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Method of adaptive PLL bandwidth adjustment without phase slipping 被引量:2
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作者 Yannian Lou Chaojie Zhang +1 位作者 Xiaojun Jin Zhonghe Jin 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2014年第6期949-958,共10页
In a system based on the phase lock loop(PLL), a trade-off must be made between the tracking precision and the dynamic performance if constant parameters are adopted. To overcome this drawback, a new method called n... In a system based on the phase lock loop(PLL), a trade-off must be made between the tracking precision and the dynamic performance if constant parameters are adopted. To overcome this drawback, a new method called no phase slipping adaptive bandwidth(NPS-AB) is proposed, which can adjust the loop bandwidth adaptively for different working conditions. As a result, both the tracking precision and the dynamic performance can be achieved concurrently. NPS-AB has two features to keep the loop stable: one is the capability of quick response to dynamics; the other is a series of additional constraints when the bandwidth is switched. Compared with other methods, there is no phase slipping during the adjustment process for NPS-AB. The phase integer ambiguity can be avoided and the phase value is kept valid. It is meaningful for carrier ranging systems. Simulation results show that NPS-AB can deal with sudden dynamics and keep the pseudo-range value stable in the entire dynamic process. 展开更多
关键词 bandwidth adjustment tracking performance phase slipping adaptive loop
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Phase-Locked Loop Based Cancellation of ECG Power Line Interference
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作者 LI Taihao ZHOU Jianshe +2 位作者 LIU Shupeng SHI Jinsheng REN Fuji 《ZTE Communications》 2018年第1期47-51,共5页
Power line(PL)interference is one significant artifact in electrocardiography(ECG)that needs to be reduced to ensure accurate recording of cardiac signals.Because PL interference is non-stationary and has varying freq... Power line(PL)interference is one significant artifact in electrocardiography(ECG)that needs to be reduced to ensure accurate recording of cardiac signals.Because PL interference is non-stationary and has varying frequency,phase,and amplitude in ECG measurement,adaptive techniques are often necessary to track and cancel the interference.In this paper we present a phase-locked loop(PLL)-based adaptive filter to cancel PL interference.The PLL obtains the reference signal that is fed into the adaptive filter to remove the PL interference at the central frequency of 50 Hz.It is found that the technique can effectively cancel PL interference in real ECG signals and,when compared with some existing techniques such as least mean squares(LMS)adaptive filter,the new technique produces better results in terms of signal-to-interference ratio(SIR). 展开更多
关键词 phase-locked loop ECG adaptive FILTER power line cancella-tion
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Comparative Study of Low-Pass Filter and Phase-Locked Loop Type Speed Filters for Sensorless Control of AC Drives
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作者 Dong Wang Kaiyuan Lu +1 位作者 Peter Omand Rasmussen Zhenyu Yang 《CES Transactions on Electrical Machines and Systems》 2017年第2期207-215,共9页
High quality speed information is one of the key issues in machine sensorless drives,which often requires proper filtering of the estimated speed.This paper comparatively studies typical low-pass filters(LPF)and phase... High quality speed information is one of the key issues in machine sensorless drives,which often requires proper filtering of the estimated speed.This paper comparatively studies typical low-pass filters(LPF)and phase-locked loop(PLL)type filters with respect to ramp speed reference tracking and steady-state performances,as well as the achievement of adaptive cutoff frequency control.An improved LPF-based filter structure with no ramping and steady-state errors caused by filter parameter quantization effects is proposed,which is suitable for applying LPF for sensorless drives of AC machines,especially when fixed-point digital signal processor is selected e.g.in mass production.Furthermore,the potential of adopting PLL for speed filtering is explored.It is demonstrated that PLL type filters can well maintain the advantages offered by the improved LPF.Moreover,it is found that the PLL type filters exhibit almost linear relationship between the cutoff frequency of the PLL filter and its proportional-integral(PI)gains,which can ease the realization of speed filters with adaptive cutoff frequency for improving the speed transient performance.The proposed filters are verified experimentally.The PLL type filter with adaptive cutoff frequency can provide satisfactory performances under various operating conditions and is therefore recommended. 展开更多
关键词 adaptive cutoff frequency low-pass filter machine sensorless drive phase-locked loop speed filter static error
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Stability and Robustness Analysis of an Adaptive Algorithm for Quasi-periodic Disturbances Rejection
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作者 徐昱琳 张五一 杨向萍 《Journal of Donghua University(English Edition)》 EI CAS 2004年第6期49-53,共5页
Winding and web transport systems are subjected to quasi-periodic disturbances of the web tension due to the eccentricity and the non-circularity of the reel and rolls. The disturbances induced by the non-circularity ... Winding and web transport systems are subjected to quasi-periodic disturbances of the web tension due to the eccentricity and the non-circularity of the reel and rolls. The disturbances induced by the non-circularity and eccentricity of the rolls are quasi-periodic with a frequency that varies with their rotation speed. An adaptive method of rejection of these disturbances is proposed in this paper. It is based on a phase-locked loop structure that estimates simutaneously the phase and magnitude of the perturbation and then cancels it. This algorithm can be plugged in an existing industrial controller. The stability and robustness of the algorithm are also discussed. The ability of the algorithm to reject quasi-periodic disturbances with slowly varying frequencies is shown through simulation results. 展开更多
关键词 QUASI-PERIODIC DISTURBANCE rejection web WINDING systems adaptive algorithm phase-locked loop STABILITY and robustness analysis
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A 3.96 GHz phase-locked loop for mode-1 MB-OFDM UWB hopping carrier generation
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作者 郑永正 李伟男 +2 位作者 夏玲琍 黄煜梅 洪志良 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2009年第7期91-95,共5页
A fully integrated phase-locked loop(PLL) is presented for a single quadrature output frequency of 3.96 GHz.The proposed PLL can be applied to mode-1 MB-OFDM UWB hopping carrier generation.An adaptive frequency cali... A fully integrated phase-locked loop(PLL) is presented for a single quadrature output frequency of 3.96 GHz.The proposed PLL can be applied to mode-1 MB-OFDM UWB hopping carrier generation.An adaptive frequency calibration loop is incorporated into the PLL.The capacitance area in the loop filter is largely reduced through a capacitor multiplier.Implemented in a CMOS process, this PLL draws 13.0 mA current from a single 1.2 V supply while occupying 0.55 mm2 die area.Measurement results show that the PLL achieves a phase noise of-70 dBc/Hz at 10 kHz offset and-113 dBc/Hz at 1 MHz offset.The integrated RMS jitter from 1 kHz to 10 MHz is 2.2 ps.The reference spur level is less than-68 dBc. 展开更多
关键词 phase-locked loop adaptive frequency calibration loop filter CMOS UWB
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Short locking time and low jitter phase-locked loop based on slope charge pump control
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作者 郭仲杰 刘佑宝 +2 位作者 吴龙胜 汪西虎 唐威 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2010年第10期79-85,共7页
A novel structure of a phase-locked loop (PLL) characterized by a short locking time and low jitter is presented, which is realized by generating a linear slope charge pump current dependent on monitoring the output... A novel structure of a phase-locked loop (PLL) characterized by a short locking time and low jitter is presented, which is realized by generating a linear slope charge pump current dependent on monitoring the output of the phase frequency detector (PFD) to implement adaptive bandwidth control. This improved PLL is created by utilizing a fast start-up circuit and a slope current control on a conventional charge pump PLL. First, the fast start-up circuit is enabled to achieve fast pre-charging to the loop filter. Then, when the output pulse of the PFD is larger than a minimum value, the charge pump current is increased linearly by the slope current control to ensure a shorter locking time and a lower jitter. Additionally, temperature variation is attenuated with the temperature compensation in the charge pump current design. The proposed PLL has been fabricated in a kind of DSP chip based on a 0.35 μm CMOS process. Comparing the characteristics with the classical PLL, the proposed PLL shows that it can reduce the locking time by 60% with a low peak-to-peak jitter of 0.3% at a wide operation temperature range. 展开更多
关键词 phase-locked loop loop bandwidth phase margin phase frequency detector slope charge pump current
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GNSS载波环中环路增益的自适应调节研究 被引量:4
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作者 张晶泊 张淑芳 +2 位作者 胡青 姜毅 孙晓文 《仪器仪表学报》 EI CAS CSCD 北大核心 2012年第2期293-299,共7页
传统的GNSS(global navigation satellite system)软件接收机中,载波环路的环路增益是固定的,无法兼顾信号变化时的快速锁定和信号跟踪时的稳定输出2种不同需求。提出了一种基于自适应增益控制方法的载波环路设计方案,建立了一套环路增... 传统的GNSS(global navigation satellite system)软件接收机中,载波环路的环路增益是固定的,无法兼顾信号变化时的快速锁定和信号跟踪时的稳定输出2种不同需求。提出了一种基于自适应增益控制方法的载波环路设计方案,建立了一套环路增益控制模型,并给出了相应的数学定义。通过仿真分析,该方案能够有效地提升载波环路的暂态响应特性。最后通过软件接收机平台的实际验证,证明该方法能够在信号频率误差较大时实现快速锁定,当信号跟踪上后又能够提高输出信号的稳定性,从而在接收机的动态性能和噪声性能之间实现了较好的平衡。 展开更多
关键词 GNSS软件接收机 载波环路 环路带宽 环路增益 自适应增益控制
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INS/GPS紧耦合系统自适应跟踪环路带宽设计 被引量:5
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作者 岳亚洲 陆志东 +1 位作者 张会锁 赵国军 《中国惯性技术学报》 EI CSCD 2008年第4期458-461,共4页
在INS/GPS紧耦合系统中,通过把惯导系统的位置、速度等估计值反馈到GPS的跟踪环,使环路带宽可以变窄,以明显改善GPS的抗干扰能力。在这种组合系统中,跟踪误差是由环路带宽内中的干扰噪声、振荡器相位噪声引起,此外还有惯性传感器的误差... 在INS/GPS紧耦合系统中,通过把惯导系统的位置、速度等估计值反馈到GPS的跟踪环,使环路带宽可以变窄,以明显改善GPS的抗干扰能力。在这种组合系统中,跟踪误差是由环路带宽内中的干扰噪声、振荡器相位噪声引起,此外还有惯性传感器的误差引起的跟踪误差。文中提出了按照GPS信号的载噪比自适应地调节GPS的环路带宽的方案,这将使GPS接收机在任何条件下包括存在干扰时保持最佳状态。分析和仿真计算说明,与采用固定带宽时相比,自适应带宽的紧耦合系统具有更高的抗干扰能力和对卫星信号的跟踪精度。 展开更多
关键词 INS/GPS紧耦合 抗干扰 自适应环路带宽 载噪比
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远程高速水声通信及实验研究 被引量:8
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作者 吴芳菲 黄建国 何成兵 《计算机测量与控制》 CSCD 北大核心 2010年第8期1837-1839,共3页
严重受限的带宽是导致目前远程水声通信系统数据率较低的主要原因,针对这一问题,提出了带宽利用率高的相位相干远程高速水声通信方法;利用8PSK和16QAM信号进行了远程(30km)海上实验研究,结果表明,采用内嵌二阶锁相环的自适应判决反馈均... 严重受限的带宽是导致目前远程水声通信系统数据率较低的主要原因,针对这一问题,提出了带宽利用率高的相位相干远程高速水声通信方法;利用8PSK和16QAM信号进行了远程(30km)海上实验研究,结果表明,采用内嵌二阶锁相环的自适应判决反馈均衡器接收机可消除慢变水声信道的影响,在距离为30km,误码率在10^(-3)内的条件下,数据率可达1200 bit/s和1600 bit/s。 展开更多
关键词 高速水声通信 自适应均衡器 带宽利用率 二阶数字锁相环
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一种深空再生复合伪码测距信号的自适应捕获跟踪技术 被引量:2
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作者 姚飞 匡麟玲 +1 位作者 衡量 陆建华 《宇航学报》 EI CAS CSCD 北大核心 2009年第1期266-270,共5页
再生复合伪码非常适合于深空测距。分析了复合伪码的相关特性和典型伪码跟踪环的结构,提出了一种通过相位误差过零检测进行码环带宽自适应调整的算法,进而实现测距信号的自适应捕获和跟踪。仿真结果表明算法能使环路的相位误差方差减小6... 再生复合伪码非常适合于深空测距。分析了复合伪码的相关特性和典型伪码跟踪环的结构,提出了一种通过相位误差过零检测进行码环带宽自适应调整的算法,进而实现测距信号的自适应捕获和跟踪。仿真结果表明算法能使环路的相位误差方差减小6~7倍。 展开更多
关键词 深空测距 复合伪码 延迟锁定环 自适应带宽调整
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A High Purity Integer-N Frequency Synthesizer in 0.35μm SiGe BiCMOS
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作者 张健 李志强 +2 位作者 陈立强 陈普峰 张海英 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2008年第4期655-659,共5页
An integer-N frequency synthesizer in 0.35μm SiGe BiCMOS is presented. By implementing different building blocks with different types of devices,a high purity frequency synthesizer with excellent spur and phase noise... An integer-N frequency synthesizer in 0.35μm SiGe BiCMOS is presented. By implementing different building blocks with different types of devices,a high purity frequency synthesizer with excellent spur and phase noise performance has been realized. All the building blocks are implemented with differential topology except for the off-chip loop filter. To further reduce the phase noise,bonding wires are used to form the resonator in the LC-VCO. The frequency synthesizer operates from 2.39 to 2.72GHz with output power of about 0dBm. The measured closed-loop phase noise is - 95dBc/Hz at 100kHz offset and - 116dBc/Hz at 1MHz offset from the carrier. The power level of the reference spur is less than - 72dBc. With a 3V power supply, the whole chip including the output buffers consumes 60mA. 展开更多
关键词 SiGe BiCMOS phase-locked loop high purity loop bandwidth
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可自适应调节带宽的新型非线性二阶锁相环 被引量:3
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作者 赵蕾 石磊 +1 位作者 朱从莹 姚博 《电子科技》 2019年第1期1-4,10,共5页
大捕获带宽的同步给传统二阶锁相环带来了巨大挑战。文中针对传统锁相环捕获带宽与抑制噪声能力两者之间的矛盾,提出一种耦合非线性环节的新型二阶锁相环,利用非线性模块自适应调整环路噪声带宽。输入输出相位误差较大时利用较大的带宽... 大捕获带宽的同步给传统二阶锁相环带来了巨大挑战。文中针对传统锁相环捕获带宽与抑制噪声能力两者之间的矛盾,提出一种耦合非线性环节的新型二阶锁相环,利用非线性模块自适应调整环路噪声带宽。输入输出相位误差较大时利用较大的带宽迅速减小频偏;当相位误差由于环路控制作用而减小时,利用较小的带宽抑制噪声以提高跟踪精度。仿真结果表明,非线性二阶锁相环跟踪速度显著提高,且相比传统二阶锁相环,捕获带宽从4 kHz最大提高到18. 8 kHz。 展开更多
关键词 锁相环 捕获带宽 跟踪精度 自适应 频率相位误差 环路噪声带宽
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基于DSP Builder的带宽自适应全数字锁相环的设计与实现 被引量:1
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作者 李勇 朱立军 单长虹 《现代电子技术》 2010年第16期1-4,共4页
提出一种设计全数字锁相环的新方法,采用基于PI控制算法的环路滤波器,在分析模拟锁相环系统的数学模型的基础上,建立了带宽自适应全数字锁相环的数学模型。使用DSP Builder在Matlab/Simulink环境下搭建系统模型,并采用FPGA实现了硬件电... 提出一种设计全数字锁相环的新方法,采用基于PI控制算法的环路滤波器,在分析模拟锁相环系统的数学模型的基础上,建立了带宽自适应全数字锁相环的数学模型。使用DSP Builder在Matlab/Simulink环境下搭建系统模型,并采用FPGA实现了硬件电路。软件仿真和硬件测试的结果证明了该设计的正确性和易实现性。该锁相环具有锁频速度快、频率跟踪范围宽的特点。同时,系统设计表明基于DSP Builder的设计方法可缩短设计周期,提高设计的灵活性。 展开更多
关键词 DSP BUILDER 带宽自适应 PI控制 全数字锁相环
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GNSS接收机自适应带宽伪码跟踪环路设计 被引量:4
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作者 刘盟超 赵丙风 《无线电通信技术》 2017年第4期64-66,79,共4页
从GNSS接收机对伪码延迟锁定环(DLL)快速稳定的需求出发,分析了环路滤波器带宽对码环性能的影响,对不同带宽下环路的稳定时间和跟踪精度进行了测试。提出了一种自适应带宽的码环设计方案,通过对环路滤波器带宽的实时调整,有效地实现了... 从GNSS接收机对伪码延迟锁定环(DLL)快速稳定的需求出发,分析了环路滤波器带宽对码环性能的影响,对不同带宽下环路的稳定时间和跟踪精度进行了测试。提出了一种自适应带宽的码环设计方案,通过对环路滤波器带宽的实时调整,有效地实现了码环牵引过程的快速稳定和精确跟踪,提升了码环性能。利用自研的GNSS接收机进行了测试和验证,测试结果表明码环稳定时间小于400 ms。 展开更多
关键词 延迟锁定环路 稳定时间 自适应带宽 GNSS
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A fast lock frequency synthesizer using an improved adaptive frequency calibration 被引量:2
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作者 阴亚东 阎跃鹏 +1 位作者 梁伟伟 杜占坤 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2010年第6期131-136,共6页
An improved adaptive frequency calibration(AFC) has been employed to implement a fast lock phaselocked loop based frequency synthesizer in a 0.18μm CMOS process.The AFC can work in two modes:the frequency calibrat... An improved adaptive frequency calibration(AFC) has been employed to implement a fast lock phaselocked loop based frequency synthesizer in a 0.18μm CMOS process.The AFC can work in two modes:the frequency calibration mode and the store/load mode.In the frequency calibration mode,a novel frequency-detector is used to reduce the frequency calibration time to 16 us typically.In the store/load mode,the AFC makes the voltage-controlled oscillator(VCO) return to the calibrated frequency in about 1μs by loading the calibration result stored after the frequency calibration.The experimental results show that the VCO tuning frequency range is about 620-920 MHz and the in-band phase noise within the loop bandwidth of 10 kHz is-82 dBc/Hz.The lock time is about 20μs in frequency calibration mode and about 5 us in store/load mode.The synthesizer consumes 12 mA from a single 1.8 V supply voltage when steady. 展开更多
关键词 adaptive frequency calibration frequency detector frequency synthesizer phase-locked loop
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基于卡尔曼滤波的抗电离层闪烁跟踪算法研究
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作者 夏俊 周必磊 +2 位作者 宋涛 刘阳 岳富占 《上海航天》 CSCD 2018年第1期30-35,共6页
针对电离层闪烁可引起星载GPS接收机传统锁相环(PLL)跟踪环路测量误差增大从而降低接收机定位及测速精度的问题,引入自适应带宽环路,提出一种基于卡尔曼滤波的抗电离层闪烁载波跟踪环路,给出了卡尔曼滤波跟踪环路结构与建模过程,主要包... 针对电离层闪烁可引起星载GPS接收机传统锁相环(PLL)跟踪环路测量误差增大从而降低接收机定位及测速精度的问题,引入自适应带宽环路,提出一种基于卡尔曼滤波的抗电离层闪烁载波跟踪环路,给出了卡尔曼滤波跟踪环路结构与建模过程,主要包括系统模型与观测模型的建模过程。采用AJ-Stanford电离层闪烁模型生成闪烁数据,仿真分析不同强度的幅度闪烁,比较基于卡尔曼滤波的跟踪环路与传统PLL跟踪环路的性能,卡尔曼环路的鉴相值标准差与载波相位误差均比传统PLL环路小。仿真结果表明:当幅度闪烁时,基于卡尔曼滤波的跟踪环路鲁棒性与跟踪精度均优于传统的PLL环路。 展开更多
关键词 星载GPS接收机 电离层闪烁 AJ-Stanford模型 幅度闪烁 跟踪环路 锁相环 自适应带宽环路 卡尔曼滤波
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自适应带宽锁相环建模分析与验证 被引量:2
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作者 沈广振 杨煜 赵玉月 《电子与封装》 2020年第3期27-32,共6页
基于UMC 40 nm CMOS工艺,进行了自适应带宽锁相环的设计。根据自适应带宽锁相环原理和结构特点,对自适应带宽锁相环常用架构进行分析,并详细阐述自适应带宽锁相环系统模型。针对锁相环各模块引入噪声对输出信号噪声的贡献进行分析,并根... 基于UMC 40 nm CMOS工艺,进行了自适应带宽锁相环的设计。根据自适应带宽锁相环原理和结构特点,对自适应带宽锁相环常用架构进行分析,并详细阐述自适应带宽锁相环系统模型。针对锁相环各模块引入噪声对输出信号噪声的贡献进行分析,并根据分析结果对其系统和噪声进行Matlab建模分析,最后通过测试验证了Matlab建模分析的结果。 展开更多
关键词 自适应带宽锁相环 系统分析 噪声 Matlab建模
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Jitter Reduced Self Biased PLLs—A Systematic Simulation Study
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作者 J. Dhurga Devi 《Circuits and Systems》 2016年第5期533-542,共10页
The self biased Phase Locked Loop (PLL) has become a default choice for clock generation in many microprocessors. In today’s scenario, the processor cores are made to operate at rapidly varying combinations of clock ... The self biased Phase Locked Loop (PLL) has become a default choice for clock generation in many microprocessors. In today’s scenario, the processor cores are made to operate at rapidly varying combinations of clock frequencies and very low supply voltages. Though the traditional self biased PLL is still being widely used with hardly any modification, it is becoming imperative to take a relook at the design aspects of these PLLs with respect to their jitter performance. This paper presents a systematic simulation study of designing the self biased PLL with the goal of reducing jitter. It further shows that if the self biased PLL is adapted into a dual loop scheme in a systematic manner, a significant jitter improvement can be obtained. Detailed simulations carried out in 0.18 μm CMOS technology indicate a reduction of 56% or more in jitter for the systematically designed dual loop scheme in comparison to the jitter reduced traditional self biased PLL. 展开更多
关键词 JITTER Dual loop PLL Self Biased PLL adaptive bandwidth PLL
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自适应光学系统波前校正残余误差的功率谱分析方法 被引量:10
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作者 饶长辉 沈锋 姜文汉 《光学学报》 EI CAS CSCD 北大核心 2000年第1期68-73,共6页
采用比较自适应光学系统闭环校正前后时间功率谱的方法, 对自适应光学系统的波前校正残余误差进行了分析。在注意系统噪声时, 实测的闭环波前复原相位误差与实际波前校正残余误差是有区别的, 分析了两者功率谱的差别之后, 提出了一种估... 采用比较自适应光学系统闭环校正前后时间功率谱的方法, 对自适应光学系统的波前校正残余误差进行了分析。在注意系统噪声时, 实测的闭环波前复原相位误差与实际波前校正残余误差是有区别的, 分析了两者功率谱的差别之后, 提出了一种估计实际波前校正残余误差的方法。应用这种方法对1.2 展开更多
关键词 自适应光学 大气湍流 功率谱 噪声 波前残余误差
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自适应光学系统倾斜校正回路的最优闭环带宽 被引量:4
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作者 郭友明 马晓燠 饶长辉 《物理学报》 SCIE EI CAS CSCD 北大核心 2014年第6期425-429,共5页
基于实际自适应光学系统倾斜校正回路最常使用的比例积分控制器,分析了最优闭环带宽与大气湍流、测量噪声之间的关系.利用满足Kolmogorov湍流整体倾斜功率谱密度的时间序列进行了相关的数值仿真.结果表明,根据不同湍流强度及测量噪声选... 基于实际自适应光学系统倾斜校正回路最常使用的比例积分控制器,分析了最优闭环带宽与大气湍流、测量噪声之间的关系.利用满足Kolmogorov湍流整体倾斜功率谱密度的时间序列进行了相关的数值仿真.结果表明,根据不同湍流强度及测量噪声选择合适的闭环带宽,可以充分发挥自适应光学系统倾斜校正回路的闭环校正能力,减小闭环残差. 展开更多
关键词 自适应光学 倾斜校正 Tyler频率 最优闭环带宽
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