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排序方式: 共有118条查询结果,搜索用时 15 毫秒
11.
《Microelectronics Journal》2015,46(2):198-206
In this paper, a highly linear CMOS low noise amplifier (LNA) for ultra-wideband applications is presented. The proposed LNA improves both input second- and third-order intercept points (IIP2 and IIP3) by canceling the common-mode part of all intermodulation components from the output current. The proposed LNA structure creates equal common-mode currents with the opposite sign by cascading two differential pairs with a cross-connected output. These currents eliminate each other at the output and improve the linearity. Also, the proposed LNA improves the noise performance by canceling the thermal noise of the input and auxiliary transistors at the output. Detailed analysis is provided to show the effectiveness of the proposed LNA structure. Post-layout circuit level simulation results using a 90 nm RF CMOS process with Spectre-RF reveal 9.5 dB power gain, -3 dB bandwidth (BW−3dB) of 8 GHz from 2.4 GHz to 10.4 GHz, and mean IIP3 and IIP2 of +13.1 dBm and +42.8 dBm, respectively. The simulated S11 is less than −11 dB in whole frequency range while the LNA consumes 14.8 mW from a single 1.2 V power supply. 相似文献
12.
设计了一种新型的微带转共面带状线(coplanarStripLine以下简称CPS)的巴伦结构。它可以应用于多种常用的介质板上,具有结构紧凑、超宽带、低损耗的特点。制作了一个两端为500微带线的背靠背电路,测试得插入损耗(S21)〉-1dB、回波损耗(S11)〈-15dB的带宽为2.7GHz~7.3GHz,S21〉-4dB、S11〈-10dB的带宽为1.4GHz~15.6GHz。 相似文献
13.
A 3.1-4.8 GHz mode-1 UWB CMOS mixer that utilizes simultaneous second- and third-order distortion cancellation is presented. The scheme is based on a new derivative superposition, employing PMOS as an auxiliary FET to cancel the second- and the third-order nonlinear currents of common-source transconductance in the mixer and gives rise to low-distortion operation for a broad range of gate-source voltage. Full Volterra series analysis of the proposed transconductance is reported to examine the effectiveness of the new technique. Simulations in a 0.13 μm CMOS technology demonstrate that IIP3 and IIP2 of the proposed mixer have 18 and 10 dB improvements, respectively, compared with conventional Gilbert-type mixer with the same power consumption. The robustness of the technique has been verified by Monte Carlo analysis. The mixer has a gain of 12 dB and noise figure of 13 dB, while drawing only 2.5 mA from 1.2 V supply voltage. 相似文献
14.
15.
Qiuzhen Wan Chunhua WangAuthor vitae 《AEUE-International Journal of Electronics and Communications》2011,65(12):1006-1011
A new low complexity ultra-wideband 3.1–10.6 GHz low noise amplifier (LNA), designed in a chartered 0.18 μm RFCMOS technology, is presented in this paper. The ultra-wideband LNA only consists of two simple amplifiers with an inter-stage inductor connected. The first stage utilizing a resistive current reuse and dual inductive degeneration techniques is used to attain a wideband input matching and low noise figure. A common source amplifier with inductive peaking technique as the second stage achieves high flat gain and wide the −3 dB bandwidth of the overall amplifier simultaneously. The implemented ultra-wideband LNA presents a maximum power gain of 15.6 dB, a high reverse isolation of −45 dB and a good input/output return losses are better than −10 dB in the frequency range of 3.1–10.6 GHz. An excellent noise figure (NF) of 2.8–4.7 dB was obtained in the required band with a power dissipation of 14.1 mW under a supply voltage of 1.5 V. An input-referred third-order intercept point (IIP3) is −7.1 dBm at 6 GHz. The chip area including testing pads is only 0.8 mm × 0.9 mm. 相似文献
16.
17.
《Ceramics International》2019,45(11):13719-13725
Anti-reflective (AR) films have been widely investigated due to their various applications in optoelectronic devices. Among all the investigation, the manufacturing method is the most popular research field which directly determines the performance of anti-reflective films. Herein, Na2HPO4 and AlCl3 mixed neutral solution were used to etch the surface of K9 glass matrix to obtain the AR structure. The morphology of SEM images indicated that subwavelength structure (SWS) was formed on the glass surface via precisely controlling the solution concentration, treatment time and temperature. Owing to the porous structure, the refractive index mutation of the interface between air and glassss can be effectively weakened. Therefore, the integral transmittance, covering the whole visible light (VIS) to near-infrared (NIR) wavelength (300–2500 nm), of glass matrix was increased remarkably to 95.77%, much higher than 87.72% of blank glass, achieving the effect of ultra-wideband anti-reflection. Particularly, the transmittance at 520 nm and 1990 nm can even reach to 99.14% and 97.86%, respectively. According to the composite analysis and reaction process, Al3+ ions act as both the regulator of the solution pH and part of the new-formed glass skeleton, resulting in the more uniform and regular SWS on the glass surface. Moreover, in virtue of -OH in silanol (Si-OH) on the expanded glass surface attracting more H2O molecules or additional silylation modification on glass surface repulsing H2O molecules, the surface characteristics of AR glass with SWS films can be easily turned between hydrophilic and hydrophobic in order to meet the requirements of various application environments. These ultra-wideband AR glasses with controllable hydrophilic and hydrophobic properties are expected to be applied in many optoelectronic fields. 相似文献
18.
本文对超宽带50 W电子战超小型行波管设计进行了介绍,其主要技术难点为超宽带设计及超小型设计。通过设计行波管高效率慢波互作用系统来进行超宽带设计,使得行波管工作频带覆盖4~18 GHz,全频带(除低端边频4~5 GHz外)输出功率典型值为50 W,其中4~5 GHz频带内输出功率达到35 W,整管效率高于33%。在保障电性能的同时,通过降低工作电压实现整管各部件微型化设计,实现整管结构尺寸的大幅度压缩,实现了功率密度的大幅度提升,突破了小型化电子战整机系统安装空间的限制,适应了更高标准的电子战应用要求。 相似文献
19.
Naeem Ahmad Jan Saad Hassan Kiani Daniyal Ali Sehrai Muhammad Rizwan Anjum Amjad Iqbal Mujeeb Abdullah Sunghwan Kim 《计算机、材料和连续体(英文)》2021,66(1):35-49
In this paper, a low cost, highly efficient and low profile monopole
antenna for ultra-wideband (UWB) applications is presented. A new inverted triangular-shape structure possessing meander lines is designed to achieve a wideband response and high efficiency. To design the proposed structure, three steps
are utilized to achieve an UWB response. The bandwidth of the proposed antenna
is improved with changing meander lines parameters, miniaturization of the
ground width and optimization of the feeding line. The measured and simulated
frequency band ranges from 3.2 to 12 GHz, while the radiation patterns are measured at 4, 5.3, 6 and 8 GHz frequency bands. The overall volume of the proposed
antenna is 26 × 25 × 1.6 mm3
; whereas the FR4 material is used as a substrate
with a relative permittivity and loss tangent of 4.3 and 0.025, correspondingly.
The peak gain of 4 dB is achieved with a radiation efficiency of 80 to 98% for
the entire wideband. Design modelling of proposed antenna is performed in
ANSYS HFSS 13 software. A decent consistency between the simulated and
measured results is accomplished which shows that the proposed antenna is a
potential candidate for the UWB applications. 相似文献
20.
This paper describes the design and verification of an ultra-wideband 6–14 GHz frequency modulated continuous wave (FMCW) primary radar system with very high range resolution. The design and measurement results of the utilized signal generator and receiver are presented. The signal generator features a 86% relative continuous tuning range and average phase noise of −106 dBc/Hz at 1 MHz offset to the carrier. The radar system utilizes a hybrid structure where the voltage controlled oscillator was fabricated using 130 nm SiGe BiCMOS technology and the lower frequency components are off-the-shelf. Free field measurements of the radar showcase an unprecedented combination of 3 cm range resolution, low phase noise and low operating frequency of 6–14 GHz for inherently higher range. 相似文献