Results 291 to 300 of about 3,627,033 (322)
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A Tunable Bandpass Filter with Constant Absolute Bandwidth
Journal of Electromagnetic Waves and Applications, 2011A novel tunable bandpass filter with constant absolute bandwidth is presented in this paper. Introducing a mixed electric and magnetic coupling structure and a new external coupling scheme, nearly constant absolute bandwidth is maintained across the tuning range. Theoretical analysis and design approach are demonstrated. The proposed filter is designed
B. Liu, F. Wei, Q. Y. Wu, X. W. Shi
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IEEE transactions on microwave theory and techniques, 2019
This article proposes an advanced synthesis of the frequency-adaptive bandpass filter (FA-BPF) with constant absolute bandwidth (ABW). The proposed synthesis is based on the element-variable coupling matrix (EVCM), which is directly extracted from the ...
Di Lu +5 more
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This article proposes an advanced synthesis of the frequency-adaptive bandpass filter (FA-BPF) with constant absolute bandwidth (ABW). The proposed synthesis is based on the element-variable coupling matrix (EVCM), which is directly extracted from the ...
Di Lu +5 more
semanticscholar +1 more source
Bandwidths of the Equal Time-Constant Amplifier
Nuclear Instruments and Methods, 1960S>Formulas are developed for the effective noise bandwidths for amplifiers with both upper and lower pass band limits defined by equal RC time constants. The half-power or 3db bandwidth is found to be twice the center frequency; whereas the effective noise bandwidth is found to be proportional to the shot noise in addition to being dependent on the ...
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Constant bandwidth voltage amplification using current conveyors
International Journal of Electronics, 1988Traditional feedback voltage amplifier formulations suffer from the restriction of a constant gain-bandwidth product, reducing the bandwidth dramatically at higher gains. A feedback voltage amplifier designed around a current conveyor or current amplifier completely overcomes this restriction and permits maximum bandwidth to be obtained for all values ...
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Ultra-Selective Constant-Bandwidth Electromechanically Tunable HTS Filters
2006 IEEE MTT-S International Microwave Symposium Digest, 2006We report an ultra narrow band 3-pole tunable filter. Tuning from 770 MHz up to 930 MHz, which is about 20%, was demonstrated. Insertion loss was 0.7 dB at 770 MHz and 1.6 dB at 930 MHz. Coupling bandwidth was kept almost constant over the entire range. A novel filter configuration and tuning algorithm is proposed and demonstrated.
Genichi Tsuzuki +4 more
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IEEE transactions on microwave theory and techniques, 2019
This paper presents a method for designing low-loss varactor-based tunable bandpass filters (BPFs) with constant absolute bandwidth (CABW) and wide tuning range based on coaxial resonators. The whole structure consists of a metallic cavity and a piece of
Jin-Xu Xu +3 more
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This paper presents a method for designing low-loss varactor-based tunable bandpass filters (BPFs) with constant absolute bandwidth (CABW) and wide tuning range based on coaxial resonators. The whole structure consists of a metallic cavity and a piece of
Jin-Xu Xu +3 more
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Wide bandwidth constant current source for ac galvanomagnetic measurements
Review of Scientific Instruments, 1979A simple one-op-amp constant current source which has great versatility is described. Its important features include a wide bandwidth (≳10 kHz) and the ability to float from third-wire ground. Applications to three separate types of measurement are included, ac conductivity measurements on ionic conductors, Double-ac Hall effect measurements, and ...
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Microstrip tunable bandstop filter with constant absolute bandwidth
Journal of Electromagnetic Waves and Applications, 2014This paper presents a novel designing approach for tunable bandstop filters (BSPs) with constant absolute bandwidth (CABW). A simple bandstop unit is introduced to design tunable BSPs. Through the analysis, the bandwidth and center frequency of the unit can be fully controlled.
Dinghong Jia +3 more
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IEEE transactions on microwave theory and techniques, 2018
This paper presents a novel configuration for a high-Q tunable waveguide (WG) filter with a constant absolute bandwidth (BW). The key feature of this filter is that it is tuned by a single tuning element.
Gowrish Basavarajappa, R. Mansour
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This paper presents a novel configuration for a high-Q tunable waveguide (WG) filter with a constant absolute bandwidth (BW). The key feature of this filter is that it is tuned by a single tuning element.
Gowrish Basavarajappa, R. Mansour
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Tunable suspended substrate stripline filters with constant bandwidth
2011 IEEE MTT-S International Microwave Symposium, 2011A suspended substrate tunable filter is presented. Meandered input and inter-resonator coupling structures are introduced to reduce bandwidth variation across the tuning range. Simulated and experimental results are presented to verify the validity of the proposed concept. A two-pole filter is fabricated and tested.
Nino Zahirovic +3 more
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