共查询到20条相似文献,搜索用时 0 毫秒
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研制了一款可编程6阶巴特沃斯有源RC滤波器.为提高滤波器中运算放大器的增益带宽积,设计了一种新型的前馈补偿运算放大器.为消除工艺偏差和环境变化对截止频率的影响,设计了一种片上数字控制频率调谐电路,并采用TSMC 0.18 μm CMOS工艺进行了流片.滤波器采用低通滤波结构,测试结果表明,3 dB截止频率为1~32 MHz,步进1 MHz,带内增益0 dB,带内纹波0.8 dB,2倍带宽处带外抑制不小于24 dBc,5倍带宽处带外抑制不小于68 dBc,滤波器等效输入噪声为340 nV/√Hz@1MHz,调谐误差为±3%.滤波器裸芯片面积0.87 mm×1.05 mm.采用1.8V电源电压,滤波器整体功耗小于20 mW. 相似文献
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介绍了一种基于蛙跳式低通滤波器原型综合而成的复数滤波器。该电路具有较低的灵敏度,从而提高了稳定性。滤波器的自动调谐系统具有设计简单、精度易控制等特点,并可在调谐完成后关闭,减少了功耗以及与滤波器的互扰。电路采用0.18μm CMOS工艺设计,滤波器的中心频率为4 MHz,带宽为2 MHz,增益约为0 dB,可达到约53 dB的镜像抑制比,调谐精度可以控制在3%左右,功耗为7.5 mW。 相似文献
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为了降低微波滤波器调试的难度,减少调试工作对经验的要求,提高调试的效率,在微波滤波器的调试工作中引入了计算机辅助调试技术。国外的实验及生产证明,计算机辅助调试技术在大规模的批量生产中的确可以提高生产效率,降低生产成本。本文对目前国内外这一领域的发展现状及趋势做了简要的总结。 相似文献
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Paul M. Furth 《Analog Integrated Circuits and Signal Processing》1999,19(2):197-205
Continuous-time filters implemented in subthreshold CMOS have limited operating range. When processing real acoustic stimuli, input signals exceeding this range will occasionally be encountered. We compare the response of an RLC proto-type bandpass filter based on three transconductors to that of one based on four transconductors. It is found that, in response to large slowly varying input signals, the three-transconductor design tends toward oscillation whereas the four-transconductor design is stable. Simulation and chip measurements of a four-transconductor bandpass filter implemented in a 2-m process verify these claims. The filter measures 117×416 m2, operates on ±1.25 V supplies, and consumes less than 20 nW when tuned to 1 kHz. 相似文献
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J. Sabadell C. Aldea S. Celma P. A. Martínez 《Analog Integrated Circuits and Signal Processing》2001,28(1):35-42
In this paper, a continuous-time 4th order Butterworth low-pass filter based on current-mode processing is presented for applications over the video frequency range. A new type of integrator in which both voltage and currents may be integrated is presented and used as the main active block. The filter has been implemented using a very low-cost 2.4 m CMOS process (Mietec). The whole circuit occupies 2.8 mm2 and consumes 19 mW from a ±1.5 V supply. Experimental results are given for a 4.5 MHz to 12 MHz tunable low-pass filter with 58 dB of dynamic range at 10 MHz. 相似文献
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本文针对IEEE802.15.4协议的低中频接收机,提出一种CMOS Gm-C复数滤波器。该滤波器采用具有可重构共模反馈和共模前馈功能的伪差分OTA结构。文章还提出一种基于松弛振荡器的频率调谐方法,并对OTA的非线性和频率调谐方法进行了详细分析,分析及测试结果均表明该滤波器能够实现精确调谐的功能。芯片采用标准0.35μm CMOS工艺制作,测试结果显示,滤波器消耗电流2.1mA,带内群延时波动小于0.16μs,2MHz频偏处IRR大于28dB,可以满足IEEE802.15.4协议的要求。 相似文献
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传统的电调滤波器一般采用步进电机带动滤波器调谐杆,通过调谐杆的长度变化来实现频率变化,步进电机的驱动脉冲数与滤波器的频率一一对应,即可实现电调滤波器的频率调谐功能。由于电调滤波器是一种机械传动结构,随着腔体、传动、回零、调谐杆以及温度等的变化,脉冲数与频率对应关系变差,导致通信装备使用故障甚至瘫痪。从电调滤波器的工作原理出发,提出了一套电调滤波器自动校频程序,在通信设备中运行该专用程序,即可实现电调滤波器的频率校准与记忆,从而彻底解决电调滤波器的频率偏移问题。 相似文献
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The effect of the shaping filter excess bandwidth in the performance of symbol-sampled receivers over unknown continuous-time
channels is investigated. The shaping filter overall response is divided between the transmit and receive filters. The performance
loss is determined in terms of information rate, and relative to the case of perfectly synchronized matched filtering, where
the continuous-time channel has to be known a priori. Numerical results are presented for the case of a raised cosine shaping
filter and 2- and 3-rays continuous-time channel models. We show that the losses increase with the increase of the excess
bandwidth, reaching a maximum at 100% excess bandwidth, and a minimum at no excess bandwidth. 相似文献
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在微波滤波器的计算机辅助调试技术中,必须要知道滤波器的状态参数。以往的方法主要是通过滤波器的耦合矩阵来求得它的状态参数,但计算起来相当复杂。介绍一种简单易行的提取滤波器状态参数的方法,该方法通过建立滤波器的等效电路模型,运用软件的优化拟合功能,从而提取出等效电路模型的参数值。实验证明,只要搭建的电路模型精确度较高,就能够迅速、准确地提取出滤波器的状态参数。 相似文献