共查询到20条相似文献,搜索用时 62 毫秒
1.
Entesari K. Obeidat K. Brown A.R. Rebeiz G.M. 《Microwave Theory and Techniques》2007,55(11):2399-2405
This paper presents a state-of-the-art discrete RF microelectromechanical systems (MEMS) tunable filter designed for 25-75-MHz operation. This paper also presents an enhanced model of the RF MEMS switch, which is used for accurate prediction of the tunable filter response. The two-pole lumped-element filter is based on digital capacitor banks with on-chip metal-contact RF MEMS switches and lumped inductors, and results in a tuning range of 3:1 with fine frequency resolution, and a return loss better than 13 dB for the entire tuning range. The relative bandwidth of the filter is 4 plusmn 1% over the tuning range and the insertion loss is 3-5 dB, limited mostly by the inductor Q and the switch loss. The IIP3 measurements prove that tunable filters with metal-contact series RF MEMS switches show extremely linear behavior (IIP3 > 68 dBm). 相似文献
2.
在介绍数字调谐式射频跳频滤波器电路结构设计原理的基础上,描述了以HP VEE软件平台和GPIB接口技术构建的MDTF数字调谐式射频跳频滤波器的自动调试系统的设计原理,该系统在研制MDTF数字调谐式射频跳频滤波器的过程中,完成了矫正、候选生成、测试、筛选、在线测试、离线测试等6大部分的调试功能。 相似文献
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This paper presents a low power tunable active inductor and RF band pass filter suitable for multiband RF front end circuits. The active inductor circuit uses the PMOS cascode structure as the negative transconductor of a gyrator to reduce the noise voltage. Also, this structure provides possible negative resistance to reduce the inductor loss with wide inductive bandwidth and high resonance frequency. The RF band pass filter is realized using the proposed active inductor with suitable input and output buffer stages. The tuning of the center frequency for multiband operation is achieved through the controllable current source. The designed active inductor and RF band pass filter are simulated in 180 nm and 45 nm CMOS process using the Synopsys HSPICE simulation tool and their performances are compared. The parameters, such as resonance frequency, tuning capability, noise and power dissipation, are analyzed for these CMOS technologies and discussed. The design of a third order band pass filter using an active inductor is also presented. 相似文献
4.
《Microwave Theory and Techniques》2005,53(8):2566-2571
This paper presents a state-of-the-art RF microelectromechanical systems (MEMS) wide-band tunable filter designed for the 12–18-GHz frequency range. The coplanar-waveguide filter, fabricated on a glass substrate using loaded resonators with RF MEMS capacitive switches, results in a tuning range of 40% with very fine resolution, and return loss better than 10 dB for the whole tuning range. The relative bandwidth of the filter is$hbox5.7pm hbox0.4hbox%$ over the tuning range and the size of the filter is 8 mm$, times ,4$ mm. The insertion loss is 5.5 and 8.2 dB at 17.8 and 12.2 GHz, respectively, for a 2-$hboxkOmega/hboxsq$ bias line. The loss improves to 4.5 and 6.8 dB at 17.8 and 12.2 GHz, respectively, if the bias line resistance is increased to 20$hboxkOmega/hboxsq$ . The measured$ IIP_3$ level is$≫$ 37 dBm for$Delta f ≫ 200$ kHz. To our knowledge, this is the widest band planar tunable filter to date. 相似文献
5.
声光可调滤光器(AOTF)是未来全光网络中实现波长路由选择的首选器件。具有独特的多通道操作功能,可同时选择多个波长及快速调谐。要实现AOTF的可调波长选路功能,对驱动功率源有较高的要求。本文介绍了我们研制的一种可调谐通道射频功率源,其中采用声表面波谐振器制作的频率源具有较大的调谐范围和较高频率稳定性。瞬时频率稳定度达到10^-8;单通道输出功率可达1W,能满足AOTF的操作要求。 相似文献
6.
A novel tunable microwave photonic FIR filter incorporating a wavelength spacing tunable multiwavelength filter based on a programmable arrayed micro-mirror device (AMMD) is demonstrated. Owing to the unique characteristic of the AMMD, that an arbitrary optical filter shape can be produced by defining a desired spatial pattern on an array of /spl sim/800 000 micro-mirrors, a wavelength spacing tunable multiwavelength optical filtering pattern is readily obtainable. By controlling the optical filter wavelength spacing, flexible resonance RF frequency tuning is achieved over a range of 2.3 GHz. 相似文献
7.
A new photonic RF phase shifter structure for phased array antennas is presented. It is based on a single dual-output modulator and two optical switches and optical attenuators. This can realize continuous phase shifting of 0/spl deg/-360/spl deg/ without altering the signal amplitude. It has the advantages of wide bandwidth, fast response time, and fine tuning resolution. Experimental results demonstrate phase shifts over a 360/spl deg/ phase range, with RF signal power changes of less than 0.2 dB, which is in close agreement with predictions. A tunable photonic RF notch filter, which is based on the new phase shifter, is also presented. Experimental results demonstrate continuous tuning of the photonic notch filter over a wide tuning range, which covers the full free spectral range, which is in good agreement with predictions. 相似文献
8.
X-band RF MEMS tuned combline filter 总被引:1,自引:0,他引:1
Nordquist C.D. Goldsmith C.L. Dyck C.W. Kraus G.M. Finnegan P.S. Austin F. Sullivan C.T. 《Electronics letters》2005,41(2):76-77
A three-pole combline filter tuning from 8.2 to 11.3 GHz using RF MEMS switched capacitors is reported. This structure, measuring 2.85/spl times/2.15 mm/sup 2/, allows 31% tuning with 11% 3 dB bandwidth for the four tuning states and insertion losses ranging from 4.4 to 6 dB. 相似文献
9.
提出了一种基于相位调制器(PM)和可调谐光滤波器产生线性调频激光信号的方法。该方法利用带有基频的微波线性调频信号作为相位调制器的驱动信号,窄线宽的激光种子源经相位调制器调制后产生一系列的宽带线性调频激光信号。通过可调谐光滤波器抑制其他边带保留所需阶次的线性调频激光信号。实验结果表明:当光滤波器保留正二阶调频激光信号时,获得了调频带宽为2 GHz、调频速率为6 THz/s的线性调频激光信号。在观测时间为1 ms时,测得的线性调频激光信号的瞬时线宽为3.2 kHz。该方法结构简单,易于实现,并且对调频连续波激光雷达、相干光谱分析等测量应用有重要意义。 相似文献
10.
Yu Yan Jianping Yao 《Photonics Technology Letters, IEEE》2007,19(19):1472-1474
A novel tunable photonic microwave filter with complex coefficients is proposed and experimentally demonstrated. The complex coefficient is generated using a wideband tunable optical RF phase shifter that consists of two electrooptic intensity modulators. The phase of the RF signal is shifted by simply adjusting the bias voltages applied to the two electrooptic intensity modulators, and the phase shift remains constant over the microwave spectral region of interest. A two-tap photonic microwave filter with one tunable complex coefficient, with a wide and continuous tuning range, is experimentally demonstrated. 相似文献
11.
Bantas S. Koutsoyannopoulos Y. 《Circuits and Systems II: Express Briefs, IEEE Transactions on》2004,51(2):69-76
A novel CMOS circuit for obtaining a bandpass response from a triple-coupled-inductor arrangement is presented, featuring Q-enhancement and center frequency tuning by means of vector-modulating a current flowing through one of the coupled inductors. A 0.35-/spl mu/m CMOS LC filter prototype employing the technique has been fabricated and exhibits a center frequency tuning range of 11% around 1 GHz and Q values up to 180. The input 1-dB compression point is -13 dBm with Q set to 20 and a power consumption of 12.2 mW. Additionally, an input impedance matching scheme around a spiral transformer is presented, which tracks the center frequency of the filter. The active-LC approach can be applied to higher order filter responses and find applications in tunable building blocks for agile RF front ends and multistandard radios. 相似文献
12.
设计了一种利用微波光子滤波器(MPF)实现频率可调谐的光电振荡器(OEO)。该模型通过双驱动Mach-Zehnder调制器(DD-MZM)和啁啾光栅形成高Q值的MPF,得出OEO的振荡频率是关于光源波长和DD-MZM直流偏置电压的函数,通过对光源波长或DD-MZM偏置电压的调整,可实现振荡频率调谐功能。同时,在电域上,利用RF耦合器和RF延时线形成两路具有延时差的反馈信号,通过合并后反馈至DD-MZM,从而有效地抑制边模。理论和仿真实验表明,针对不同的调谐范围可实现粗调和微调的功能。 相似文献
13.
An active recursive filter approach is proposed for the implementaion of an inductorless, tuneable RF filter in BiCMOS. A test circuit was designed and manufactured in a 0.35 μm SiGe BiCMOS technology. In simulations, the feasibility of this type of filter was demonstrated and reasonably good performance was obtained. The simulations show a center frequency tuning range from 6 to 9.4 GHz and a noise figure of 8.8 to 10.4 dB depending on center frequency. Gain and Q-value are tunable in a wide range. Simulated IIP-3 and 1-dB compression point is ?26 and ?34 dBm respectively, simulated at the center frequency 8.5 GHz and with 15 dB gain. Measurements on the fabricated device shows a center frequency tuning range from 6.6 to 10 GHz, i.e. slightly higher center frequencies were measured than the simulated. 相似文献
14.
《Microwave Theory and Techniques》2010,58(2):381-389
15.
Miraftab V. Mansour R.R. 《IEEE transactions on circuits and systems. I, Regular papers》2008,55(5):1357-1367
The paper introduces modeling of human experience by linguistic if-then rules in terms of fuzzy logic controllers for tuning RF/Microwave filters. The approach could be used for any circuit or system tuning problem that involves human expert information provided that the expert information could be described in terms of linguistic if-then rules. The tuning approach is both theoretically and practically illustrated in this paper. The tuning is done in two stages both taking advantage of fuzzy controllers. The first stage uses the phase response of the filter, while the second stage uses the magnitude response of the filter for adjustment of the tuning screws. A fully automated experimental setup is implemented by high resolution motors with flexible leads to make the tuning possible. 3-pole and 7-pole Chebyshev waveguide filters are used to demonstrate the concept. The measured results prove the validity of the method. 相似文献
16.
A continuously tunable RF/microwave photonic bandpass filter that simultaneously achieves high skirt selectivity and high stopband attenuation is presented. It is based on controlling the signal polarisation state in a reflective amplified recirculating delay line loop with a polariser at the output. A technique to overcome the phase noise limitation in the structure is also presented. Experimental results demonstrate continuous tuning of the high-performance photonic bandpass filter and a continuously tunable photonic bandpass filter with a low-noise performance. 相似文献
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Yue Wu Chunlei Shi Xiaohui Ding Mohammed Ismail Håkan Olsson 《Analog Integrated Circuits and Signal Processing》2002,33(3):239-248
In this paper, a class of CMOS biquadratic filter suitable to work at VHF/RF frequency range is presented. The proposed circuit has a simple structure which is analyzed and designed according to a universal G
m-C biquad filter. Simulation and experimental results show that these filters can work in GHz range and have wide tuning range. 相似文献