scholarly journals Wideband Microstrip 90° Hybrid Coupler Using High Pass Network

2014 ◽  
Vol 2014 ◽  
pp. 1-6 ◽  
Author(s):  
Leung Chiu
Keyword(s):  
Transmission Line ◽  
Impedance Bandwidth ◽  
Phase Inverter ◽  
Branch Line ◽  
Quarter Wavelength ◽  
Lumped Elements ◽  
Hybrid Coupler ◽  
High Pass ◽  
Microstrip Circuit

A wideband 90° hybrid coupler has been presented and implemented in planar microstrip circuit. With similar structure of conversional 2-section branch-line coupler, the proposed coupler consists of a lumped high-pass network but not the quarter wavelength transmission at the center. The values of all lumped elements were optimized to replace a quarter-wavelength transmission line with a phase inverter. To demonstrate the proposed concept, a 1-GHz prototype was fabricated and tested. It achieves 90% impedance bandwidth with magnitude of S11 less than −10 dB. Within this bandwidth, more than 13 dB port-to-port isolation, less than 5.0 degree phase imbalance, and less than 4.5 dB magnitude imbalance are achieved, simultaneously. The proposed coupler not only achieves much wider bandwidth but also occupies less circuit area than that of the conversional 2-section branch-line coupler.

scholarly journals Compact and Wideband Parallel-Strip 180° Hybrid Coupler with Arbitrary Power Division Ratios

2013 ◽  
Vol 2013 ◽  
pp. 1-10 ◽  
Author(s):  
Leung Chiu ◽  
Quan Xue
Keyword(s):  
Characteristic Impedance ◽  
Impedance Bandwidth ◽  
Strip Line ◽  
Simple Design ◽  
Phase Inverter ◽  
Arbitrary Power ◽  
Absolute Phase ◽  
Parallel Strip ◽  
Hybrid Coupler ◽  
Good Agreement

This paper presents a class of wideband 180° hybrid (rat race) couplers implemented by parallel-strip line. By replacing the 270° arm of a conventional 180° hybrid coupler by a 90° arm with phase inverter, the bandwidth of the coupler is greatly enhanced and the total circuit size is reduced by almost half. Simple design formulas relating the characteristic impedance of the arms and power division ration are derived. To demonstrate the concept, four couplers with different power division ratios of 1, 2, 4, and 8 were designed, fabricated, and tested. S-parameters of the coupler are simulated and measured with good agreement. All working prototypes operate more than 112% impedance bandwidth with more than 25 dB port-to-port isolation and less than 5° absolute phase imbalance. The proposed 180° hybrid couplers can be employed as a wideband in-phase/differential power divider/combiner, which are essential for many RF and microwave subsystem designs.

Highly compact wideband double-section rat-race hybrid with harmonic suppression using series and shunt stepped impedance transmission lines

2016 ◽  
Vol 9 (4) ◽  
pp. 797-803 ◽  
Author(s):  
Kanaparthi V. Phani Kumar ◽  
S. S. Karthikeyan
Keyword(s):  
Transmission Line ◽  
Transmission Lines ◽  
Communication Systems ◽  
Printed Circuit Board ◽  
Circuit Board ◽  
Harmonic Suppression ◽  
Quarter Wavelength ◽  
Bonding Wires ◽  
Via Holes ◽  
Lumped Elements

This paper presents the design of a size miniaturized and harmonic suppressed wideband double-section rat-race coupler (RRC). Series and shunt stepped-impedance transmission line units are proposed to replace the quarter wavelength transmission lines in the conventional design of wideband (50% fractional bandwidth) two-stage rat-race coupler. Design equations are derived using the lossless transmission line model. The proposed double-section RRC occupies only 14% area of the conventional coupler, with good return loss and isolation performances. In addition, the full-wave simulation and measured responses exhibit harmonic suppression up to at least fifth harmonic. The proposed design can be easily implemented using the standard printed circuit board etching process without any via-holes, bonding wires, and lumped elements, which make it very useful for wireless communication systems

scholarly journals A Fully-Printed CRLH Dual-Band Dipole Antenna Fed by a Compact CRLH Dual-Band Balun

Sensors ◽  
2020 ◽  
Vol 20 (17) ◽  
pp. 4991
Author(s):  
Muhammad Kamran Khattak ◽  
Changhyeong Lee ◽  
Heejun Park ◽  
Sungtek Kahng
Keyword(s):  
Transmission Line ◽  
Mobile Applications ◽  
Phase Shifter ◽  
Design Method ◽  
Dipole Antenna ◽  
Dual Band ◽  
Dispersion Diagram ◽  
Left Handed ◽  
Lumped Elements ◽  
Hybrid Coupler

In this paper, a new design method is proposed for a planar and compact dual-band dipole antenna. The dipole antenna has arms as a hybrid CRLH (Composite right- and left-handed) transmission-line comprising distributed and lumped elements for the dual-band function. The two arms are fed by the outputs of a compact and printed CRLH dual-band balun which consists of a CRLH hybrid coupler and an additional CRLH phase-shifter. Its operational frequencies are 2.4 and 5.2 GHz as popular mobile applications. Verifying the method, the circuit approach, EM (Electromagnetics) simulation and measurement are conducted and their results turn out to agree well with each other. Additionally, the CRLH property is shown with the dispersion diagram and the effective size-reduction is mentioned.

Novel rat-race coupler design of arbitrary coupling coefficient using substrate integrated waveguide cavity

2018 ◽  
Vol 10 (8) ◽  
pp. 861-869 ◽  
Author(s):  
Min-Hua Ho ◽  
Yi-Hao Hong ◽  
Jen-Chih Li
Keyword(s):  
Transmission Lines ◽  
Coupling Coefficient ◽  
Substrate Integrated Waveguide ◽  
Cavity Field ◽  
Arbitrary Coupling ◽  
Degenerate Mode ◽  
Quarter Wavelength ◽  
Small Phase ◽  
Hybrid Coupler ◽  
Degenerate Modes

AbstractThe contribution of this paper is to propose a novel rat-race hybrid coupler of arbitrary coupling coefficient. Traditionally, the rat-race hybrid couplers are built by various loop-alike transmission-lines of multiple quarter-wavelength, and in this paper, we approach the coupler design by using a circular substrate integrated waveguide (SIW) cavity (SIWC). The employed SIWC supports two mutually orthogonal degenerate modes, and cavity field is formed by the two modes in an arbitrary weighting ratio which defines the proposed rat-race coupler's coupling coefficient. The cavity is excited by a microstrip combined coupling slot with the microstrip along a specifically chosen direction. The energy of each degenerate mode can be solely extracted by an associated subminiature version A (SMA) whose position is carefully determined. The isolation between the coupling slots is assured by their perpendicular layout, and the isolation between the SMA probes is obtained by the orthogonality of the two degenerate modes. Experiments are conducted on the 3- and 10-dB coupling coefficient samples to verify this novel rat-race coupler design. The measurements agree well with the simulations, and circuit's good performance is observed in terms of coupling precision, isolations, and small phase imbalances.

A Differential UWB Quasi-Yagi Antenna with A Reconfigurable Notched Band

Frequenz ◽  
2018 ◽  
Vol 72 (9-10) ◽  
pp. 401-406 ◽  
Author(s):  
Feng Wei ◽  
Xin Tong Zou ◽  
Xin Yi Wang ◽  
Bin Li ◽  
Xi Bei Zhao
Keyword(s):  
Microstrip Line ◽  
Design Procedure ◽  
Wide Band ◽  
Impedance Bandwidth ◽  
Differential Mode ◽  
Transition Structure ◽  
Notched Band ◽  
Quarter Wavelength ◽  
Yagi Antenna ◽  
Good Agreement

Abstract A compact differential ultra-wide band (UWB) planar quasi-Yagi antenna is presented in this paper. The proposed antenna consists of a balanced stepped-impedance microstrip-slotline transition structure, a driver dipole and one parasitic strip. A wide differential-mode (DM) impedance bandwidth covering from 3.8 to 9.5 GHz is realized. Meanwhile, a high and wideband common-mode (CM) suppression can be achieved by employing the balanced stepped-impedance microstrip-slotline transition structure. It is noted that the DM passband is independent from the CM response, which can significantly simplify the design procedure. In addition, a reconfigurable sharp DM notched band from 5.6 to 6.7 GHz is generated by adding one pair of quarter-wavelength varactor-loaded short-circuited stubs adjacent to the microstrip line symmetrically. In order to illustrate the effectiveness of the design, two prototypes of the antennas are designed, fabricated, and measured. A good agreement between the simulated and measured results is observed.

Sign in / Sign up

Export Citation Format

Share Document