Load‐modulation technique without using quarter‐wavelength transmission line

This paper presents new compact bandstop filters (BSFs) with extended upper passbands. In the basic proposed filter configuration, the conventional quarter-wavelength open-stub resonators are replaced with equivalent two-section stepped impedance resonators. Transmission line analysis is used to determine the dimensions of the equivalent stepped impedance sections. The filter structure is analyzed using a full wave electromagnetic (EM) simulator and then realized at 2.3 GHz band. Experiments have also been done to validate the performance of the design concept. Compared with the conventional quarter-wavelength-based bandstop filter, significant extensions of the upper passband beyond 9 GHz and 40% size reduction are achieved. Two other variations of the proposed basic BSF with further size reduction (more than 60%) are implemented and their measured performances are verified.

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High-Order Dual-Port Quasi-Absorptive Microstrip Coupled-Line Bandpass Filters

10.36227/techrxiv.12089268 ◽

2020 ◽

Author(s):

Xiaohu Wu ◽

Xiaoguang Liu ◽

Yingsong Li

Keyword(s):

Transmission Line ◽

Detailed Analysis ◽

Bandpass Filters ◽

Design Concept ◽

Coupled Line ◽

Input And Output ◽

Quarter Wavelength ◽

Measurement Results ◽

In Series ◽

Simultaneous Input

In this article, we present the first demonstration of distributed and symmetrical all-band quasi-absorptive filters that can be designed to arbitrarily high orders. The proposed quasi-absorptive filter consists of a bandpass section (reflective-type coupled-line filter) and absorptive sections (a matched resistor in series with a shorted quarter-wavelength transmission line). Through a detailed analysis, we show that the absorptive sections not only eliminate out-of-band reflections but also determine the passband bandwidth (BW). As such, the bandpass section mainly determines the out-of-band roll-off and the order of the filter can be arbitrarily increased without affecting the filter BW by cascading more bandpass sections. A set of 2.45-GHz one-, two-, and three-pole quasi-absorptive microstrip bandpass filters are designed and measured. The filters show simultaneous input and output absorption across both the passband and the stopband. Measurement results agree very well with the simulation and validate the proposed design concept.

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Load-Modulation Technique for Next Generation Mobile

2019 IEEE 2nd 5G World Forum (5GWF) ◽

10.1109/5gwf.2019.8911689 ◽

2019 ◽

Cited By ~ 1

Author(s):

Ahmed M. Abdulkhaleq ◽

Maan A. Yahya ◽

Jack Brunning ◽

Yasir Al-Yasir ◽

Naser O. Parchin ◽

...

Keyword(s):

Next Generation ◽

Modulation Technique ◽

Load Modulation

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Extended composite right/left-handed (E-CRLH) metamaterial and its application as quadband quarter-wavelength transmission line

2006 Asia-Pacific Microwave Conference ◽

10.1109/apmc.2006.4429669 ◽

2006 ◽

Cited By ~ 31

Author(s):

A. Rennings ◽

S. Otto ◽

J. Mosig ◽

C. Caloz ◽

I. Wolff

Keyword(s):

Transmission Line ◽

Left Handed ◽

Quarter Wavelength

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Wideband Microstrip 90° Hybrid Coupler Using High Pass Network

International Journal of Microwave Science and Technology ◽

10.1155/2014/854346 ◽

2014 ◽

Vol 2014 ◽

pp. 1-6 ◽

Cited By ~ 1

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.

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