Bayesian adaptive randomization has attracted increasingly attention in the literature and has been implemented in many phase II clinical trials. Doubly adaptive biased coin design(DBCD) is a superior choice in respon...Bayesian adaptive randomization has attracted increasingly attention in the literature and has been implemented in many phase II clinical trials. Doubly adaptive biased coin design(DBCD) is a superior choice in response-adaptive designs owing to its promising properties. In this paper, we propose a randomized design by combining Bayesian adaptive randomization with doubly adaptive biased coin design. By selecting a fixed tuning parameter, the proposed randomization procedure can target an explicit allocation proportion, and assign more patients to the better treatment simultaneously. Moreover, the proposed randomization is efficient to detect treatment differences. We illustrate the proposed design by its applications to both discrete and continuous responses, and evaluate its operating features through simulation studies.展开更多
Based on the Gummel-Poon model of BJT, the change of the DC bias as a function of the AC input signal in RF linear power amplifiers is theoretically derived, so that the linearity of different DC bias circuits can be ...Based on the Gummel-Poon model of BJT, the change of the DC bias as a function of the AC input signal in RF linear power amplifiers is theoretically derived, so that the linearity of different DC bias circuits can be interpreted and compared. According to the analysis results, a quantitative adaptive DC bias circuit is proposed, which can improve the linearity and efficiency. From the simulation and test results, we draw conclusions on how to improve the design of linear power amplifier.展开更多
A novel broadband power amplifier fabricated in 0.13 m SiGe HBT technology is realized.The pseudo-differential structure is proposed to avoid the influence of the bonding wire due to the AC virtual ground created at t...A novel broadband power amplifier fabricated in 0.13 m SiGe HBT technology is realized.The pseudo-differential structure is proposed to avoid the influence of the bonding wire due to the AC virtual ground created at the common emitter node.A compensated matching technique is adopted in interstage matching to expand bandwidth.A multi-stage broadband matching technique is used in an input/output matching network to offer broadband impedance matching,which ensures maximum power transfer.An adaptive bias circuit could improve linearity and efficiency in wide output power level.With 2.5 V power supply,the measured results achieve 96% 3-dB bandwidth（517-1470 MHz）,27.2 dB power gain,26.9 dBm maximum output power,19.7 dBm output 1 dB compression point,and 26.7% power added efficiency.展开更多
A three-stage power amplifier （PA） for WLAN application in 2.4-2.5 GHz is presented. The proposed PA employs an adaptive bias circuit to adjust the operating point of the PA to improve the linearity of the PA. Two m...A three-stage power amplifier （PA） for WLAN application in 2.4-2.5 GHz is presented. The proposed PA employs an adaptive bias circuit to adjust the operating point of the PA to improve the linearity of the PA. Two methods to short the 2nd harmonic circuit are compared in the area of efficiency and gain of the PA. The PA is taped out in the process of 2/zm InGaP/GaAs HBT and is tested by the evaluation board. The measured results show that 31.5 dB power gain and 29.3 dBm PldB with an associated 40.4% power added efficiency （PAE） under the single tone stimulus. Up to 26.5 dBm output power can be achieved with an error vector magnitude （EVM） of lower than 3% under the 64QAM/OFDM WLAN stimulus.展开更多
基金Supported by a grant from The Research Grants Council of Hong Kong HKU7181/02H.The authors wishes to thank the referees for the constructive comments
基金supported by National Natural Science Foundation of China (Grant No. 11371366)Doctoral Research Fund of Henan Polytechnic University (Grant No. 672103/001/147)
文摘Bayesian adaptive randomization has attracted increasingly attention in the literature and has been implemented in many phase II clinical trials. Doubly adaptive biased coin design(DBCD) is a superior choice in response-adaptive designs owing to its promising properties. In this paper, we propose a randomized design by combining Bayesian adaptive randomization with doubly adaptive biased coin design. By selecting a fixed tuning parameter, the proposed randomization procedure can target an explicit allocation proportion, and assign more patients to the better treatment simultaneously. Moreover, the proposed randomization is efficient to detect treatment differences. We illustrate the proposed design by its applications to both discrete and continuous responses, and evaluate its operating features through simulation studies.
文摘Based on the Gummel-Poon model of BJT, the change of the DC bias as a function of the AC input signal in RF linear power amplifiers is theoretically derived, so that the linearity of different DC bias circuits can be interpreted and compared. According to the analysis results, a quantitative adaptive DC bias circuit is proposed, which can improve the linearity and efficiency. From the simulation and test results, we draw conclusions on how to improve the design of linear power amplifier.
文摘A novel broadband power amplifier fabricated in 0.13 m SiGe HBT technology is realized.The pseudo-differential structure is proposed to avoid the influence of the bonding wire due to the AC virtual ground created at the common emitter node.A compensated matching technique is adopted in interstage matching to expand bandwidth.A multi-stage broadband matching technique is used in an input/output matching network to offer broadband impedance matching,which ensures maximum power transfer.An adaptive bias circuit could improve linearity and efficiency in wide output power level.With 2.5 V power supply,the measured results achieve 96% 3-dB bandwidth（517-1470 MHz）,27.2 dB power gain,26.9 dBm maximum output power,19.7 dBm output 1 dB compression point,and 26.7% power added efficiency.
基金supported by the National Natural Science Foundation of China(No.61201244)the Natural Science Fund of SUES(No.E1-0501-14-0168)
文摘A three-stage power amplifier （PA） for WLAN application in 2.4-2.5 GHz is presented. The proposed PA employs an adaptive bias circuit to adjust the operating point of the PA to improve the linearity of the PA. Two methods to short the 2nd harmonic circuit are compared in the area of efficiency and gain of the PA. The PA is taped out in the process of 2/zm InGaP/GaAs HBT and is tested by the evaluation board. The measured results show that 31.5 dB power gain and 29.3 dBm PldB with an associated 40.4% power added efficiency （PAE） under the single tone stimulus. Up to 26.5 dBm output power can be achieved with an error vector magnitude （EVM） of lower than 3% under the 64QAM/OFDM WLAN stimulus.
