarter wavelength and the impedance of the transmission lines can be controlled within a certain range while avoiding high impedance. In addition, each circuit connected between the transmission lines consists of a parallel resistor and capacitor to satisfy the matching and isolation characteristics between output ports. To validate the proposed power divider, two circuits at a frequency of 2 GHz were designed with two- and three-section dividers. In comparison to a conventional power divider, the proposed divider showed broadband performances with a small structure.

A Ku-band Substrate Integrated Waveguide power divider is proposed. In this work, the SIW power divider is designed with T-junction configuration. The SIW technique enables the power divider to have low insertion loss, low cost and features uniplanar circuit. An additional of metallic via hole is added in the center of the junction to improve the return loss performance of the Tjunction SIW power divider. The simulated input return losses at port 1 are better than 27 dB, and features equal power division of about -3.1 dB ±0.4 dB at both output ports across frequency range of 13.5-18 GHz. The SIW power divider is fabricated, and the measurement results show acceptable performances. Since there are some losses contributed by the SMA connector of the fabricated SIW power divider prototype, an additional SIW transmission line is simulated and fabricated to analyze the connector loss.

In this paper, a tri-band impedance transformer (TBIT) using a coupled line and a dual-band to tri-band transformer is proposed, which can transform frequency-dependent complex impedances to a real-value impedance. In order to explain how to determine circuit parameters, closed-form equations are derived in detail. Based on the TBIT, a compact T-junction power divider (TTPD) is designed. This TTPD works at three different frequencies with independent controllable power division ratios. Simple steps to design the TTPD are listed. To demonstrate the validity of the theory, this paper exhibits a prototype operating at 2, 4.4, and 5 GHz with different power division ratios. Moreover, the simulated and measured results prove that this TTPD has the features of tri-band operation, independent controllable power division ratios, enhanced bandwidths, and small size.

This paper presents a novel wide-band filtering three-port coupler with inherent DC-blocking function, which is simply comprised of a power divider with wideband filtering function and a broadband phase shifter with a modified coupled line. For demonstration, a designed prototype operating at 3 GHz is simulated, fabricated, and measured. From the simulated and measured results, the coupler shows a 49% filtering bandwidth with 12-dB return loss and 90° ± 590°phase shifting. The amplitude imbalance between the two output ports is less than 0.5 dB. The all-passband isolation is below -13 dB and the 25.7-dB upper stopband rejection is up to 5.4 GHz. Good agreement between the simulated and measured results validates the proposed idea. Hence, the proposed coupler is well suited for the applications of wideband, filtering, and single-layer circuitry integration.

This paper proposed an integrated conical conformal array antenna (CCAA) for versatile application to the unmanned aerial vehicles. The CCAA consists of five flexible linear gradient subarrays with a uniform circumferential arrangement around the conical surface. It is also embedded with a pyramid reflective back-cavity (PRBC) within the conical carrier. The implementation for the three different elements of the linear gradient subarray toward impedance match and high isolation was investigated, and their identity resonant frequency (9.8 GHz) principle was developed and demonstrated. Furthermore, the PRBC was presented to improve the radiation null of the elements. A numerical 5-bit phase shifter manipulating phase difference of 72° was then combined with an 8-way power divider to obtain a fixed beam with a half power bandwidth (HPBW) of less than 24°, which indicated the backward endfire direction (θ = 180°) in terms of three circumferential arrays (R#X). Finally, the measurements with the aid of the designed phase shifter and power divider (model SHPDW4-040140S) were conducted. The experimental results show one omnidirectional coverage (360°) in the H-plane through the switching working mode of the elements with a wide scanning solid angle (≥72°) when these elements of the subarray hold an identity resonant frequency and exhibit a uniform performance in the point-to-point communication. The measurements of a narrow HPBW of less than 27.5° and the gain over 10.7 dBi in the endfire direction of the three circumferential arrays show great potential in backward blind space detection simultaneously.

A power divider (PD) with a wide stopband and simple symmetric structure using open- and short-ended stubs is analyzed and implemented in this paper. In the proposed power divider, for the first time, the output resistor is divided into two sections and open- and short-ended stubs are used between the resistors. The incorporated open- and short-ended stubs have resulted in a controllable bandwidth for the proposed PD, which resulted in 40% of the fractional bandwidth considering 3 dB attenuation of insertion loss. The proposed PD operates at 2 GHz, which shows more than 20 dB attenuation for the return and isolation losses. In addition, the obtained insertion loss at the operating frequency is approximately 0.3 dB, which shows a minor loss, and also, high isolation is achieved in the device. Moreover, 20 dB and 30 dB attenuation levels have been achieved for second and third harmonics. The results show high performance for the proposed power divider.

A 16-pixel terahertz (THz) receiver front-end working at room temperature was designed, built, and measured in this paper. The designed receiver front-end is based on the antenna-coupled AlGaN/GaN high-electron-mobility transistor (HEMT) THz linear detector array (TeraLDA) and a 16-way THz power divider. The local oscillator (LO) signal is divided by the power divider into 16 ways and transmits to the TeraLDA. Each detector contains a planar unified antenna printed on a 150 μm-thick sapphire substrate and a transistor fabricated on AlGaN/GaN heterostructure. There are 16 silicon hemispheric lenses located on the TeraLDA to increase the responsivity of the TeraLDA. The focus of each lens is aligned in the center of the TeraLDA pixels. Depending on different read out circuits, the receiver front-end could work in homodyne and heterodyne modes. The 16-way power divider is a four-stage power divider that consists of fifteen same 2-way dividers, and was fabricated by bulk silicon microelectromechanical systems (MEMS) technology to achieve low insertion loss (IL). This designed receiver front-end could be a key component of a THz coherent focal plane imaging radar system, that may play a crucial role in nondestructive 3D imaging application.

A power divider plays a significant function in antenna’s feeding network. Many types of power divider exist yet there are only a few existing studies of Wilkinson power dividers at high frequencies (28 GHz) for 5G communications systems. This paper presents a tapered 2-way Wilkinson power divider that operates in Malaysia's 5G wireless communication band (28 GHz). CST microwave studio is used to design, simulate, and optimize the tapered 2-way Wilkinson divider. The simulation results show resonance around 23.5-37.9 GHz. The operating frequency of 28 GHz resulted in power division with a 3.2 dB insertion loss and has an isolation of 19.21 dB. The design can be made wideband with equal power division at each output port by adding an extra resistor along the tapered line to reduce output return loss and isolation, as demonstrated in this paper.

In the design of a microstrip power divider, there are some important factors, including harmonic suppression, insertion loss, and size reduction, which affect the quality of the final product. Thus improving each of these factors contributes to a more efficient design. In this respect, a hybrid technique to reduce the size and improve the performance of a Wilkinson power divider (WPD) is introduced in this paper. The proposed method includes a typical series LC circuit, a miniaturizing inductor, and two transmission lines, which make an LC branch. Accordingly, two quarter-wavelength branches of the conventional WPD are replaced by two proposed LC branches. Not only does this modification lead to a 100% size reduction, an infinite number of harmonics suppression, and high-frequency selectivity theoretically, but it also results in a noticeable performance improvement practically compared to using quarter-wavelength branches in the conventional microstrip power dividers. The main important contributions of this technique are extreme size reduction and harmonic suppression for the implementation of a filtering power divider (FPD). Furthermore, by tuning the LC circuit, the arbitrary numbers of unwanted harmonics are blocked while the operating frequency, the stopband bandwidth, and the operating bandwidth are chosen optionally. The experimental result verifies the theoretical and simulated results of the proposed technique and demonstrates its potential for improving the performance and reducing the size of other similar microstrip components.

A 28 GHz power amplifier (PA) using CMOS 0.18 μm Silterra process technology for milimeter wave applications is reported. Maximizing the power added efficiency (PAE) and output power are achieved by optimize the circuit with power divider and cascade configuration. In addition, reverse body bias is also employed for realizing excellent PAE and power consumption. A three stage CMOS PA with power combiner is designed and simulated. The simulation results show that the proposed PA consumes 62.56 mW and power gain (S21) of 8.08 dB is achieved at 28 GHz. The PA achieves saturated power (Psat) of 12.62 dBm and maximum PAE of 23.74% with output 1-dB compression point (OP1dB) 10.85 dBm. These results demonstrate the proposed power amplifier architecture is suitable for 5G applications.

This paper shows a compact fully integrated six-port Substrate Integrated Waveguide (SIW) operating at Ku-Band frequency range. The SIW six-port is formed by combining two SIW power dividers and two SIW couplers, having the benefit of no additional termination is required as this topology has no excessive port. To achieve the optimized design of the six-port, both of the key components; power divider and coupler are primarily designed, fabricated, and measured individually. Y-junction topology is employed on the power divider structure to achieve a compact size. In turn, the coupling coefficient of the two output ports of the SIW coupler are improved by shifting the position of a row of several vias located at the side wall center closer to the side wall. The simulated six port performance provides an advantage of wide bandwidth within Ku-Band across 13 to 17 GHz with a return loss better than 12 dB and transmission coefficient of 7±1.5 dB. The simulated and measured results show good agreement thus validating the prototype. The SIW six-port can find its application in designing a six-port.

A dual-layer 3-dB substrate-integrated waveguide power divider/combiner is designed, fabricated, and tested. Very good input and output matching as well as high isolation are exhibited over a measured 50% fractional bandwidth when a 10-dB reference level is considered. A completely shielded design significantly reduces insertion losses when compared to the majority of other state-of-the-art architectures. This device can be integrated with multilayer planar circuits, and it is fully compatible with the standard printed-circuit board technology.

Based on the concept of conventional Gysel power divider, a novel concept of half-mode substrate integrated waveguide (HMSIW) Gysel power divider was reviewed and developed, by simply combining a traditional HMSIW power divider and a microstrip isolation network. The proposed concept was reviewed, investigated, and analyzed thoroughly, after that, $Y$ -type, $T$ -type, and Parallel-type HMSIW Gysel power divider were designed and analyzed, respectively. Furthermore, based on Parallel-type design, a developed version using two isolation networks was proposed for frequency bandwidth enhancement. All the four prototypes were fabricated and measured for verification and comparison. The good electrical performances and compact configuration indicate the advantages of the proposed concept and an excellent candidate for high power-handling HMSIW/SIW circuits or systems.

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- $50~\Omega $ matching and complex impedance transformation are designed, fabricated, and measured. Good agreement can be observed between simulated and measured results.

In this paper, performance analysis of switching and matching stubs was done to a reconfigurable power divider with Single Pole Double Throw (SPDT) switch function. Two designs (Design A and Design B) with different positions of switches and matching stubs were proposed. Rogers RO4350 (er=3.48, h=0.508 mm) was used in this analysis as a substrate material with copper thickness of 0.035 mm. The performance analysis was carried out based on insertion loss, return loss and isolation parameters. The simulated results showed that Design B had a better performance than Design A and was able to work as a reconfigurable power divider with SPDT switch function.

Very high-power and high-efficiency microwave applications require waveguide structures to combine/divide the power from/to a variable number of high-power solid-state devices. In the literature, among the different waveguide configurations, those capable of providing the maximum output power show a limited relative bandwidth. To overcome this limitation, in this paper a full-band (40%) waveguide power divider/combiner specifically designed for high-power applications (up to several kW) is presented. The proposed structure uses an evolved turnstile junction with a standard rectangular waveguide common port, rotated 45&deg, with respect to its central axis, to divide/combine the signal to/from the four output/input rectangular ports. The inclusion of an oversized central cavity together with circular and rectangular waveguide impedance transformers at the common port allows the achievement of a full-band operation with excellent electrical performance, while maintaining a very simple and compact configuration. Only two layers of metal are required for the physical implementation of this structure in platelet configuration. A prototype has been designed covering the full Ka-band (26.5&ndash, 40 GHz), showing an excellent measured performance with around 30 dB of return loss, 0.18 dB of insertion loss, and less than 1.5&deg, of phase imbalance.

Power divider and combiner structures are the necessary and crucial passive components in order to reach high power levels for the microwave applications. The improvements in the RF/Microwave systems in the past decades have led to increasing demand for the compact, high performance power divider/combiners. In this thesis, four-way offset power divider/combiner, two-way ring power divider/combiner, three-way phase shifted Wilkinson power divider/combiner and four-way corporate power divider are designed at 8-12 GHz frequency band by using miniaturization techniques. Their analytical solutions are presented, and design procedures are explained using Advance Design System (ADS) software environment. These divider and combiner structures are fabricated using Bilkent University Nanotechnology Research Center (NANOTAM)’s Gallium Nitride (GaN) on Silicon Carbide (SiC) process. Details of the fabrication steps are demonstrated. On-wafer measurements of the designed divider and combiner structures are performed in NANOTAM laboratories are presented. Measurement and simulation results for insertion losses, input and output losses and isolations of the output ports are investigated for each power divider/combiner structures. Comparison of the measurement and simulation results are examined in detail. Güç bölücü ve birleştirici yapılar, mikrodalga uygulamalarında yüksek düzeyde güçlere ulaşabilmek için gerekli ve kritik pasif elementlerdir. Son yıllardaki RF/Mikrodalga sistemlerindeki gelişmeler, yüksek kaliteli, yüksek performanslı güç ayırıcı/birleştiricilere olan talebin artmasına neden olmuştur. Bu tez çalışmasında, dört yönlü ofset güç bölücü/birleştirici, iki yönlü halka güç bölücü/birleştirici, üç yönlü faz kaydırmalı Wilkinson güç bölücü/birleştirici ve dört yönlü birleşmiş güç bölücü, minyatürleştirme teknikleri kullanılarak, 8-12 GHz frekans bandında dizayn edilmiştir. Analitik çözümleri ve tasarım prosedürleri Advance Design System (ADS) yazılımı kullanılarak incelenmiştir. Bu bölücü ve birleştirici yapılar Bilkent Üniversitesi Nanoteknoloji Araştırma Merkez’inin (NANOTAM) Silisyum Karbür (SiC) tabanlı Galyum Nitrür (GaN) prosesi kullanılarak üretilmiştir. Fabrikasyon detayları adım adım gösterilmiştir. Tasarlanan bölücü ve birleştirici yapılar, NANOTAM laboratuvarlarında ölçülmüştür. Her güç bölücü/birleştirici yapı için ekleme kayıplarının, giriş ve çıkış geri dönüş kayıplarının ve çıkış portlarının yalıtımının ölçüm ve simülasyon sonuçları incelenmiştir. Ölçüm ve simülasyon sonuçlarının karşılaştırılması detaylı olarak sunulmuştur.

A broadband rectangular waveguide to substrate integrated waveguide power divider for hybrid beam forming networks is presented. Rectangular waveguide symmetric E-plane irises are used to realize a multi-section matching network. A hybrid circuit and full-wave design procedure are described and adopted to synthesize three matching networks with one, two, and three irises, progressively increasing the bandwidth and exceeding the state of the art in the last two cases. Three proof-of-concept prototypes are manufactured and tested to validate the design procedure. Good agreement between simulated and measured performance confirms the validity of the proposed solution.

Although all existing air-filled substrate integrated waveguide (AFSIW) topologies yield a substrate-independent electrical performance, they rely on dedicated, expensive, laminates to form air-filled regions that contain the electromagnetic fields. This paper proposes a novel substrate-independent AFSIW manufacturing technology, enabling straightforward integration of high-performance microwave components into a wide range of general-purpose commercially available surface materials by means of standard additive (3-D printing) or subtractive (computer numerically controlled milling/laser cutting) manufacturing processes. First, an analytical formula is derived for the effective permittivity and loss tangent of the AFSIW waveguide. This allows the designer to reduce substrate losses to levels typically encountered in high-frequency laminates. Then, several microwave components are designed and fabricated. Measurements of multiple AFSIW waveguides and a four-way power divider/combiner, both relying on a new coaxial-to-air-filled SIW transition, prove that this novel approach yields microwave components suitable for direct integration into everyday surfaces, with low insertion loss, and excellent matching and isolation over the entire [5.15–5.85] GHz band. Hence, this innovative approach paves the way for a new generation of cost-effective, high-performance, and invisibly integrated smart surface systems that efficiently exploit the area and the materials available in everyday objects.

This paper presents the size miniaturized and harmonic suppressed lossless 1:4 T-junction unequal power divider using an open complementary split ring resonator (OCSRR). By embedding the OCSRR structure in the microstrip transmission line, slow wave effect is introduced and thereby size reduction is achieved. The dimensions of OCSRR are optimized to reduce the length of high impedance and low impedance quarter-wavelength transmission lines. In our design high impedance line length is reduced to 58.6%, and low impedance line length is reduced to 12% when compared to the conventional quarter wavelength lines. The proposed power divider is having small dimensions of 0.18 λg × 0.33 λg and is 51.94% smaller than the conventional unequal power divider.

The design of the quadrature phase shift keying (QPSK) modulator by using a multi-port network is proposed in this article for the use in wireless communication applications. The multi-port network is in the form of multilayer microstrip-slot technology. This multi-port network is composed of three 3-dB rectangular-shaped directional couplers with virtual stubs and an equal power division divider with in-phase characteristic. The design is performed by applying a full-wave electromagnetic simulation software, CST Microwave Studio (CST MWS). Keysight’s Advanced Design System (ADS) is applied in analyzing and evaluating the QPSK constellation of the proposed modulator. This comparatively small size of proposed design has been fabricated, and its wideband performance of 2 to 6 GHz is verified.

This paper presents the characterization and operation of an alternative device, which is known as multi-port reflectometer to measure the reflection coefficient of any device under test (DUT). Its configuration is formed by two power dividers (D) and four couplers (Q). The characterization is evaluated through the centres of power circles that also known as q-points. Its operation in the reflection coefficient measurement is tested by using three DUTs. The reflectometer’s good performance and wideband operation are proven between the frequency band of 1 and 6 GHz via the practical hardware measurement in the laboratory.

This paper present the compact power divider integrated with coupler and microstrip cavity filter for x-band surveillance radar system. These modules consist of several devices (splitter, filter and coupler) it is integrated in a single module aims to reduce the loss in the joint connectors. The bandpass filter is use microstrip cavity filter for operating on X-Band Frequency and deployed on RT/duroid 5880. The power divider and coupler is designed using quarter wavelength transformer. A theoretical analytical circuit model will be presented, from the theoretical model; a compact integrated module will be designed and simulated. The proposed compact integrated module is small in dimension and performs a compact size. The compact integrated devices design on X-Band frequency is simulated and the result is presented.

The design and test of 5-way high power divider operating at P-band for the airborne Synthetic Aperture Radar (SAR) system of DLR is presented. Distinctive features are high bandwidth, high power and an unequal power split on the 5 output ports.

Presents a power-divider architecture whose characteristics are adjustable independently at two frequencies. The circuits uses a single semiloop stepped-impedance resonator filter coupled to the input and output lines. A specific methodology has been developed to design such a circuit.

Date of Conference: 1-6 June 2014 Conference Name: 2014 IEEE MTT-S International Microwave Symposium, IMS 2014 We analyze the bandwidth capability of a divider with a series RLC circuit at the isolation arm. Analytical expressions for optimal component values are given. Bandwidth limiting effect of the pad capacitances of the chip resistors is analyzed. These parasitic capacitors are compensated by the proposed structure. Broadband characteristic of the new divider is verified by experimental results.

CIMITEC This paper proposes a dual-band power divider operating at GHz frequencies and implemented by means of impedance transformers (also called inverters) based on lattice networks and transmission line sections. The dual-band functionality of the proposed device is achieved thanks to the composite right/left handed (CRLH) behavior of the impedance transformers, able to provide −90° and +90° phase shift at the first and second design frequencies, respectively, of the divider. By using such combination of transmission line sections and lattice networks, the characteristic impedance of the impedance transformers is roughly constant over wide bandwidths, with the results of broad operating bands. To demonstrate the possibilities of the approach, a prototype device is designed, fabricated and characterized.

Mikrodalga sistem, genellikle, süzgeç, bağlaştırıcı, güç bölücü gibi temel elemanlarlatasarlanır. Mikrodalga frekanslarda dalgaboyu toplu eleman büyüklüğüylekıyaslanabilir olduğu için dağınık elemanlar kullanılır. Belirli frekanslara kadarmikroşerit yapılar kullanılabilir, fakat yayılma kaybı arttıkça hantal ve pahalıolan dalga kılavuzları kullanılır.Son yıllarda, malzemeye gömülü dalga kılavuzu (MGDK) tabanlı yapılar, azmaliyetli, hafif ve verimli yüksek frekans karakteristikleriyle birçok araştırmacınındikkatini çekmiştir. MGDK, dalga kılavuzunun baskı devre gerçeklemesidir.MGDK, malzemenin alt ve üst yüzeyindeki iletkenler ve iki dizi halinde metalikdeliklerle tasarlanır. Bu tezde MGDK yapılarını kullanarak, iris tipinde bantgeçiren süzgeçler tasarlanmıştır, analiz edilmiş ve doğrulamak için üretilmistir.Daha sonra, literatürdeki tümler yarıklı halka rezonatör (TYHR) ve dambıltipinde deforme toprak yapısı (DTY) gömülü süzgeçler incelenip benzetimledoğrulanmıştır. Literatürdeki farklı süzgeç yapıları incelendikten sonra, yeniMGDK tabanlı, ikinci harmoniğin mikroşerit hat altındaki dambıl tipi DTY ilebastırıldığı bant geçiren süzgeç önerilmiştir. Süzgeç üretilmiş ve üretim sonuçlarıbenzetim sonuçlarıyla örtüşmüştür.Son olarak, literatürdeki MGDK tabanlı güç bölücüler ve metalik deliklerinaçık-devre uçlu çeyrek-dalgaboyu çubuklarla yapıldığı oluklu MGDK (OMGDK)yapılar incelenmiştir. OMGDK yapısı literatürdeki güç bölücülere uygulanarakyüksek izolasyonlu yeni bir güç bölücü tasarlanmış ve üretilmiştir. Üretimsonuçları benzetim sonuçlarıyla örtüşmüştür. A microwave system is, in general, designed by using fundamental componentssuch as filters, couplers, dividers, etc. Due to the fact that wavelength becomescomparable with lumped element dimensions, at microwave frequenciesdistributed elements are used for building these components. Microstrip baseddevices can be used up to certain frequencies. However, when radiation lossincreases, waveguide based devices are used which are bulky and costly.Recently, substrate integrated waveguide (SIW) based devices have attracted theattention of many researchers due to low cost, lightweight and efficient high frequencycharacteristics. SIW is the printed circuit realization of a waveguide. SIWis fabricated on a dielectric material with top and bottom sides are conductors,and two linear arrays of metallic vias form the side walls. In this thesis, by usingSIW structure, iris type bandpass filters are designed, analyzed and fabricated forverification. After that, complementary split ring resonator (CSRR) and dumbbelltype defected ground structure (DGS) etched filters that are available inthe literature are investigated and verified with simulations. Having investigateddifferent filter topologies in the literature, a novel SIW based bandpass filter isproposed, where its second harmonic is suppressed using a dumbbell type DGSunderneath the microstrip feed line. The filter is demonstrated with a fabricatedprototype, where the simulated and measured results agree well. Furthermore,SIW based power dividers available in the literature and the corrugated SIW(CSIW) architecture which uses open-circuit ended quarter-wavelength stubs insteadof vias as the sidewalls, are investigated. CSIW architecture is implementedto a power divider structure available in the literature and a novel CSIW basedhigh isolation power divider is designed and demonstrated with a fabricated prototype.Good agreement between simulated and fabricated results are observed. 110

A 2 x 2 microstrip patch antenna array fed by a substrate integrated waveguide (SIW) feeding network for 24-GHz radar applications is proposed in this letter. Themicrostrip patches are aperture-coupled with the feeding network consisting of a perpendicular coax-to-SIW transition and two Y-junction power dividers. The antenna design is performed in the full-wave electromagnetic solver ANSYS HFSS and verified by measurement. At the operation frequency 24 GHz, a fabricated prototype has a gain of 11.1 dBi and a low sidelobe level below -22 dB in the E-plane and -33 dB in the H-plane.

In this paper, a six-port receiver analog front-end structure based on a Wilkinson power divider and three hybrid couplers is presented, which has been implemented in a multilayered, meandered manner, yielding a size reduction of about 78% compared to a planar design. The measured S-parameters of the new design are in good accordance with simulated S-parameters of the planar structure. System simulations with an orthogonal frequency division multiplexing signal show the suitability of the design for six-port communications receivers.

Negative-refractive-index transmission-line (NRI-TL) metamaterials and introduced and their fundamental properties are described. Following this, various applications using NRI-TLs are shown and their salient characteristics are shown. First, a broadband microstrip balun is shown, then a broadband 1:4 power divider, followed by a series-fed linear dipole array that exhibits reduced beam squinting, then a leaky-wave antenna with reduced beam squinting is presented and finally an electrically small ring antenna is shown that exhibits vertical linear polarization. 2007

A number of new antenna-related applications that have recently been developed at the University of Toronto based on the concept of negative-refractive-index transmission-line metamaterials are reviewed. These include non-radiating phase-shifting lines that can produce either a positive or a negative phase-shift while exhibiting a broadband linear phase response, as well as compact and broadband series power dividers and associated planar series-fed printed dipole arrays with reduced beam-squinting. Moreover, a fully printed electrically small ring antenna featuring vertical polarisation and good radiation efficiency is also described. © 2007 The Institution of Engineering and Technology. 1 1 12 22

A metamaterial 1:4 series power divider that provides equal power split to all four output ports over a large bandwidth is presented, which can be extended to an arbitrary number of output ports. The divider comprises four nonradiating metamaterial lines in series, incurring a zero insertion phase over a large bandwidth, while simultaneously maintaining a compact length of λ 0/8. Compared to a series power divider employing conventional one-wave-length long meandered transmission lines to provide in-phase signals at the output ports, the metamaterial divider provides a 165% increase in the input return-loss bandwidth and a 155% and 154% increase in the through-power bandwidth to ports 3 and 4, respectively. In addition, the metamaterial divider is significantly more compact, occupying only 2.6% of the area that the transmission line divider occupies. The metamaterial and transmission line dividers exhibit comparable insertion losses. © 2005 IEEE. 15 11 808 810

The planar realization of beam forming networks for active antenna systems in satellite communication requires small and high performance power splitters. The microstrip radial line power divider seems to be a suitable structure for this purpose, because, under certain hypothesis, insures an equiphase and equiamplitude power splitting. A design procedure which assures the realization of optimized n- way radial line dividers is proposed and the corresponding design charts are given. Moreover good agreement between experimental and theoretical data from different sources is demonstrated.

Power dividers are required and used in a wide variety of applications. It is often sufficient to halve the power and divide it evenly between two branches. However, if one branch requires more power than the other, a divider with an unequal power ratio is needed. In the presented work, an equal and an unequal Gysel divider were designed, simulated and measured. Compared to other Gysel splitters, the ones demonstrated here have advantages in size, isolation and losses.

This paper presents a dual-band feed network for K-/Ka-Band phased array transceiver modules. It is intended to interface receive and transmit beamformer chips and the antenna elements with the remaining front-end circuitry. The whole arrangement consists of two printed circuit boards (PCBs) which are mounted on both sides of an aluminum 1:4 rectangular waveguide (RWG) power divider/combiner. It includes transitions from grounded coplanar waveguide (GCPW) to RWG. These are self-diplexing and thus an integral part of the whole feed network. Due to the RWG aluminum body, this integration approach offers adequate heat transfer capabilities and increased space for surface mount devices (SMDs). Because of its high frequency selectivity, image reject filters in the Rx-path can be dispensed with. The manufactured passive demonstrator exhibits reflection coefficients below -10 dB from 18.7 GHz to 20.5 GHz (Rx-band) and from 29.2 GHz to 30.5 GHz (Tx-band) and an insertion loss of $3.9\ \text{dB} < \text{IL} < 4.8\ \text{dB}$ and $2.8\ \text{dB} < \text{IL} < 3.6\ \text{dB}$ at these frequencies. Although the Rx- and the Tx-paths share the same RWG divider/combiner, they are diplexed with an isolation of more than 30 dB in both bands.

The component presented in this work combines three functionalities, i.e., a waveguide transition, frequency separation, and power division. A rectangular waveguide (RWG) serves as common 20/30 GHz port. The signals are diplexed into two 20 GHz and four 30 GHz grounded coplanar waveguides (GCPWs). The required 3 dB and 6 dB power division ratios are achieved reactively and by exploiting symmetries. Both passbands feature a -10 dB reflection bandwidth of more than 1.2 GHz, an insertion loss below 1.3 dB, an isolation exceeding 25 dB, and an amplitude imbalance of less than 1 dB. The component occupies only 9 x 9 mm2 on a single layer printed circuit board (PCB) and is thus suitable for application in highly integrated phased array front-ends.