2.0～3.5 GHz单路宽带低噪声放大器

使用微波仿真软件ADS设计了一款用于2.0³.5 GHz无线通信的宽带低噪声放大器。匹配网络采用微带线,减小了分立元件的寄生效应。详细阐述了提高放大器稳定性的方法,实现了PHEMT放大器在全频段的稳定性,并分析了源极反馈电感对放大器性能的影响。在2.03.5 GHz无线通信的宽带低噪声放大器。匹配网络采用微带线,减小了分立元件的寄生效应。详细阐述了提高放大器稳定性的方法,实现了PHEMT放大器在全频段的稳定性,并分析了源极反馈电感对放大器性能的影响。在2.0³.5 GHz频段内,放大器增益为12 dB左右,增益平坦度为0.23 dB,最大噪声系数为2.8 dB,输入输出驻波比小于2,三阶输出截点值OIP3大于35.5 dBm。设计的放大器可以用于无线通信的前段中。     

Multiband High-Linearity Front-end Receivers for Wireless Applications

In this paper, a modified front-end receiver configuration, which consists of an LNA and mixer suitable for zero-IF or low-IF receivers, is presented. The idea is to achieve a better linearity for receivers by combining circuit and system level solutions. Three circuit topologies, two in bipolar and one in CMOS technology, are presented in this paper with their simulation results. One of the bipolar topologies has been implemented and measurement results are presented. An IIP₃ of up to +0.6 dBm of a combined bipolar LNA and mixer is achieved, depending on frequency of interest and with an acceptable noise figure performance at a current consumption of less than 13 mA from 5 V supply voltage in one circuit and 3 V supply voltage in the other one. An IIP₃ up to +5 dBm is achieved for the CMOS topology at a lower overall gain and acceptable noise figure (14.4 mA and 3 V). All circuits presented in this paper are wideband circuits, suitable for area-efficient multiband receivers.     

一种高增益低功耗CMOS LNA设计

采用TSMC0.18μmCMOS工艺,利用ADS2008软件仿真,设计了一种高增益的CMOS低噪声放大器。与传统的共源共栅结构相比,该电路在晶体管M3的栅源极处并入电容C1,以增加系统抗干扰能力;并在级间引入一并联电感和电容与寄生电容谐振,以提高增益。仿真结果表明,在2.4 GHz工作频率下,该电路的增益大于20 dB,噪声系数小于1 dB,工作电压为1.5 V,功耗小于5 mW,且输入输出阻抗匹配良好。     

S波段低噪声放大器设计

首先分析了低噪声放大电路的稳定性,功率增益及噪声系数的影响因素及改进方法;然后设计了一个中心频率为2.45 GHz,工作带宽为100MHz的S波段低噪声放大器.仿真结果表明,该放大器的噪声系数小于1 dB,功率增益大于28 dB,增益平坦度小于1 dB,输入/输出驻波比小于2:1.通过传统的电路板制作工艺实际制作了放大器电路,测试结果和仿真结果较一致.     

废轮胎胶粉路面降噪应用研究

随着汽车工业的迅速发展,废轮胎对环境造成的压力越来越大,而交通噪声亦成为主要的噪声污染问题,利用废轮胎胶粉改性沥青铺设低噪路面,能解决上述两方面的环境问题,且能实现废弃物的资源化、无害化,这无疑具有极好的应用前景。就废轮胎胶粉在低噪路面的应用进行了综述,并就相关问题进行了展望。     

Bandwidth enhancement of the monopole antenna by using a parasitic normal-mode helix

An innovative monopole antenna coupled with a parasitic normal-mode helix has been designed and studied both experimentally and theoretically. The effects of various dimensions of the monopole and the parasitic helix were investigated extensively. This simple combination can significantly enhance the antenna bandwidth over that of the conventional monopole antenna. It is found that, with suitably chosen antenna dimensions, the VSWR bandwidth (VSWR ≤ 2) of the antenna can be increased to 36%, almost double that of the monopole antenna alone. The far-field pattern of the combined antenna is basically the same as that of the monopole antenna. This antenna is designed to operate at 1.8GHz. The substantially enhanced bandwidth of this simple and small antenna is a useful feature for future mobile communications.     

光伏型InSb红外探测器低噪声前放设计

以光伏型InSb红外探测器输出的微弱电流信号为依据对探测器的前置放大电路进行设计,并采用ORCAD电路仿真软件对所设计的低噪声、高增益放大电路的幅频响应、温度特性以及噪声进行了全面的分析和仿真。研究结果表明,该设计可以有效地提高信噪比和输出动态范围。     

基于最小噪声匹配的低噪放-天线一体化电路

传统的接收端天线与低噪声放大器(LNA)级联,通常需将天线输出阻抗与LNA的输入阻抗均匹配到50Ω,为此引入的匹配电路不仅占用了较大的电路尺寸,而且额外引入插入和失配等损耗。为消除匹配网络,本文提出一种基于ATF-54143晶体管的低噪放-天线一体化电路,基于最小噪声条件下将天线的阻抗与LNA晶体管的输入阻抗实现匹配。该方案通过直接优化微带天线的阻抗实现与LNA晶体管的宽带匹配,不使用任何形式的输入阻抗匹配网络来构建有源集成天线,从而克服了传统设计存在的问题和不足。实验测试表明,在2～3 GHz的带宽内,噪声系数(NF)较传统级联设计都有改善,且最大改善可达0.38 dB(较传统设计NF降低16%)。     

A 6-7 GHz, 40 dB receiver RF front-end with 4.5 dB minimum noise figure in 0.13μm CMOS for IR-UWB applications

A wideband receiver RP front-end for IR-UWB applications is implemented in 0.13μm CMOS technology. Thanks to the direct sub-sampling architecture,there is no mixing process.Both LNA and VGA work at RF frequencies.To optimize noise as well as linearity,a differential common-source LNA with capacitive cross- coupling is used,which only consumes current of 1.8 mA from a 1.2 V power supply.Following LNA,a two-stage current-steering VGA is adopted for gain tuning.To extend the overall bandwidth,a three-stage staggered peaking technique is used.Measurement results show that the proposed receiver front-end achieves a gain tuning range from 5 to 40 dB within 6-7 GHz,a minimum noise figure of 4.5 dB and a largest IIP₃ of-11 dBm.The core receiver （without test buffer） consumes 14 mW from a 1.2 V power supply and occupies 0.58 mm² area.     

宽频带低噪声放大器的设计

随着光纤通信、卫星通信向着宽频带方向发展,要求放大器的带宽也就越来越宽。文中设计了一种低噪声放大器,该放大器具有较低的噪声系数,同时工作频带较宽。增益平坦度在工作频段内控制在约1 dB,另外该低噪声放大器的输入输出匹配和稳定性良好。