Broadside Coupling Research Articles

Broadband CMOS Schottky-Diode Star Mixer Using Coupled-CPW Marchand Dual-Baluns

A broadband CMOS Marchand dual-balun using stacked broadside couplers for low odd-mode impedance with surrounded ground planes for high even-mode impedance is employed to achieve a high coupling coefficient needed for a Marchand dual-balun. The demonstrated Marchand dual-balun using 0.18- $\mu \text{m}$ CMOS technology is designed at 30-GHz center frequency with an insertion loss of 11.5- and 10-dB input return loss bandwidth of over 120%. The bandwidth of 1-dB amplitude imbalance and 10° phase difference are over 100%. A broadband CMOS Schottky-diode star mixer is implemented with two Marchand dual-baluns at RF and local oscillator (LO) ports. As a result, the Schottky-diode star mixer shows conversion loss of 14 dB, LO-to-RF isolation of 26 dB, LO-to-IF isolation of 45 dB, and RF-to-IF isolation of 42 dB within 27-GHz operating bandwidth, respectively.

Compact Wideband Broadside-Coupled Microstrip-Slot Bandpass Filter for Communication Applications

<p>This paper proposes a compact size design of wideband bandpass filter (BPF). The broad-side coupling microstrip-slot technique is used to accomplish a good passband response with very low insertion loss across a wideband frequency range. The BPF that is designed using Rogers RO4003C substrate shows a good performance with the respective maximum reflection coefficient and insertion loss of -10 dB and 1.2 dB between 0.92 GHz and 5 GHz. This type of BPF filter is useful in any communication applications.</p>

UWB 90° phase shifter based on broadside coupler and T‐shaped stub

An UWB 90° phase shifter based on broadside coupler and T-shaped stub is proposed. Its operation mechanism is explained by the equivalent circuit. The measured results exhibit that the bandwidth is 126.7% with phase deviation within ±6°, and the insertion loss is <1.8 dB over the frequency band from 2.2 to 9.8 GHz. Comparison shows that the proposed design not only achieves the widest bandwidth, but also has low insertion loss and small phase difference. This design is a good candidate for UWB applications due to its low cost, planar structure, and convenient installation.

Folded Multilayer C-Sections With Large Group Delay Swing for Passive Chipless RFID Applications

An origami-based multilayer structure suitable for passive chipless radio frequency identification applications is presented in this paper. Contrary to the existing multilayer designs where metallic via is used for the interconnections, the proposed technique uses the folding of the structure designed in a flexible substrate. Thus, the multilayer structure is obtained from a thin printed circuit board that is folded to give the desired 3-D structure. The proposed structure consists of cascaded commensurate transmission line sections (also known as C-sections) coupled at alternative ends. The group delay (GD) characteristic of the C-sections is utilized for encoding. Broad side coupling of the structure is exploited here, which enables large GD with higher frequency selectivity. It is proved that to produce the same amount of delay, linearly cascaded C-sections demands five times more number of C-sections than that of a multilayered structure, which also signifies the factor of miniaturization of the proposed design. A coding capacity of 6 and 12 b is estimated from the simulation, respectively, for single group and multigroup of multilayered C-sections in the allowed industrial, scientific, and medical (ISM) bands. This shows for the first time that frequency domain chipless technology can be compatible with the use of ISM bands. It also allows a coding capacity of 43 b in the ultra-wideband band which is comparable with the EAN 13 barcode.

Broadband Microstrip-to-Microstrip Vertical Transition Design

This letter presents a broadband microstrip-to-microstrip vertical transition. Basically, the transition is based on broadside coupling between the upper and lower microstrip patches through a wide slot etched on the ground plane. In order to enhance bandwidth of the transition, a patch introducing a half wavelength resonance into the passband is added on the ground plane. A demonstrator transition has been designed, fabricated and measured. Results show that a frequency range of 2.8 to 8.5 GHz (referred to return loss of 10 dB) is obtained.

Compact Planar Loop–Dipole Composite Antenna With Director for Bandwidth Enhancement and Back Radiation Suppression

A wideband and unidirectional loop-dipole composite antenna with a planar structure is proposed. The antenna includes a half-wavelength dipole and a one-wavelength loop that are printed on different sides of a substrate. To control the radiation characteristics of each element separately, the dipole is fed using a coaxial cable, whereas the loop is fed using offset broad-side coupling. To overcome the low front-to-back ratio (FBR) at lower and upper frequencies of the band, where the loop-dipole mode is not dominant, while maintaining a compact size, a parasitic strip is located in the vicinity of the loop. The strip acts as a director for the dipole at the low frequencies and for the loop at the high frequencies and thus significantly improves the FBR at those frequencies. The antenna achieves a wide fractional operating bandwidth of 49% at 0.7-1.15 GHz, a size reduction of more than 50% compared with recent similar designs, stable gain with a peak value of 4.8 dBi, and a minimum FBR of 11 dB across the operating bandwidth. Owing to its compact and planar structure, lightweight, simple fabrication, and stable radiation characteristic, it can be utilized in various wireless applications operating at the ultrahigh-frequency band.

Band Notched UWB-BPF Based on Broadside Coupled Microstrip/CPW Transition

ABSTRACTA planar band notched ultra-wideband (UWB) bandpass filter based on broadside coupling of microstrip/co-planar waveguide (CPW) transition is proposed and implemented. The UWB filter topology is made up of microstrip lines on the top coupled in broadside fashion to an open ended CPW in the ground plane. Dual narrow notches at 5.2 and 7.9 GHz are implemented by etching two meander shaped defected ground structures in the CPW under the microstrip lines. A wideband stopband for improved isolation is obtained with the suppression of spurious harmonics by the attenuation poles generated by the spur line structures embedded in the input and output feeding lines. The proposed structure exhibits good frequency characteristics and is of compact size.

Coplanar waveguides loaded with symmetric and asymmetric multisection stepped impedance resonators: Modeling and potential applications

ABSTRACTThis article is focused on the analysis and modeling of coplanar waveguide (CPW) transmission lines loaded with multisection stepped impedance resonators (MS‐SIRs), transversely etched on the back substrate side. The considered structure consists of a CPW loaded with a 5‐section SIR (5S‐SIR) with wide (capacitive) central and external sections cascaded with narrow (inductive) sections. The general case of a 5S‐SIR with arbitrary lengths and widths of the different sections is considered. The structure is described by a pair of inductively coupled grounded series resonators coupled to the line through the capacitance of the central 5S‐SIR section. If the structure is symmetric, the transmission coefficient exhibits a single transmission zero. Hence, these structures can be used as notch filters exhibiting wide bandwidths, provided the inductance of the 5S‐SIR can be made small, and the capacitance can be enhanced by virtue of the broadside coupling. However, if symmetry is broken, two notches separated a distance that depends on the level of asymmetry and inductive coupling appear. Therefore, these structures are also useful for the implementation of differential sensors and comparators. The proposed model is validated through parameter extraction and experiment, and a proof‐of‐concept of a comparator is reported. © 2016 Wiley Periodicals, Inc. Microwave Opt Technol Lett 58:722–726, 2016

Экспериментальное подтверждение возможности защиты радиоэлектронной аппаратуры от сверхкороткого импульса за счет его разложения в С-секции с лицевой связью

Экспериментальное подтверждение возможности защиты радиоэлектронной аппаратуры от сверхкороткого импульса за счет его разложения в С-секции с лицевой связью

Crosstalk Impact of Periodic-Coupled Routing on Eye Opening of High-Speed Links in PCBs

Minimizing costs in printed circuit board layouts has led designers to use two signal layers between the reference planes, which introduce broadside coupling. Additionally, due to the fiber weave effect, designers route signal traces in a zig-zag fashion rather than in straight lines. This type of routing tends to be roughly periodic between the victim and the aggressor. The periodic-coupled routing creates periodic resonances in the near-end crosstalk and nulls in insertion loss (THRU) transfer functions as a consequence of Floquet modes. Due to the periodic resonances, the crosstalk is aggravated, which reduces the signal to crosstalk ratio. This study quantifies the effect of crosstalk due to periodic routing. In addition, design guidelines based on the angle of routing, length of period, and signaling speeds are formulated for designers using statistical bit error rate eye analysis.

A Miniaturized Dual-Band MIMO Antenna &lt;newline/&gt;for WLAN Applications

This letter reports on a compact planar dual-band Multiple-Input and Multiple-Output (MIMO) antenna for Wireless Local Area Network (WLAN) applications. The proposed antenna primarily consists of two meandered monopole radiators that are decoupled by introducing a folded Y-shape isolator element and it is shown that the edge coupling between the radiators and isolator introduces the resonance at the lower band. The miniaturization is achieved by passing the signal on to the bottom layer where a meandered line conductor introduces a broadside coupling with the radiator, originating the higher band resonance. The antenna operates between 2.4 GHz to 2.5 GHz and 5.45 GHz to 5.65 GHz with an isolation of more than 25 dB and 15 dB, respectively. The antenna measures only $19 \times 23~\hbox{mm}^2$ .

A miniature coupled-line-based 3-dB directional coupler using GaAs PHEMT process

A novel complementary-conducting-strip (CCS) coupled-line (CL) design is proposed to achieve compact size by applying two-dimensional layout and standard gallium-arsenide (GaAs) thin-film technology. To obtain high coupling and satisfy the design rules of GaAs process, mixed-couple mechanism with edge and broadside coupling are also used. A CCS CL-based Ka-band 3-dB directional coupler is fabricated using WIN 0.15-μm GaAs pseudomorphic high electron mobility transistor technology. Experimental results show that the proposed directional coupler can cover the entire Ka-band (26–40 GHz) with through and coupling of approximately 3.7 ± 0.25 dB, and isolation of better than 13 dB. In addition, the phase difference between the two output ports is approximately 90° ± 5°. The occupied area of the prototype (without I/O networks) is only 220 × 220 μm2. © 2015 Wiley Periodicals, Inc. Int J RF and Microwave CAE 26:21–26, 2016.

Push-Push Voltage Controlled Dielectric Resonator Oscillator Using a Broadside Coupler

A push-push voltage controlled dielectric resonator oscillator (VCDRO) with a modified frequency tuning structure using broadside couplers is investigated. The push-push VCDRO designed at 16 GHz is manufactured using a low temperature cofired ceramic (LTCC) technology to reduce the circuit size. The frequency tuning structure using a broadside coupler is embedded in a layer of the A6 substrate by using the LTCC process. Experimental results show that the fundamental and third harmonics are suppressed above 15 dBc and 30 dBc, respectively, and the phase noise of push-push VCDRO is -97.5 dBc/Hz at an offset frequency of 100 kHz from the carrier. The proposed frequency tuning structure has a tuning range of 4.46 MHz over a control voltage of 1?11 V. This push-push VCDRO has a miniature size of 15 mm×15 mm. The proposed design and fabrication techniques for a push-push oscillator seem to be applicable in many space and commercial VCDRO products.

Reflectarray Antennas for Dual Polarization and Broadband Telecom Satellite Applications

A reflectarray antenna with improved performance is proposed to operate in dual-polarization and transmit-receive frequencies in Ku-band for broadcast satellite applications. The reflectarray element contains two orthogonal sets of four coplanar parallel dipoles printed on two surfaces, each set combining lateral and broadside coupling. A 40-cm prototype has been designed, manufactured, and tested. The lengths of the coupled dipoles in the reflectarray cells have been optimized to produce a collimated beam in dual polarization in the transmit and receive bands. The measured radiation patterns confirm the high performance of the antenna in terms of bandwidth (27%), low losses, and low levels of cross polarization. Some preliminary simulations at 11.95 GHz for a 1.2-m antenna with South American coverage are presented to show the potential of the proposed antenna for spaceborne antennas in Ku-band.

Design of ultrawideband multilayer slot-coupled vertical microstrip transitions employing novel patch shapes

Design of two different slot-coupled vertical microstrip–microstrip transitions for ultrawideband (UWB) multilayer microwave circuits are introduced. Transitions consist of two stacked substrates with common ground in the middle and two microstrip-feed-lines connected to microstrip patches on the top and bottom. The proposed transitions use broadside coupling between microstrip patches at the top and the bottom layers via a rectangular-shaped slot in the common ground plane (midlayer). The proposed patch shapes are trapezoidal and butterfly shapes, which are capable of achieving broadband characteristics for UWB operation. Extensive parametric studies are performed to address the effect of varying the transition parameters on the coupling value and the operational frequency bandwidth. The simulated results using two simulation programs with two different numerical techniques show that the proposed transitions have low transmission coefficient (less than 1.2 dB) and a high reflection coefficient (better than 16 dB) over the 3.1–10.6 GHz frequency range. Two transition prototypes are fabricated and then tested experimentally using Agilent E8364B PNA Network Analyzer. Experimental results agree well with the simulated ones. © 2015 Wiley Periodicals, Inc. Microwave Opt Technol Lett 57:747–756, 2015

Micro Strip Patch Antenna Using Broadside Coupling

The prominent parameters of antenna are bandwidth and gain. For improving band width and gain there are many challenges for micro strip patch antenna. There are many designs for improving bandwidth and gain but there are some disadvantages of that design. The gain and bandwidth can be improved by using broadside coupling of patch. All designs are simulated with the help of HFSS software. Micro strip patch antenna used in mobile for communication purpose and also it is used in indoor and outdoor application for communication. DOI: 10.17762/ijritcc2321-8169.150108

BROADSIDE-COUPLED FILTERING CIRCULAR PATCH POWER DIVIDERS

Broadside coupling mechanism between difierent patch resonators is deployed for designing power dividers to provide bandpassing efiect. To demonstrate, two sector-shaped patches are combined and concentrically stacked on top of a circular microstrip resonator where pairs of concentric arc-shaped slots and radial notches are etched to perturb the current distribution so that an additional pole can be obtained to broaden the operational bandwidth. The use of circular patch enables the expansion of output ports without increasing the design complexity. Also, it was found that broadside coupling generates transmission zeros which can be used to sharpen the rollofi skirt for a better selectivity. In this paper, the corresponding design theory and methodology are elucidated, together with the detailed parametric analysis.

Dual‐mode dual‐band bandpass filters design using open‐loop slotline resonators

A dual-mode open-loop slotline resonator with a centre-loaded stub is proposed. The loaded stub is used to excite non-degenerate modes, that is, the even and odd modes. Distinct characteristics of this dual-mode resonator are investigated by using even–odd mode analysis. Also, equivalent circuit models for non-degenerate modes are given to determine the resonance conditions and the location of transmission zero. Then, two novel approaches for designing dual-mode dual-band bandpass filters are presented. One approach consists of simple microstrip feedlines and two embedded open-loop slotline resonators for single substrate configuration. The other is composed by using dual-mode open-loop resonators in the form of microstrip and slotline structures on a single substrate. A microstrip invert L-shape feeding structure is employed to simultaneously feed the microstrip and slotline resonator on different layers for broadside coupling. Both of them provide sufficient degrees of freedom to control the centre frequencies and fractional bandwidths of both passbands independently. The two filters are designed, fabricated and measured. A good agreement between the simulation and measurement verifies the validity of this design methodology.

A Wide-Stopband Bandpass Filter Using &lt; λ /16 Capacitive-Coupled Short-Circuited Resonators in Wide-Gap Coplanar Waveguide Structure

A compact bandpass filter (BPF) using a very short capacitively coupled resonator exhibits wide-stopband characteristics. It is based on two <λ/16 short-circuited resonators built on a coplanar waveguide (CPW) having unusually wide gap. The filter's input/output ports are connected to the resonator through microstrip-to-CPW broadside-coupled transition structure. The proposed filter is simple and compact without employing any additional structural elements that are often used in conventional approaches. It is found that the stopband characteristic can be significantly extended only by properly setting the coupling capacitance of the broadside coupling structure, the length of the resonator, and the CPW gap. A second-order BPF with a center frequency (f0) of 2.45 GHz and a 3-dB bandwidth of 10.6% is fabricated on a liquid crystal polymer substrate, demonstrating dramatically extended stopband suppression of 30 dB up to 9.8f0. © 2013 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:1752–1755, 2013

상용 65 n CMOS 공정을 이용한 100~110 GHz 저잡음 증폭기와 커플러

본 논문에서는 상용 65 n CMOS 공정을 이용하여 100~110 GHz에서 동작하는 저잡음 증폭기와 커플러를 구현하였다. 제작된 LNA는 3단 공통 소스 FET로 구성되었다. 단위 공통 소스 셀의 높은 이득 특성을 얻기 위해 이를 고려한 레이아웃을 하였다. 또한, 저잡음 특성과 충분한 이득을 얻기 위해 성능을 최적화시켰다. 커플러는 CMOS 공정의 multimetal을 이용한 broadside 커플러로 구성하였다. Density rule을 만족시키기 위한 metal strip을 사용해 이에 의한 영향을 고려해 커플러 동작이 가능하도록 설계하였다. 제작된 저잡음 증폭기의 측정 결과, 100 GHz에서 5.64 dB, 110 GHz에서 6.39 dB의 이득과 10 % 이상의 3-dB 대역폭, 11.66 dB의 잡음 지수를 얻었다. 커플러는 100~110 GHz 대역에서 2~3 dB의 삽입 손실, 1 dB 이하의 magnitude mismatch와 <TEX>$5^{\circ}$</TEX> 이하의 phase mismatch를 얻었다. In this paper, a 100~110 GHz LNA and A coupler using standard 65 n CMOS process is presented. The LNA consists of three common source FET stages. A few layout types are considered to get high gain characteristic of unit common source cell. Also, optimized performance to achieve low noise characteristic and enough gain. Coupler is composed of broadside coupler using multimetal in CMOS fabrication. In the coupler, the metal strip to meet density rule is used, and the coupler is designed with consideration of the metal strip to function properly. Gain of fabricated LNA is 5.64 dB at 100 GHz and 6.39 dB at 110 GHz. Bandwidth is over 10 % and noise figure is 11.66 dB at 100 GHz. Fabricated coupler has shown insertion loss of 2~3 dB at 100~110 GHz band. Magnitude mismatch of coupler is below 1 dB and phase mismatch of coupler is below <TEX>$5^{\circ}$</TEX>.