The Experts below are selected from a list of 46248 Experts worldwide ranked by ideXlab platform
Cam Nguyen - One of the best experts on this subject based on the ideXlab platform.
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a k text ka band concurrent dual band single ended input to Differential Output low noise amplifier employing a novel transformer feedback dual band load
IEEE Transactions on Circuits and Systems, 2018Co-Authors: Cam NguyenAbstract:A concurrent dual-band single-ended input to Differential Output (single-ended-to-Differential) low-noise amplifier (LNA) employing a novel transformer feedback single-ended-to-Differential dual-band load is proposed. The developed LNA topology is flexible in controlling the stopband notch frequency by optimizing the transformer’s self-inductance and coupling coefficient. It also has a unique advantage in controlling both the stopband rejection and passband gain balance, simultaneously. The LNA is designed using a 0.18- $\mu \text{m}$ BiCMOS process and exhibits the same single-ended-to-Differential peak gains of 19.2 dB at 21.5 and 36 GHz in the low- and high-passband, respectively, with the stopband rejection ratio of 37.1 dB. In the single-ended input to single-ended Output (single-ended) mode operation, the designed LNA exhibits the measured peak gains of 15.7/16.6 dB at 21.5 GHz and 15.7/16.7 dB at 36 GHz for the two signal paths. It achieves the best measured single-ended noise figures of 4.3/4.0 and 4.3/4.2 dB for the two signal paths in the respective low and high passbands. The LNA also attains the measured Differential gain and phase imbalances of 0.9/1.0 dB and 0.5/10.4 degree in the low/high passband, respectively. This LNA is the first concurrent dual-band single-ended-to-Differential LNA integrated on-chip operating in ${K}$ - and Ka -band.
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A $K\text{-}/Ka$ -Band Concurrent Dual-Band Single-Ended Input to Differential Output Low-Noise Amplifier Employing a Novel Transformer Feedback Dual-Band Load
IEEE Transactions on Circuits and Systems I: Regular Papers, 2018Co-Authors: Jaeyoung Lee, Cam NguyenAbstract:A concurrent dual-band single-ended input to Differential Output (single-ended-to-Differential) low-noise amplifier (LNA) employing a novel transformer feedback single-ended-to-Differential dual-band load is proposed. The developed LNA topology is flexible in controlling the stopband notch frequency by optimizing the transformer’s self-inductance and coupling coefficient. It also has a unique advantage in controlling both the stopband rejection and passband gain balance, simultaneously. The LNA is designed using a 0.18- $\mu \text{m}$ BiCMOS process and exhibits the same single-ended-to-Differential peak gains of 19.2 dB at 21.5 and 36 GHz in the low- and high-passband, respectively, with the stopband rejection ratio of 37.1 dB. In the single-ended input to single-ended Output (single-ended) mode operation, the designed LNA exhibits the measured peak gains of 15.7/16.6 dB at 21.5 GHz and 15.7/16.7 dB at 36 GHz for the two signal paths. It achieves the best measured single-ended noise figures of 4.3/4.0 and 4.3/4.2 dB for the two signal paths in the respective low and high passbands. The LNA also attains the measured Differential gain and phase imbalances of 0.9/1.0 dB and 0.5/10.4 degree in the low/high passband, respectively. This LNA is the first concurrent dual-band single-ended-to-Differential LNA integrated on-chip operating in ${K}$ - and Ka -band.
Guibin Zou - One of the best experts on this subject based on the ideXlab platform.
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Travelling wave pilot protection for LCC-HVDC transmission lines based on electronic transformers’ Differential Output characteristic
International Journal of Electrical Power & Energy Systems, 2017Co-Authors: Dong Wang, Houlei Gao, Sibei Luo, Guibin ZouAbstract:Abstract Considering travelling wave’s bandwidth which varies from several kilohertz to hundreds of kilohertz, traditional current and voltage transformers cannot transfer whole bandwidth of travelling wave. However, electronic transformers, including Rogowski coil based electronic current transformer and capacitance divided electronic voltage transformer, have much wider bandwidth (up to 500 kHz) which could transfer almost whole bandwidth of travelling wave without distortion. Besides, secondary side’s Output of electronic transformer is the Differential signal of primary side. So, the integration circuit can be omitted when using Differential travelling wave signal directly in protection principle. Traditional travelling protection for high voltage direct current (HVDC) lines is highly affected by grounding resistance. And the backup protection, such as current Differential protection, has long operation time. So the paper proposes a novel travelling wave pilot protection based on the Differential Output signal of electronic transformers. Differential voltage and current travelling wave have axisymmetric relationship when the fault occurs at forward direction. Conversely, Differential voltage and current travelling wave almost overlap when the fault occurs at reverse direction. Considering fault direction identification results of two ends, fault section can be determined. Besides, according to amplitude ratio of fault line and normal line, fault line can be selected correctly. The simulation results in PSCAD/EMTDC prove the correctness, sensitivity and reliability.
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Travelling wave fault location principle based on Rogowski coil's Differential Output and Hilbert-Huang transform
13th International Conference on Development in Power System Protection 2016 (DPSP), 2016Co-Authors: Dong Wang, Houlei Gao, Sibei Luo, Guibin ZouAbstract:Travelling wave fault location method has been used in power system, but its performance was affected by the frequency band limitation (
Jaeyoung Lee - One of the best experts on this subject based on the ideXlab platform.
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A $K\text{-}/Ka$ -Band Concurrent Dual-Band Single-Ended Input to Differential Output Low-Noise Amplifier Employing a Novel Transformer Feedback Dual-Band Load
IEEE Transactions on Circuits and Systems I: Regular Papers, 2018Co-Authors: Jaeyoung Lee, Cam NguyenAbstract:A concurrent dual-band single-ended input to Differential Output (single-ended-to-Differential) low-noise amplifier (LNA) employing a novel transformer feedback single-ended-to-Differential dual-band load is proposed. The developed LNA topology is flexible in controlling the stopband notch frequency by optimizing the transformer’s self-inductance and coupling coefficient. It also has a unique advantage in controlling both the stopband rejection and passband gain balance, simultaneously. The LNA is designed using a 0.18- $\mu \text{m}$ BiCMOS process and exhibits the same single-ended-to-Differential peak gains of 19.2 dB at 21.5 and 36 GHz in the low- and high-passband, respectively, with the stopband rejection ratio of 37.1 dB. In the single-ended input to single-ended Output (single-ended) mode operation, the designed LNA exhibits the measured peak gains of 15.7/16.6 dB at 21.5 GHz and 15.7/16.7 dB at 36 GHz for the two signal paths. It achieves the best measured single-ended noise figures of 4.3/4.0 and 4.3/4.2 dB for the two signal paths in the respective low and high passbands. The LNA also attains the measured Differential gain and phase imbalances of 0.9/1.0 dB and 0.5/10.4 degree in the low/high passband, respectively. This LNA is the first concurrent dual-band single-ended-to-Differential LNA integrated on-chip operating in ${K}$ - and Ka -band.
Dong Wang - One of the best experts on this subject based on the ideXlab platform.
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Travelling wave pilot protection for LCC-HVDC transmission lines based on electronic transformers’ Differential Output characteristic
International Journal of Electrical Power & Energy Systems, 2017Co-Authors: Dong Wang, Houlei Gao, Sibei Luo, Guibin ZouAbstract:Abstract Considering travelling wave’s bandwidth which varies from several kilohertz to hundreds of kilohertz, traditional current and voltage transformers cannot transfer whole bandwidth of travelling wave. However, electronic transformers, including Rogowski coil based electronic current transformer and capacitance divided electronic voltage transformer, have much wider bandwidth (up to 500 kHz) which could transfer almost whole bandwidth of travelling wave without distortion. Besides, secondary side’s Output of electronic transformer is the Differential signal of primary side. So, the integration circuit can be omitted when using Differential travelling wave signal directly in protection principle. Traditional travelling protection for high voltage direct current (HVDC) lines is highly affected by grounding resistance. And the backup protection, such as current Differential protection, has long operation time. So the paper proposes a novel travelling wave pilot protection based on the Differential Output signal of electronic transformers. Differential voltage and current travelling wave have axisymmetric relationship when the fault occurs at forward direction. Conversely, Differential voltage and current travelling wave almost overlap when the fault occurs at reverse direction. Considering fault direction identification results of two ends, fault section can be determined. Besides, according to amplitude ratio of fault line and normal line, fault line can be selected correctly. The simulation results in PSCAD/EMTDC prove the correctness, sensitivity and reliability.
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Travelling wave fault location principle based on Rogowski coil's Differential Output and Hilbert-Huang transform
13th International Conference on Development in Power System Protection 2016 (DPSP), 2016Co-Authors: Dong Wang, Houlei Gao, Sibei Luo, Guibin ZouAbstract:Travelling wave fault location method has been used in power system, but its performance was affected by the frequency band limitation (
Chi Hou Chan - One of the best experts on this subject based on the ideXlab platform.
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a wideband compact parallel strip 180 spl deg wilkinson power divider for push pull circuitries
IEEE Microwave and Wireless Components Letters, 2006Co-Authors: Leung Chiu, Chi Hou ChanAbstract:A Wilkinson power divider with a Differential Output implemented in parallel-strip-line (PSL) is proposed. Taking full advantages of the PSL technology and a three-stage cascaded design, more than 170% impedance and isolation bandwidths are obtained. Inherent to the PSL structure, the 180deg Differential Output is frequency-independent. A class-B push-pull power amplifier employing the devised concept is designed, showing a peak efficiency of 44% over a 4-GHz bandwidth. Without exploiting any extra and external low-pass filters, the proposed design can produce startling second-harmonic suppressions (more than 50dB) over the whole working dynamics and operated bandwidth
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A wideband compact parallel-strip 180/spl deg/ Wilkinson power divider for push-pull circuitries
IEEE Microwave and Wireless Components Letters, 2006Co-Authors: Leung Chiu, T.y. Yum, Quan Xue, Chi Hou ChanAbstract:A Wilkinson power divider with a Differential Output implemented in parallel-strip-line (PSL) is proposed. Taking full advantages of the PSL technology and a three-stage cascaded design, more than 170% impedance and isolation bandwidths are obtained. Inherent to the PSL structure, the 180deg Differential Output is frequency-independent. A class-B push-pull power amplifier employing the devised concept is designed, showing a peak efficiency of 44% over a 4-GHz bandwidth. Without exploiting any extra and external low-pass filters, the proposed design can produce startling second-harmonic suppressions (more than 50dB) over the whole working dynamics and operated bandwidth