共查询到15条相似文献,搜索用时 46 毫秒
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介绍了X波段极低噪声低温放大器的研制。在≤15K的环境温度下,X波段100MHz带宽内,实测放大器的等效噪声温度:≤8.8K;增益:>36dB;带内起伏:<0.4dB;输入反射损耗:<-22dB;输出反射损耗:<-20dB。它的研制成功,将可以替代进口产品满足X波段低温接收机的研制需要。 相似文献
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介绍了低温低噪声放大器使用的HEMT(高迁移率晶体管)器件噪声模型的建立,对HEMT用S参数和噪声参数讲行仿直,获取适合的模型.给出了实例,放大器在低温10K工作,增益≥30dB,噪声温度≤4K. 相似文献
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介绍了X波段低温低噪声放大器的设计和实验结果。该放大器采用HEMT器件三级级联,频率范围为8 500MHz~8 850 MHz,在环境温度大约20K的环境下,噪声温度小于11K,输入输出回波损耗小于-25dB,功耗小于25mW,0~40GHz内无条件稳定。 相似文献
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中介绍了S波段低温低噪声放大器的研制.在15K左右的环境温度下,300MHz带宽内,实测放大器的等效噪声温度≤4.6K,增益≥35dB,增益平坦度≤1.0clB,输入、输出回波损耗≤-20dB.它已经成功运用于射电天文等领域. 相似文献
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介绍了低温低噪声放大器产品结构、功能和用途。分析了现行低温低噪声放大器相关标准的适用情况,针对噪声温度、可靠性等质量特性,提出了包含产品全部要求和内容的详细规范制定方案,研究了详细规范中性能参数、测试方法和环境试验等关键技术要素的制定。结果表明:该标准规范了低温低噪声放大器详细要求的制定方法,适用于该产品的设计、制造及质量评价。 相似文献
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超导接收前端以超导滤波器和高电子迁移率晶体管(HEMT)低温放大器构成核心微波电路,其HEMT放大器在低温下拥有极低的工作噪声,但对偏置供电的要求很高,只有在特定偏置下,系统才拥有最佳的工作稳定度、高增益和低噪声。本文针对多信道超导接收前端,设计了一种多通道、模块化,带程控通讯的超导接收前端用HEMT低噪放电控组件,为设备核心射频通道提供供电、切换和远程控制。其供电偏置可调、供电纹波≤3 mV,并提供多路TTL电平接口,支持RS485数据通讯控制,便于模块化安装,在超导接收前端分机中工作状况良好。 相似文献
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采用AnsoftHFSS高频软件设计及优化,解决了Ka波段波导-微带的宽带过渡问题,设计出Ka波段宽带高增益低噪声放大器。 相似文献
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Sun Hyok Chang Jin Soo Han Hee Sang Chung Kwangjoon Kim Je Soo Ko 《Optics Communications》2006,261(2):269-275
The characteristics of hybrid fiber amplifier (HFA) are investigated. HFA is composed of three stages: short-length EDFA pre-stage, DCF Raman amplifier, and power boosting EDFA. HFA has low noise figure, high output power, and also wide input power dynamic range. Gain control method of HFA is presented experimentally, and the transient gain excursion is suppressed to less than 0.5 dB at 3 dB channel add-drop. HFA can be used as line amplifier in optical transmission link even combined with distributed Raman amplifier due to wide input power dynamic range. The transmission performance of HFA is better than EDFA by more than 1.0 dB of Q-factor in 720 km SMF transmission. 相似文献
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In air duct noise control, Helmholtz resonators (HR) are considered as narrow band attenuators. For some applications they can be combined in line to form a wide band silencer. This study investigates the role of distance between HR side branch openings on the whole array attenuation. In the case of two resonators with same performance, the optimal distance can be calculated and corresponds to the quarter wave of HR mean frequency. On three or more HR arrays, relationships between resonators parameters and optimal lengths are much more complex. Tuning of such a device requires taking many geometrically coupled parameters into account; hence, design has to be automated. To operate this process, a 2D FEM COMSOL model has been coupled to a global MATLAB optimization solver. Among different types of constructions, arrays made of concentric resonators with transversal openings offers the most efficient and flexible design to optimize distance between openings. This methodology was applied to an existing turbo compressor silencer. Modifying openings and chambers arrangement, using the proposed approach increased the attenuation band by 10%. Another application concerning an air box for a two stroke engine was also investigated. This resulted in a 16L two chambers concept, being replaced by a more compact and more efficient, 8.3L wide band silencer, made of 8 resonators. With this approach it therefore becomes possible to handle available space and required noise attenuation on a required frequency band, all in one process. 相似文献