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Jea‐Shik Shin Insang Song Chul‐Soo Kim Moon‐Chul Lee Sang Uk Son Duck‐Hwan Kim Ho‐Soo Park Sungwoo Hwang Jae‐Sung Rieh 《ETRI Journal》2014,36(2):317-320
A balanced RF duplexer with low interference in an extremely narrow bandgap is proposed. The Long‐Term Evolution band‐7 duplexer should be designed to prevent the co‐existence problem with the WiFi band, whose fractional bandgap corresponds to only 0.7%. By implementing a hybrid bulk acoustic wave (BAW) structure, the temperature coefficient of frequency (TCF) value of the duplexer is successfully reduced and the suppressed interference for the narrow bandgap is performed. To achieve an RF duplexer with balanced Rx output topology, we also propose a novel balanced BAW Rx topology and RF circuit block. The novel balanced Rx filter is designed with both lattice‐ and ladder‐type configurations to ensure excellent attenuation. The RF circuit block, which is located between the antenna and the Rx filter, is developed to simultaneously function as a balance‐to‐unbalance transformer and a phase shift network. The size of the fabricated duplexer is as small as 2.0 mm × 1.6 mm. The maximum insertion loss of the duplexer is as low as 2.4 dB in the Tx band, and the minimum attenuation in the WiFi band is as high as 36.8 dB. The TCF value is considerably lowered to ?16.9 ppm/°C. 相似文献
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2.4GHz射频薄膜体声波谐振器的研制 总被引:1,自引:0,他引:1
提出了基于ZnO压电薄膜多层结构的2.4GHz射频薄膜体声波谐振器,并进行了研究.采用修正后的Mason等效电路模型对器件的谐振特性进行了分析和模拟.给出了采用MEMS工艺制备器件的工艺流程,并利用射频网络分析仪对实验器件进行了测试.利用多点数值拟合的方法消除射频测试中引入的寄生分布参数,提取出器件的实际参数:器件的串联谐振频率fs和并联谐振频率fp分别为2.3714GHz和2.3772GHz,相应的有效机电耦合系数为0.598%;串联谐振频率处和并联谐振频率处的Q值分别为500.3和425.5,f·Q值乘积达到1.2×1012.该谐振器器件的有效直径为200μm,样品实际尺寸为1.2mm×1.2mm×0.3mm,可用来制备体积小、高性能和低相噪的射频振荡器. 相似文献
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设计了一种小型介质双工器。它由高介电常数陶瓷介质同轴谐振器组成,其优点是体积小,成本低,各项性能指标优良,可用作450MHz频段移动通信收发信机的天线双工器。本文同时用最小二乘边界余数法计算了介质同轴谐振器中心孔偏差问题,可对加工陶瓷介质谐振器工艺过程中的误差范围及各参数值的修正提供依据。 相似文献
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Recently, photonic bandgap (PBG) structures have become one of the most interesting areas of research. These structures consist of one-, two- or three-dimensional finite periodically perforated dielectric/metallic material or ground planes that forbid the propagation of all electromagnetic waves within a particular frequency band (called the bandgap). This property permits additional control over the behaviour of electromagnetic waves. The research work was originally done in optical region, … 相似文献
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介绍了一种薄膜体声波谐振器和它的制备流程.该谐振器采用氧化锌压电薄膜作为压电材料,通过从硅片背部体刻蚀硅衬底的方法得到谐振器的支持层.为了避免残余应力引起的支持层起皱现象,采用氮化硅/二氧化硅/氮化硅复合膜作为支持层.采用直流磁控溅射的方法制备氧化锌压电薄膜,X射线衍射结果显示,氧化锌压电薄膜C轴择优取向明显,衍射峰半高宽为0.227 3°,显示出较好的结晶质量;扫描电镜观察到氧化锌垂直于薄膜表面的柱形晶粒结构,薄膜表面平整、致密.采用HP8753D射频网络分析仪对该薄膜体声波谐振器样品进行了测试,结果表明,谐振器具有明显的厚度伸缩振动模式,其基频在750 MHz左右,二次谐频在1.5 GHz左右.进一步提高氧化锌压电薄膜的性能,该谐振器可用于射频振荡源和射频前端滤波器中. 相似文献
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为解决下一代毫米波超宽带探测及雷达系统中谱段覆盖不足的问题,文中提出一款W 波段宽带波
导双工器的设计,能实现两个宽带谱段信号的分离和合并。首先提出基于波导混合网络原理的波导型双工器架
构设计;其次,结合高通滤波器结构,提出全W 波段波导双工器的优化设计;最后,基于数控CNC 技术对该W 波
段双工器进行制备。该双工器不仅能够实现宽带频分/ 频合和通道间高隔离性能,且具有高频段、易工艺实现的
简单结构。实际测试结果表明该双工器能够将W 波段划分为75~94 GHz 和94~110 GHz 两个频段(3 dB 相对带
宽分别为22.6%和15.7%),两通道内插入损耗分别约为-0. 5 dB 和-0. 6 dB,通道间隔离度基本优于-15 dB,且
实测性能均与仿真数据一致。此外,该W 波段波导双工器易被扩展至太赫兹频段应用。 相似文献