共查询到18条相似文献,搜索用时 156 毫秒
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本文提出一种基于平面螺旋微带的2.45GHz小功率电感耦合微波等离子体源,根据等效变压器耦合模型分析等离子体源的谐振特性,通过微波等离子体吸收功率与等离子体阻抗之间的关系,研究不同气压条件下的放电规律.研究表明,在低气压条件下,输入功率不超过220mW时,空气开始放电;而在常压条件下,输入功率不超过1.5W时,氩气开始放电;随着微波等离子体的激励,小功率微波等离子体源的谐振频率和S参数都发生变化.这为电感耦合微波等离子体源的小型化研究提供了理论基础. 相似文献
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基于MEMS平面螺旋电感和MEMS可调平行板电容设计并制作了一种宽可调范围的集成可调带通滤波器。理论分析并计算了可调滤波器电感和可调电容的取值范围,利用HFSS设计得到各元件结构参数,并使用AnsoftDesigner分析软件对可调滤波器电路进行了模拟仿真。设计得到的可调滤波器中心频率调节范围为400~700MHz,可调率达75%,实现了宽范围可调,3dB相对带宽范围为5%~10%,插入损耗小于5dB,芯片尺寸为20mm×6mm×0.4mm。给出了一套基于MEMS平面工艺的MEMS集成可调滤波器的制作流程,实现了MEMS集成可调滤波器的工艺制作及测试。测试结果表明,获得的可调滤波器实现了通带频率宽范围可调。 相似文献
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为了实现电感-电容压控振荡器(LC VCO)的全集成和小面积,同时使其振荡频率具有较宽的可调范围和较低的相位噪声,采用差分有源电感和Q值增强共源共栅电路结构,对LC VCO进行设计。采用差分有源电感代替螺旋电感,减小了芯片面积,并利用有源电感的可调性,增大了振荡频率的可调范围。采用Q值增强共源共栅电路结构,增加了LC VCO的输出功率和Q值,进而减小了相位噪声。基于TSMC 0.18 μm RF CMOS工艺,采用Cadence仿真工具对LC VCO进行仿真验证。结果表明,LC VCO振荡频率的可调范围高达129%,在偏离最大振荡频率1 MHz处,最低相位噪声为-121.4 dBc/Hz,直流功耗为11 mW,优值FOMT(考虑到调谐范围)为-193.6 dBc/Hz。 相似文献
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微波等离子体灯是利用微波能激发等离子体发光的新型光源。微波等离子灯射频模块的工作频率是在420~470MHz范围内可调,其输出功率平坦度越小越好。基于锁相环频率合成原理,使用ADI公司的集成芯片ADF4350设计了满足要求的频率源。最终通过设计PCB、制板、电装并调试制作了满足要求的频率源的。最终测试结果表明,输出平均功率为5dBm,功率平坦度小于0.2dB,杂散抑制在50dBc以上。 相似文献
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提出了一种新型的定频波束可调微带漏波天线.通过在微带漏波天线的辐射边缘周期性地加载微带电感,可减小微带漏波天线的相位常数,进而减小微带漏波天线的主波束方向角.微带电感是一末端短路的短微带线.应用时域有限差分法(FDTD)对这种加栽微带电感的微带漏波天线进行仿真分析得出,当频率为10.5GHz,未加载微带电感的微带漏波天线主波束方向角为53.,加载微带电感可使得微带漏波天线主波束方向角减小到11.,当减小微带电感的长度或减小微带电感间的距离时,微带漏波天线主波束方向角会减小.本文FDTD仿真结果与软件HFSS仿真结果十分吻合. 相似文献
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该文提出了一款通带独立可调的高选择性双频滤波天线。首先设计了一款微带耦合式馈电的双频带通滤波器,通过在微带馈线上引入一个金属通孔,实现源负载耦合,改善裙边选择性。同时,给出了滤波器对应的等效电路模型。在此基础上设计了一款椭圆形单极子天线,利用滤波天线综合设计方法与滤波器集成实现滤波天线。单极子天线带宽覆盖滤波器带宽,仅改变开口环电长度即可实现中心频率可调。为了验证设计加工和测试了相应天线。结果表明,天线工作在2.31 GHz与3.27 GHz时,相对带宽分别为10.3%和7.7%,增益分别为3.2 dBi和4.1 dBi,有4个辐射零点,中心频率可调范围为1.8~4.8 GHz。测量与仿真结果基本吻合。 相似文献
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射频可调谐微电感在当前发挥着重要作用,它能满足高性能紧凑型器件设计的要求。对于器件设计者来说,可调电感能调谐电感量并能保证较高或适当的品质因素(Q值),这种能力在可调谐系统中比可调电容更有优势,因为可调电容可靠性较低并且大量占用基片面积。可调电感能节省芯片面积,它为将来便携式通讯系统所需的大范围可调谐系统提供一个优选的方案。因此,从器件角度对可调电感进行综述。根据可调电感的调谐机制,可调电感可分为四大类:离散型、金属屏蔽型、磁芯调谐型和线圈耦合型。对文献报道的可调电感进行概括,讨论这些可调电感优点和缺点,同时也介绍了这些可调电感的制备工艺、结果比较和其应用等。 相似文献
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An X-band active integrated antenna push-pull power amplifier is presented that uses a dual feed microstrip leaky-wave antenna for both out-of-phase power combining and second harmonic tuning. This novel structure results in a compact and high efficiency power amplifier design. At the operating frequency of 8.7 GHz. A maximum measured PAE of 54% at an output power of 38.1 dBm has been achieved 相似文献
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Mueller C.H. Lee R.Q. Romanofsky R.R. Kory C.L. Lambert K.M. Van Keuls F.W. Miranda F.A. 《Antennas and Propagation, IEEE Transactions on》2008,56(5):1236-1241
A small-sized active integrated antenna (AIA), consisting of a transmission feedback oscillator loaded with a microstrip antenna is presented in this paper. The oscillator antenna, which consists of a NEC super low noise high frequency field effect transistor (HF FET) integrated into the center of a segmented patch antenna, was designed for X-band at 8.50 GHz, and occupies a 5 times 6 mm2 area. The active integrated antenna demonstrates stable oscillations and excellent radiation patterns at X-band design frequencies. When biased using a single 1.5 volt battery connected between the source and drain and with the gate terminal open, the antenna effective isotropic radiated power (EIRP) and direct current (DC)-to-radiated radio frequency (RF) conversion efficiency are +11.2 dBm and 10.5%, respectively. The radiated power level and directivity are +4.5 dBm and 6.7 dBi, respectively. The phase noise at 100 kHz offset from the carrier is -87.5 dBc/Hz, which is a notable improvement over existing AIA designs. The AIA features compact size and simple geometry, yet provides radiated power levels and radiation efficiencies that are comparable to values typically obtained using circuits that occupy larger areas, and use thicker substrates with much lower dielectric constant values. 相似文献
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Jinho Jeong Youngwoo Kwon 《Microwave and Wireless Components Letters, IEEE》2004,14(10):457-459
A V-band 1/2 frequency divider is developed using harmonic injection-locked oscillator. The cross-coupled field effect transistors (FETs) and low quality-factor microstrip resonator are employed as a wide-band oscillator to extend the locking bandwidth. The second harmonic of free-running oscillation signal is injected to the gates of cross-coupled FETs for high-sensitivity superharmonic injection locking. The fabricated microwave monolithic integrated circuit frequency divider using 0.15-/spl mu/m GaAs pHEMT process showed a maximum locking range of 7.4 GHz (from 65.1 to 72.5 GHz) under a low power dissipation of 100 mW. The maximum single-ended output power was as high as -3 dBm. 相似文献
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提出了一种薄膜电阻加载的矩形螺旋型谐振器,并利用其设计了一种甚小尺寸的微带均衡器子结构电路,对薄膜电阻的加载位置也进行了研究.通过在螺旋型谐振器中引入电阻加载,使得该电路能够进行品质因数调节.利用高频结构仿真软件分析表明这种电阻加载的螺旋型谐振器不仅能够进行中心频率调节、曲线衰减幅度调节,而且能够对谐振回路的品质因数进行调节,适合在微带均衡器中应用,为微带均衡器的设计提供了一种新的设计途径. 相似文献
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Xiao Li Yong Zhang Oupeng Li Yan Sun Haiyan Lu Wei Cheng Ruimin Xu 《Journal of Infrared, Millimeter and Terahertz Waves》2017,38(2):166-175
In this paper, a novel design of frequency tripler monolithic microwave integrated circuit (MMIC) using complementary split-ring resonator (CSRR) is proposed based on 0.5-μm InP DHBT process. The CSRR-loaded microstrip structure is integrated in the tripler as a part of impedance matching network to suppress the fundamental harmonic, and another frequency tripler based on conventional band-pass filter is presented for comparison. The frequency tripler based on CSRR-loaded microstrip generates an output power between ?8 and ?4 dBm from 228 to 255 GHz when the input power is 6 dBm. The suppression of fundamental harmonic is better than 20 dBc at 77–82 GHz input frequency within only 0.15?×?0.15 mm2 chip area of the CSRR structure on the ground layer. Compared with the frequency tripler based on band-pass filter, the tripler using CSRR-loaded microstrip obtains a similar suppression level of unwanted harmonics and higher conversion gain within a much smaller chip area. To our best knowledge, it is the first time that CSRR is used for harmonic suppression of frequency multiplier at such high frequency band. 相似文献