小型化R波段限幅低噪声放大器设计

设计了一种小型化限幅低噪声放大器。采用Lange桥平衡结构,在实现低噪声的同时,得到较小的输入输出电压驻波比。采用集总参数和分布参数元件,实现了各级匹配。该小型化限幅低噪声放大器工作在R波段(2.1~2.5 GHz),噪声系数低于1 dB,输入输出驻波系数小于1.4,增益大于31 dB,带内增益波动只有±0.2 dB。通过SP2D开关实现两路输出,输出隔离度大于42 dB。     

小型化R波段限幅低噪声放大器设计

设计了一种小型化限幅低噪声放大器。采用Lange桥平衡结构,在实现低噪声的同时,得到较小的输入输出电压驻波比。采用集总参数和分布参数元件,实现了各级匹配。该小型化限幅低噪声放大器工作在R波段(2.1~2.5GHz),噪声系数低于1dB,输入输出驻波系数小于1.4,增益大于31dB,带内增益波动只有±0.2dB。通过SP2D开关实现两路输出,输出隔离度大于42dB。     

宽带限幅放大器的研制

从双极型晶体管Gummel-Poon模型出发,综合考虑晶体管的器件结构、工作状态和参数提取条件等完成参数提取,运用优化算法对提取参数进行局部和全局优化,给出了得到的GP模型参数值.以此为基础采用差分放大电路形式,完成限幅放大器电路结构设计并对其进行分析,运用ADS仿真软件对限幅放大器进行仿真优化并进行了流片.结果表明,设计完成的限幅放大器在10～300 MHz工作频率内的小信号电压增益最大值大于25 dB,带内平坦度小于±1 dB,限幅输出电压约为1.2 V.     

6-18GHz高增益宽带限幅放大器

本文介绍了一种具有高输出信噪比和温度补偿功能的高增益宽带限幅放大器的设计方法。该放大器由多片PHEMT工艺制作的单片集成电路构成，其主要特点是可在6～18GHz频率范围内、满足高输出信噪比的要求下实现对-60～-7dBm输入信号的限幅功能，并在-40～70℃的温度范围内提供稳定的增益输出，输出功率为13～17dBm，噪声系数小于4dB。     

2～18GHz微波宽带限幅放大器

采用 CAD技术 ,应用 Ga As HEMT管芯及良好的微组装工艺 ,研制出 2～ 1 8GHz微波宽带限幅放大器。基片为氧化铝材料 ,尺寸 0 .2 5 mm× 2 mm× 1 0 mm,自制超微带阻容元件 ,一并装在很小的铜载体上。经试验调试得到以下结果 :f:2～ 1 8GHz,Pout:3 0～ 5 0 m W,Gp≥ 60 d B,Fn≤ 5 d B,VSWR1≤ 2 .5 ,VSWR2≤ 2 .5。     

一种5.5 GHz 30-dB低成本CMOS宽带限幅放大器

采用0.18 μm CMOS工艺,设计了一种多级级联的差分架构宽带高增益限幅放大器.该限幅放大器是为5 Gb/s同步光纤网络(SONET OC-96)设计的.采用反比例级联结构和低电压降有源电感负载来提高系统带宽,达到了设计目标.仿真结果显示,该限幅放大器获得了约30 dB的增益和5.5 GHz 3 dB带宽,电路功耗为30 m W.     

低功耗CMOS限幅放大器设计

利用0.18μm CMOS工艺设计了应用于光接收机中的10Gb/s限幅放大器.此限幅放大器由输入缓冲,4级放大单元,一级用于驱动50Ω传输线的输出缓冲和失调电压补偿回路构成.输入动态范围为38dB(10mV～800mV),负载上的输出限幅在400mV,在3.3V电源电压下,功耗仅为99mW.整个芯片面积为0.8×1.3mm2.     

基于标准CMOS工艺的一款宽带限幅放大器芯片设计

采用SMIC 0．35μm CMOS混合信号工艺来设计开发一款适用于SDH STM-16的光接收机前端限幅放大器芯片。该限幅放大器的设计采用了电容中和技术来实现带宽的扩展,可满足2．5Gbps速率要求,芯片电路拥有信号丢失检测和自动静噪功能。芯片版图的参数提取仿真表明：芯片最小输入动态范围可达2mV,50Ω负载上的双端输出摆幅约为1400mVpp在3．3V供电下静态功耗仅为66mW,动态功耗为105mW,有实际推广价值。     

星载小型化宽带全向印制天线

针对星载无缆化通信的需求,研究了展宽印制天线工作带宽的方法。设计了星载小型化宽带全向印制天线,通过三维全波电磁仿真软件(CST)进行了仿真分析与优化设计。在此基础上加工了天线实物样件,并对其电性能进行了测试。仿真结果表明该天线具有小型化、宽带、全向等特点。     

Design tradeoffs for sub-mW CMOS biomedical limiting amplifiers

This paper presents design considerations on CMOS limiting amplifiers to be used as basic building blocks for power-efficient logarithmic amplifiers. The impact of mismatches and device-level properties on sensitivity and gain-bandwidth product is discussed. To this end, a comparison of several types of low-voltage gain cell topologies is presented. Based on statistical (Monte Carlo) results, a high-sensitivity eight-stage limiting amplifier tolerant of process spreads and devices mismatches was designed in 0.35 μm CMOS technology to operate over dc to 20 MHz bandwidth and experimentally evaluated. The proposed limiting amplifier draws 280 μA from a 2-V supply and achieves a voltage gain of 72 dB.     

一种紧凑的双极化超宽带MIMO天线设计

设计了一种紧凑的双极化超宽带MIMO天线。该天线由一个六边形的贴片组成,它具有结构紧凑、体积小的特点。在六边形的地板平面上接一个矩形垂直臂,实现了35%的3 dB轴比带宽以及两个端口之间的隔离。在矩形垂直臂中加入两个L型散热器,提高了隔离度,这种双极化的MIMO天线可以减少多径衰落的影响。测量结果表明:该天线在超宽带频带内保持良好的全向辐射特性,天线增益小于5 dBi,隔离比大于15 dB,包络相关系数(ECC)小于0.01,该天线可以应用于超宽带无线通信系统。     

Erbium-doped-fiber optical limiting amplifiers

A novel configuration of an erbium-doped-fiber optical output-limiting amplifier (OLA) is presented which is realized by simply introducing a differential lump-loss between the signal and the pump power at a particular point along the fiber. The OLA exhibits an input-power dynamic range in excess of 40 dB and the capacity to control optically the level of the constant-output signal     

Design of broadband microwave amplifiers with mixed-elements via reflectance data modeling

A practical method is introduced, to design single-stage broadband microwave amplifiers with mixed lumped and distributed elements via modeling the reflectance data obtained from lumped-element input and output matching network prototypes. The same transducer power gain level is obtained by using less number of lumped-elements in the mixed-element amplifier than that of the lumped-element amplifier prototype. A mixed-element amplifier design is presented, to exhibit the utilization of the method. It is expected that the method will be employed, to design microwave amplifiers for broadband communication systems.     

Synthesis of broadband microwave transistor amplifiers

The design of broadband microwave transistor amplifiers is discussed in terms of direct synthesis of distributed commensurate matching networks. Examples are given for both single-stage and 2-stage amplifiers, using ladder networks realisable in stripline form.     

Power combination of broadband TRAPATT amplifiers

The power from two closely matched trapatt amplifiers was combined by means of two 3dB interdigitated hybrid couplers. An output power of 115 W with 350 MHz bandwidth was obtained from the combined circuit. This combination technique, the effectiveness of which was thought to be questionable for trapatt amplifiers, doubles their output power without causing loss of bandwidth.     

Design of compact broadband TSA arrays by using element mutual coupling

A compact broadband tapered slot antenna (TSA) array was designed, which can achieve a bandwidth of 4.5?18 GHz with scan angle up to 608. Contrary to the conventional array design, the key to this design was taking advantage of mutual coupling between closely-spaced elements. A generic analytical-based method was developed to predict the mutual coupling between elements in the TSA array and the strong coupling between TSA elements was identified as being essential to the operation of arrays over broad bandwidth.     

Gain-enhanced compact broadband microstrip antenna

With the loading of a high-permittivity superstrate layer and a 1 Ω chip resistor, a compact rectangular microstrip antenna with enhanced gain and wider bandwidth can be implemented. With the antenna size reduced to be ~6% that of a conventional patch antenna, the proposed structure can have an operating bandwidth of more than six times that of a conventional patch antenna, with an almost equal antenna gain level. Details of the experimental results are presented and discussed