scholarly journals Frequency Tunable Non-Reciprocal Bandpass Filter and Diplexer Using Time-Modulated Microstrip λg/2 Resonators

2020 ◽  
Author(s):  
Xiaohu Wu ◽  
Mahmoud Nafe ◽  
Alejandro Alvarez Melcon ◽  
Juan Sebastian Gomez-Diaz ◽  
Xiaoguang Liu
Keyword(s):  
Insertion Loss ◽  
Bandpass Filter ◽  
Frequency Tuning ◽  
Wide Frequency Range ◽  
Voltage Source ◽  
Resonator Structure ◽  
Frequency Tunable ◽  
Rf Signal ◽  
Modulation Voltage ◽  
Good Agreement

This paper presents novel designs of frequency reconfigurable distributed non-reciprocal bandpass filter and diplexer based on spatio-temporally modulated microstrip λg/2 resonators. The modulation is achieved by loading both ends of the λg/2 transmission line resonators with time-modulated capacitors. To provide an inherent biasing isolation between the RF and the modulation signals, the modulation voltage source is connected at the center of the resonator, where there is a natural voltage null. A single inductor is used to further enhance such biasing isolation. The wideband nature of this isolation scheme enables the tuning of the devices over a wide frequency range. With more than 30-dB RF to modulation isolation, the proposed resonator structure also enables low insertion loss by eliminating RF signal leakage to the modulation ports. Two examples of a 3-pole bandpass filter and a diplexer are demonstrated with good agreement between the measurement and the simulation. The fabricated filter shows a minimal insertion loss of 3.9 dB, a 20-dB isolation bandwidth of 42 MHz at 1.0 GHz, and frequency tuning range of 885-1031 MHz. The measured diplexer has two non-reciprocal bandpass channels at 829 MHz and 997 MHz, respectively. The two channels can be independently reconfigured without affecting each other.

scholarly journals Frequency Tunable Non-Reciprocal Bandpass Filter and Diplexer Using Time-Modulated Microstrip λg/2 Resonators

2020 ◽  
Author(s):  
Xiaohu Wu ◽  
Mahmoud Nafe ◽  
Alejandro Alvarez Melcon ◽  
Juan Sebastian Gomez-Diaz ◽  
Xiaoguang Liu
Keyword(s):  
Insertion Loss ◽  
Bandpass Filter ◽  
Frequency Tuning ◽  
Wide Frequency Range ◽  
Voltage Source ◽  
Resonator Structure ◽  
Frequency Tunable ◽  
Rf Signal ◽  
Modulation Voltage ◽  
Good Agreement

This paper presents novel designs of frequency reconfigurable distributed non-reciprocal bandpass filter and diplexer based on spatio-temporally modulated microstrip λg/2 resonators. The modulation is achieved by loading both ends of the λg/2 transmission line resonators with time-modulated capacitors. To provide an inherent biasing isolation between the RF and the modulation signals, the modulation voltage source is connected at the center of the resonator, where there is a natural voltage null. A single inductor is used to further enhance such biasing isolation. The wideband nature of this isolation scheme enables the tuning of the devices over a wide frequency range. With more than 30-dB RF to modulation isolation, the proposed resonator structure also enables low insertion loss by eliminating RF signal leakage to the modulation ports. Two examples of a 3-pole bandpass filter and a diplexer are demonstrated with good agreement between the measurement and the simulation. The fabricated filter shows a minimal insertion loss of 3.9 dB, a 20-dB isolation bandwidth of 42 MHz at 1.0 GHz, and frequency tuning range of 885-1031 MHz. The measured diplexer has two non-reciprocal bandpass channels at 829 MHz and 997 MHz, respectively. The two channels can be independently reconfigured without affecting each other.

Design of multi-layered bandpass filter with independently controllable triple-passband response

2014 ◽  
Vol 6 (6) ◽  
pp. 611-618 ◽  
Author(s):  
Yung-Wei Chen ◽  
Hung-Wei Wu ◽  
Yan-Kuin Su
Keyword(s):  
Frequency Response ◽  
Bandpass Filter ◽  
Bottom Layer ◽  
Wide Frequency Range ◽  
Electromagnetic Simulation ◽  
Frequency Range ◽  
High Isolation ◽  
Full Wave ◽  
Simulation Results ◽  
Good Agreement

In this paper, a new multi-layered triple-passband bandpass filter using embedded and stub-loaded stepped impedance resonators (SIRs) is proposed. The filter is designed to have triple-passband at 1.8, 2.4, and 3.5 GHz. The 1st and 2nd passbands (1.8/2.4 GHz) are simultaneously generated by controlling the impedance and length ratios of the embedded SIRs (on top layer). The 3rd passband (3.5 GHz) is generated by using the stub-loaded SIR (on bottom layer). Using the embedded SIR, the even modes can be tuned within very wide frequency range and without affecting the odd modes. Therefore, the design of multi-band filters with very close passbands can be easily achieved and having a high isolation between the passbands. The filter can provide the multi-path propagation to enhance the frequency response and achieving the compact circuit size. The measured results are in good agreement with the full-wave electromagnetic simulation results.

scholarly journals Frequency-Tunable and Pattern Diversity Antennas for Cognitive Radio Applications

2014 ◽  
Vol 2014 ◽  
pp. 1-7 ◽  
Author(s):  
A. H. Ramadan ◽  
J. Costantine ◽  
Y. Tawk ◽  
C. G. Christodoulou ◽  
K. Y. Kabalan
Keyword(s):  
Cognitive Radio ◽  
Bandpass Filter ◽  
Microstrip Antennas ◽  
Open Loop ◽  
Tunable Filter ◽  
Radiation Characteristics ◽  
Wideband Antenna ◽  
Pattern Diversity ◽  
Frequency Tunable ◽  
Good Agreement

Frequency-tunable microstrip antennas, for cognitive radio applications, are proposed herein. The approach is based on tuning the operating frequency of a bandpass filter that is incorporated into a wideband antenna. The integration of an open loop resonator- (OLR-) based adjustable bandpass filter into a wideband antenna to transform it into a tunable filter-antenna is presented. The same technique is employed to design a cognitive radio pattern diversity tunable filter-antenna. A good agreement between the simulated and measured results for the fabricated prototypes is obtained. The radiation characteristics of each designed tunable filter-antenna are included herein.

scholarly journals Tuning the Resonance Frequency and Miniaturization of a Novel Microstrip Bandpass Filter

2018 ◽  
Vol 15 (2) ◽  
pp. 24
Author(s):  
Abbas Rezaei ◽  
Leila Noori
Keyword(s):  
Resonance Frequency ◽  
Design Process ◽  
Insertion Loss ◽  
Return Loss ◽  
Bandpass Filter ◽  
Design Method ◽  
Open Loop ◽  
Input Admittance ◽  
Low Insertion Loss ◽  
Good Agreement

In this paper, a compact microstrip bandpass filter is designed using two open loop resonators. In order to obtain a tunable bandpass response with low insertion loss, two stubs are loaded inside them. The design process is based on obtaining the input admittance. Then, using the input admittance, a method is presented to control the resonance frequency and miniaturization simultaneously. The obtained insertion loss and the return loss at the resonance frequency are 0.1 dB and 19.7 dB respectively. To verify the design method, the proposed filter is fabricated and measured. The measured results are in good agreement with the simulated results.

scholarly journals 60-GHz Half-Mode Substrate-Integrated Waveguide Bandpass Filter in 0.15-μm GaAs Technology

2021 ◽  
Vol 9 ◽  
Author(s):  
Xu-Juan Liu ◽  
Wen Wu ◽  
Kai-Da Xu ◽  
Ying-Jiang Guo ◽  
Qiang Chen
Keyword(s):  
Gallium Arsenide ◽  
Insertion Loss ◽  
Bandpass Filter ◽  
Center Frequency ◽  
Substrate Integrated Waveguide ◽  
60 Ghz ◽  
On Chip ◽  
Good Agreement

A compact 60-GHz on-chip bandpass filter (BPF) is presented using gallium arsenide (GaAs) technology. The miniaturization is achieved by the half-mode substrate-integrated waveguide (HMSIW) structure. Finally, a prototype of the BPF is fabricated and tested to validate the proposed idea, whose simulated and measured results are in good agreement. The measurements show that it has a center frequency at 58.6 GHz with a bandwidth of 17.9%, and the minimum insertion loss within the passband is 1.2 dB. The chip, excluding the feedings, is only about 0.38λg × 0.58λg, where λg is the guided wavelength at the center frequency.

scholarly journals Tuning the Resonance Frequency and Miniaturization of a Novel Microstrip Bandpass Filter

2018 ◽  
Vol 15 (2) ◽  
pp. 124
Author(s):  
Abbas Rezaei ◽  
Leila Noori
Keyword(s):  
Resonance Frequency ◽  
Design Process ◽  
Insertion Loss ◽  
Return Loss ◽  
Bandpass Filter ◽  
Design Method ◽  
Open Loop ◽  
Input Admittance ◽  
Low Insertion Loss ◽  
Good Agreement

In this paper, a compact microstrip bandpass filter is designed using two open loop resonators. In order to obtain a tunable bandpass response with low insertion loss, two stubs are loaded inside them. The design process is based on obtaining the input admittance. Then, using the input admittance, a method is presented to control the resonance frequency and miniaturization simultaneously. The obtained insertion loss and the return loss at the resonance frequency are 0.1 dB and 19.7 dB respectively. To verify the design method, the proposed filter is fabricated and measured. The measured results are in good agreement with the simulated results.

Frequency Tuning of a Nonlinear Electromagnetic Energy Harvester

2013 ◽  
Vol 136 (1) ◽  
Author(s):  
Longhan Xie ◽  
Ruxu Du
Keyword(s):  
Magnetic Field ◽  
Permanent Magnets ◽  
Energy Harvester ◽  
Frequency Tuning ◽  
Nonlinear Behavior ◽  
Stretch Ratio ◽  
Electromagnetic Energy ◽  
Elastic Strings ◽  
Simulation And Experiment ◽  
Frequency Tunable

This paper investigates a frequency-tunable nonlinear electromagnetic energy harvester. The electromagnetic harvester mainly consists of permanent magnets supported on the base to provide a magnetic field, and electrical coils suspended by four even-distributed elastic strings to be an oscillating object. When the base provides external excitation, the electrical coils oscillate in the magnetic field to produce electricity. The stretch length of the elastic strings can be tuned to change their stretch ratio by tuning adjustable screws, which can result in a shift of natural frequency of the harvester system. The transverse force of the elastic strings has nonlinear behavior, which broadens the system's frequency response to improve the performance of the energy harvester. Both simulation and experiment show that the above-discussed electromagnetic energy harvester has nonlinear behavior and frequency-tunable ability, which can be used to improve the effectiveness of energy harvesting.

Design of differential-mode bandpass filter with common-mode suppression using ring dielectric resonator

2016 ◽  
Vol 9 (5) ◽  
pp. 1029-1035 ◽  
Author(s):  
Jugul Kishor ◽  
Binod K. Kanaujia ◽  
Santanu Dwari ◽  
Ashwani Kumar
Keyword(s):  
Dielectric Resonator ◽  
High Performance ◽  
Bandpass Filter ◽  
Ring Resonator ◽  
Differential Mode ◽  
Common Mode ◽  
Mode Suppression ◽  
Transmission Zeros ◽  
System A ◽  
Good Agreement

Synthesis of differential-mode bandpass filter (BPF) with good common-mode suppression has been described and demonstrated on the basis of ring dielectric resonator (RDR) for high-performance communication system. A RDR with two pairs of feeding lines has been used to excite TE01δ-mode. This unique combination of feeding lines and the ring resonator creates a differential passband. Meanwhile, TM01δ-mode of the DR can also be excited to achieve common-mode rejection in the stopband. Transmission zeros are created in the lower and upper stopband to further improve the selectivity of the proposed BPF. A second-order differential BPF is designed, fabricated and its performance is measured to validate the concept. There is good agreement between simulated and measured results.

Adaptive Control of Pulse Width Modulation Voltage-Source Rectifier with Disturbance Signals

2013 ◽  
Vol 385-386 ◽  
pp. 977-980
Author(s):  
Bao Bin Liu
Keyword(s):  
Pulse Width ◽  
Pulse Width Modulation ◽  
Controller Design ◽  
Adaptive Controller ◽  
Voltage Source ◽  
Robust Controller ◽  
Reference Velocity ◽  
Velocity Tracking ◽  
Modulation Voltage ◽  
Robust Controller Design

A nonlinear adaptive controller is proposed for the design of pulse width modulation voltage-source rectifier with disturbance signals of harmonics to achieve reference velocity tracking. The procedure of the robust controller design is developed via improved backstepping method. With the proposed controller, PWM voltage-source rectifiers can guarantee accuracy of output voltage tracking. Global asymptotic stability of the closed-loop system has been proved. The simulation results demonstrate effectiveness of the presented method.

scholarly journals Using Waveguides to Model the Dynamic Stiffness of Pre-Compressed Natural Rubber Vibration Isolators

Polymers ◽  
2021 ◽  
Vol 13 (11) ◽  
pp. 1703
Author(s):  
Michael Coja ◽  
Leif Kari
Keyword(s):  
Natural Rubber ◽  
Dynamic Stiffness ◽  
Low Frequency ◽  
Complex Problem ◽  
Wide Frequency Range ◽  
Vibration Isolators ◽  
Standard Linear Solid ◽  
Standard Linear ◽  
Frequency Magnitude ◽  
Good Agreement

A waveguide model for a pre-compressed cylindrical natural rubber vibration isolator is developed within a wide frequency range—20 to 2000 Hz—and for a wide pre-compression domain—from vanishing to the maximum in service, that is 20%. The problems of simultaneously modeling the pre-compression and frequency dependence are solved by applying a transformation of the pre-compressed isolator into a globally equivalent linearized, homogeneous, and isotropic form, thereby reducing the original, mathematically arduous, and complex problem into a vastly simpler assignment while using a straightforward waveguide approach to satisfy the boundary conditions by mode-matching. A fractional standard linear solid is applied as the visco-elastic natural rubber model while using a Mittag–Leffler function as the stress relaxation function. The dynamic stiffness is found to depend strongly on the frequency and pre-compression. The former is resulting in resonance phenomena such as peaks and troughs, while the latter exhibits a low-frequency magnitude stiffness increase in addition to peak and trough shifts with increased pre-compressions. Good agreement with nonlinear finite element results is obtained for the considered frequency and pre-compression range in contrast to the results of standard waveguide approaches.

Sign in / Sign up

Export Citation Format

Share Document