期刊文献+
共找到5篇文章
< 1 >
每页显示 20 50 100
Improved Interference Suppression Algorithm Against Broadband BPSK Interference 被引量:1
1
作者 安建平 夏彩杰 王爱华 《Journal of Beijing Institute of Technology》 EI CAS 2008年第2期212-216,共5页
An improved polar exciser (IMPE) interference suppression method against broadband constant envelope binary phase shift keying (BPSK) interference is proposed. The disadvantage of traditional polar exciser (PE) ... An improved polar exciser (IMPE) interference suppression method against broadband constant envelope binary phase shift keying (BPSK) interference is proposed. The disadvantage of traditional polar exciser (PE) is the performance degradation when the power of interference is low, i.e., the threshold effect. The proposed improved PE (IMPE) algorithm can overcome the threshold effect of PE by introducing compression gain (CG) metric, which forces PE suppressor active only at larger jammer-to-signal ratio (JSR) and switch to matched filter (MF) at lower JSR. Theoretical analysis and numerical simulations show the exactness of CG as a switching metric and the validity of the IMPE algorithm. 展开更多
关键词 polar exciser (PE) compression gain (CG) improved PE bit error rate
下载PDF
A monolithic InGaP/GaAs HBT power amplifier for W-CDMA applications 被引量:1
2
作者 黄继伟 王志功 +2 位作者 廖英豪 陈志坚 方志坚 《Journal of Southeast University(English Edition)》 EI CAS 2011年第2期132-135,共4页
A monolithic microwave integrated circuit (MMIC) power amplifier (PA) is proposed. It adopts a new on-chip bias circuit, which not only avoids the instability of the direct current bias caused by the change in the... A monolithic microwave integrated circuit (MMIC) power amplifier (PA) is proposed. It adopts a new on-chip bias circuit, which not only avoids the instability of the direct current bias caused by the change in the power supply and temperature, but also compensates deviations caused by the increase in input power. The bias circuit is a current-mirror configuration, and the feedback circuit helps to maintain bias voltage at a constant level. The gain of the feedback circuit is improved by the addition of a non-inverting amplifier within the feedback circuit. A shunt capacitor at the base node of the active bias transistor enhances the linearity of the PA. The chip is fabricated in an InGaP/GaAs heterojunction bipolar transistor (HBT) process. Measured results exhibit a 26. 6-dBm output compression point, 33.6% power-added efficiency (PAE) and - 40.2 dBc adjacent channel power ratio (ACPR) for wide-band code division multiple access (W-CDMA) applications. 展开更多
关键词 power amplifier wide-band code division multipleaccess(W-CDMA) heterojunction bipolar transistor (HBT) bias circuit gain compression
下载PDF
ISM Band Medium Power Amplifier 被引量:1
3
作者 白大夫 刘训春 +1 位作者 袁志鹏 钱永学 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2004年第6期626-632,共7页
With the large-signal model extracted from the InGaP/GaAs HBT with three fingers,a three-stage,class AB power amplifier at ISM band is designed.Through the optimization of the traditional bias network,the gain compres... With the large-signal model extracted from the InGaP/GaAs HBT with three fingers,a three-stage,class AB power amplifier at ISM band is designed.Through the optimization of the traditional bias network,the gain compression at the low input power level is eliminated successfully.At 3.5V of supply voltage of the power amplifier after optimization exhibits 30dBm of maximum linear output power,43.4% of power added efficiency 109.7mA of a quite low quiescent bias current ,29.1dB of the corresponding gain,and -100dBc of the adjacent channel power rejection (ACPR) at the output power of 30dBm. 展开更多
关键词 heterojunction bipolar transistor power amplifier bias network gain compression quiescent bias current
下载PDF
An X-band GaN combined solid-state power amplifier
4
作者 陈炽 郝跃 +4 位作者 冯辉 杨林安 马晓华 段焕涛 胡仕刚 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2009年第9期57-61,共5页
Based on a self-developed A1GaN/GaN HEMT with 2.5 mm gate width technology on a SiC substrate, an X-band GaN combined solid-state power amplifier module is fabricated. The module consists of an AIGaN/GaN HEMT, Wilkins... Based on a self-developed A1GaN/GaN HEMT with 2.5 mm gate width technology on a SiC substrate, an X-band GaN combined solid-state power amplifier module is fabricated. The module consists of an AIGaN/GaN HEMT, Wilkinson power couplers, DC-bias circuit and microstrip line. For each amplifier, we use a bipolar DC power source. Special RC networks at the input and output and a resistor between the DC power source and the gate of the transistor at the input are used for cancellation of self-oscillation and crosstalk of low-frequency of each amplifier. At the same time, branches of length 3λ/4 for Wilkinson power couplers are designed for the elimination of self-oscillation of the two amplifiers. Microstrip stub lines are used for input matching and output matching. Under Vds = 27 V, Vgs = -4.0 V, CW operating conditions at 8 GHz, the amplifier module exhibits a line gain of 5.6 dB with power added efficiency of 23.4%, and output power of 41.46 dBm (14 W), and the power gain compression is 3 dB. Between 8 and 8.5 GHz, the variation of output power is less than 1.5 dB. 展开更多
关键词 AlGaN/GaN HEMT solid-state power amplifiers output power gain compression power added efficiency
原文传递
High efficiency class-I audio power amplifier using a single adaptive supply
5
作者 彭振飞 杨姗姗 +2 位作者 冯勇 刘洋 洪志良 《Journal of Semiconductors》 EI CAS CSCD 2012年第9期95-101,共7页
A high efficiency class-1 linear audio power amplifier (PA) with an adaptive supply is presented. Its efficiency is improved by a dynamic supply to reduce the power transistors' voltage drop. A gain compression tec... A high efficiency class-1 linear audio power amplifier (PA) with an adaptive supply is presented. Its efficiency is improved by a dynamic supply to reduce the power transistors' voltage drop. A gain compression technique is adopted to make the amplifier accommodate a single positive supply. Circuit complicity and chip area are reduced because no charge pump is necessary for the negative supply. A common shared mode voltage and a symmetric layout pattern are used to minimize the non-linearity. A peak efficiency of 80% is reached at peak output power. The measured THD+N before and after the supply switching point are 0.01% and 0.05%, respectively. The maximum output power is 410 mW for an 8 f2 speaker load. Unlike switching amplifiers, the class-I amplifier operates as a linear amplifier and hence has a low EMI. The advantage of a high efficiency and low EMI makes the class-1 amplifier suitable for portable and RF sensitive applications. 展开更多
关键词 class-1 power amplifier gain compression adaptive supply power efficiency
原文传递
上一页 1 下一页 到第
使用帮助 返回顶部