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北京大学高功率耦合器谐振环锻炼平台是对北京大学1.3 GHz超导加速器的耦合器进行高功率测试和锻炼的平台,通过谐振环与信号源谐振来产生高功率。在谐振环工作过程中,由于外界扰动会使其共振频率发生变化,故需要对谐振环路进行频率锁定,从而维持其与信号源的共振。将PDH(Pound-Drever-Hall)技术应用在此锻炼平台上,用以锁定微波信号源与谐振环的频率。实验验证表明,该PDH反馈系统能有效维持谐振环的高增益。 相似文献
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针对窄线宽激光器输出谱线窄,难以被锁定的情况,利用F-P腔特有极窄线宽、高精细度特性对激光器谱线线宽实施压窄及频率锁定。通过设计实验方案并搭建锁频测试平台,利用F-P腔外部光反馈将窄线宽半导体激光器线宽压窄来提高锁频精度。通过监测正弦波调制下F-P腔对于4种不同直流电压下激光PZT扫频段的透射谱线,并对其分别进行解调和锁频精度测试,得到直流高压放大器电压为73 V时对窄线宽激光器进行扫频,激光器反馈锁频精度最高可达1.5 MHz。 相似文献
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线宽压窄和频率锁定是提高激光器(特别是半导体激光器)性能的重要手段。在理论分析光反馈时的半导体激光器线宽压窄和频率锁定机理的基础上,建立了一套基于高品质V型光学谐振腔的半导体激光器线宽压窄实验系统,并利用该系统开展了初步实验研究。通过对比无有光反馈情况下的V型腔的透射光扫描线形,初步验证了V型腔用于半导体激光器线宽压窄和频率锁定的可行性,为后续研究奠定了基础。 相似文献
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中性束注入弧电源的性能严重影响弧放电的稳定性和中性束加热的效率。HL-2A装置弧电源采用基于晶闸管相控调压和12脉波不控整流的线性电源技术;HL-2M测试束线弧电源采用基于超级电容和IGBT全控整流的开关电源技术。为了优化电源系统性能、改进弧放电稳定性,研究了采样频率对弧放电稳定性的影响。通过对两套电源控制系统进行建模,利用MATLAB仿真了不同采样频率下HL-2M弧流电源控制系统的阶跃响应性能和HL-2A的控制系统性能,分析了采样频率对系统性能的影响。利用离子源测试平台进行不同采样频率下的弧放电实验对仿真结果进行验证,实验结果与仿真结果一致。实验结果验证:采样频率对弧放电稳定性有很大影响,在频率可调范围内,增大采样频率,可以提高控制系统性能,优化弧放电稳定性;HL-2A弧放电不稳定的原因是晶闸管导通特性和滤波电路引起的。 相似文献
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To test superconducting cavities, a vertical test system has been designed and set up at the Institute of Modern Physics (IMP). The system design is based on VCO-PLL hardware and the NI Labview software. The test of the HWR010#2 superconducting cavity shows that the function of this test system is satisfactory for testing the low frequency cavity. 相似文献
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Gennadiy P. Ermak Anton V. Varavin Evgenij A. Alekseev 《International Journal of Infrared and Millimeter Waves》2003,24(10):1609-1615
We describe experiments resulting in the phase locking of two electrically tunable 2-mm wave sources based on active high-order IMPATT multipliers. Phase locking modes were tested on a pair of identical multiplying sources (master and slave) with the tuning ranges 138.5+/–1.5 GHz (master) and 140.0+/– GHz (slave). The phase lock loop (PLL) system is used to lock the slave source to the master source. The multipliers of this type can translate the spectra of highly stable centimeter-wave oscillators to any part of the millimeter range with the output power 100÷20 mW over the 30 to 140 GHz range without additional amplification. The phase locked sources operate over a 3% frequency band with low phase noise and rapid frequency tuning. The amplitude-frequency characteristics of the sources are presented with the locking-mode signal spectra. 相似文献
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为实现数字BPM时钟系统的锁相,设计了一种基于锁相环同步原理的低抖动、低相位噪声的时钟同步系统。根据锁相环电路工作原理,对数字BPM时钟同步系统的硬件及固件程序进行了设计,实现了外部输入时钟信号与系统内部产生的主工作时钟信号的锁相,并且时钟信号输出的频率及相位均可调整以满足后端ADC采样的要求。测试结果表明,设计可以完成对一定频率范围内变化的外部输入时钟信号的锁相,输出时钟信号抖动满足束流实验要求,为数字BPM后续算法研究提供了基础。 相似文献
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针对传统腔衰荡光谱技术浓度获取率低,提出基于双重锁定的连续波腔衰荡吸收光谱技术.通过波长调制一次谐波信号将激光器的频率锁定到C_2H_2吸收线上,同时使用PDH锁频技术将衰荡腔锁定到激光器上,从而避免了测量过程中激光器的频率漂移和腔长的抖动,使测量结果更加精确;并且,由于双重锁定,单次衰荡事件的发生率,也就是浓度信息的获取率只受衰荡时间以及重新锁定时间限制,在本试验系统中采集速率可以达到30 k Hz,可以实现对气体浓度的快速测量.为了提高信噪比,采用Kalman滤波技术,对浓度信息进行实时处理,有效抑制了噪声,根据阿伦方差分析,探测灵敏度可以达到4×10~(-9)cm~(-1)(2 s平均). 相似文献
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基于数字自激算法设计并实现的超导腔垂直测试系统提高了超导腔的垂直测试效率,为先进光源技术研发与测试平台(PAPS)的超导腔批量化生产提供了重要保障;垂直测试系统的射频前端和时钟分配系统采用了二次上下变频方案,可以在一定范围内灵活设置测试系统自激环路的工作频率,增大了该测试系统的工作带宽。利用此系统完成了1.3 GHz 9-cell超导腔的通带频率测试,结果表明,该测试系统能有效避免不同模式之间的串扰,具备较强的频率分辨能力(<800 kHz),保证多单元超导腔性能验证的进行。 相似文献
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A new spread spectrum communication system utilizing chaotic frequency modulation of sinusoidal signals is discussed. A single phase lock loop (PLL) system in the receiver is used both to synchronize the local chaotic oscillator and to recover the information signal. We study the dynamics of the synchronization process, stability of the PLL system, and evaluate the bit-error-rate performance of this chaos-based communication system. 相似文献
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K. V. Kalashnikov A. V. Khudchenko V. P. Koshelets 《Bulletin of the Russian Academy of Sciences: Physics》2013,77(1):28-31
This work is devoted to investigating new superconducting electronics elements for cryogenic phase locking loop systems. It is shown that a tunnel junction superconductor-insulator-superconductor can be successfully applied as a cryogenic phase detector for a frequency stabilization system with ultrawide bandwidth. 相似文献
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Frequency stabilization of a diode laser on the Cs D2 resonance line by the Zeeman effect in a vapor cell 总被引:3,自引:0,他引:3
N. Beverini E. Maccioni P. Marsili A. Ruffini F. Sorrentino 《Applied physics. B, Lasers and optics》2001,73(2):133-138
Hyperfine optical pumping of a Cs-vapor cell through a diode laser in frequency standards requires a high purity of the laser
emission spectrum, and a high stability of the emission frequency. We present here a frequency-locking scheme that is able
to produce a discrimination signal without any modulation, by using the dichroism induced by a magnetic field on the atomic
vapor. The larger line-width of the reference signal (Doppler-broadened) is compensated by its larger amplitude, when compared
with the saturated absorption signal. As a final result, the slope is similar, and the large line-width warrants a large locking
range, making robust the lock against external perturbations. This error signal is used to lock the frequency of an external
cavity diode laser, with a grating reflector in Littman configuration. A fast correction band is obtained by changing the
cavity length through an intra-cavity electro-optic modulator. The possible sources of instabilities of the locking point
are discussed and estimated through a simulation computer program.
Received: 28 November 2000 / Revised version: 21 May 2001 / Published online: 18 July 2001 相似文献
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针对在基波频率变化情况下传统锁相环无法进行正确锁相的问题,提出了基于同步参考坐标系的追踪型三相软件锁相环.三相电压信号(Va、Vb、Vc)经同步坐标变换后,得到两相静止坐标(Vα、Vβ)信号,再经过旋转坐标变化后获得(Vd、Vq)信号;Vq信号经过低通滤波后,进行动态信号延迟,其延迟的时间由输出的频率信号获得;把延迟前... 相似文献