共查询到18条相似文献,搜索用时 187 毫秒
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应用新的温度补偿方法研制了100.450MHz五次泛音温度补偿晶体振荡器,该振荡器由450kHz陶瓷振荡器,100MHz五次泛音晶体振荡器,混频器,晶体滤波器组成。450kHz陶瓷振荡器的输出频率与100MHz晶体振荡器的输出频率混频,滤波,取其和频。直接利用450kHz陶瓷振荡器输出频率对100MHz晶体振荡器进行温度补偿。实验结果表明,在0~70℃该振荡器的频率-温度稳定度<±7×10-7,初步测量相位噪声为-119dBc@1kHz。 相似文献
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设计了一种新型的单基三电极石英晶体谐振器,并在大气环境条件下测试分析了这种谐振器的频率-度特性,验证了其频率-度特性与已有的单基单电极谐振器的频率-温度特性基本一致,曲线为三次曲线.在相同激励及环境条件下,在同一基片上设置多对电极时,各对电极构成的谐振器的频率-温度特性基本相同.根据这种相似特点,将同一基片上不同电极对应的谐振器的振动频率进行差频补偿,可有效地抑制温度对谐振器振动频率的影响.这种谐振器所采用的差频补偿方法可为石英谐振器相关特性的进一步开发利用提供依据.研究了这种结构的石英晶体谐振器的晶片表面处理(是否抛光)及边沿形状(是否倒边)对其频率-温度特性的影响.实验结果表明,对单基多电极石英晶体谐振器的晶片表面进行抛光并对边沿进行倒边处理后,谐振器的稳定性得到了有效的改善,性能得到了优化. 相似文献
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设计了一种新型的单基三电极石英晶体谐振器,并在大气环境条件下测试分析了这种谐振器的频率-温度特性,验证了其频率-温度特性与已有的单基单电极谐振器的频率-温度特性基本一致,曲线为三次曲线。在相同激励及环境条件下,在同一基片上设置多对电极时,各对电极构成的谐振器的频率-温度特性基本相同。根据这种相似特点,将同一基片上不同电极对应的谐振器的振动频率进行差频补偿,可有效地抑制温度对谐振器振动频率的影响。这种谐振器所采用的差频补偿方法可为石英谐振器相关特性的进一步开发利用提供依据。研究了这种结构的石英晶体谐振器的晶片表面处理(是否抛光)及边沿形状(是否倒边)对其频率-温度特性的影响。实验结果表明,对单基多电极石英晶体谐振器的晶片表面进行抛光并对边沿进行倒边处理后,谐振器的稳定性得到了有效的改善,性能得到了优化。 相似文献
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设计了一种新型的单基三电极石英晶体谐振器,并在大气环境条件下测试分析了这种谐振器的频率-温度特性,验证了其频率-温度特性与已有的单基单电极谐振器的频率-温度特性基本一致,曲线为三次曲线。在相同激励及环境条件下,在同一基片上设置多对电极时,各对电极构成的谐振器的频率-温度特性基本相同。根据这种相似特点,将同一基片上不同电极对应的谐振器的振动频率进行差频补偿,可有效地抑制温度对谐振器振动频率的影响。这种谐振器所采用的差频补偿方法可为石英谐振器相关特性的进一步开发利用提供依据。研究了这种结构的石英晶体谐振器的晶片表面处理(是否抛光)及边沿形状(是否倒边)对其频率-温度特性的影响。实验结果表明,对单基多电极石英晶体谐振器的晶片表面进行抛光并对边沿进行倒边处理后,谐振器的稳定性得到了有效的改善,性能得到了优化。 相似文献
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高稳定晶体振荡器通常由石英谐振器、振荡电路和恒温槽三部分组成,其相互关系均以满足谐振器的稳频要求为前提。本文叙述了高精密石英谐振器的主要特性,分析了这些特性与晶振频率稳定度之间的关系,且以AT切5MHz高精密谐振器为例导出可达到的最高稳频程度以及实现其稳定度的必要条件,最后对影响高稳晶振频率稳定度的诸因素进行了综合归纳。 相似文献
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圆形晶片厚度切变石英谐振器是常用的力敏谐振器。它有固定的设计谐波次数和谐振频率。文章介绍了以设计频率为三次谐波、5MHz的AT-切型谐振器为力敏元件的力传感器在不同电路中分别振动在基频、3次谐波、5次谐波和7次谐波四个谐振频率,并对其力敏特性进行了实验研究。分析了用提高谐振频率的方法提高力灵敏度的可行性和局限性。根据石英谐振器振动在不同谐振频率时力灵敏度的温度特性,找到了温度变化时由力灵敏度温度系数造成的测量误差的消除方法,分析比较了这种方法和选取特定施力方位角消除上述误差的方法之间的差别和适用范围,并找到了在一定温度范围内可同时测量力(压力)和温度的石英传感器的设计原理。 相似文献
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The study of the stability of frequency sources is a matter of major interest due to the evolution of communication and instrumentation systems resulting in increasing the number of channels in a limited spectrum, and reducing size and power consumption. The paper relates laboratory experiences that explain the behavior versus temperature of thickness-mode quartz crystal resonators (AT- and SC-cut crystals) that are applied to the control of frequency sources, and the performance of digital compensation techniques. Prototypes of microcomputer-compensated crystal oscillators (MCXO's) have been developed to compare the compensation performance using the resonator as the temperature sensor against the use of an external sensor and verify the reduction of compensation errors due to thermal lags and hysteresis. The design of a CMOS integrated circuit for the MCXO is also included. A frequency correction method that does not modify the crystal resonance has been implemented in the circuit. This allows sensing of the temperature by means of the crystal and improving its long-term stability (aging). A new frequency comparator is also introduced. Its aim is to obtain the difference between two very close frequencies at its output, without being affected by the phase variations that the new frequency correction method and the digital circuit introduce. This detector has been implemented to get a high-resolution thermometric frequency and to realize a frequency-locked loop that includes a crystal controlled local oscillator, allowing the use of the MCXO as a good short-term stability source 相似文献
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三次泛音49U/S石英谐振器因Q值高、频率牵引小、跌落性能好而被一些有特殊要求的电路所采用。三次泛音石英谐振器因谐振电阻大,难以控制成为晶片加工技术中的一个主要难题。通过对晶片的选材、切割角度的控制和晶片长度、宽度、厚度的设计以及晶片加工工艺技术的改进,进行研究和探讨。结果表明,取得了满意的效果。 相似文献
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Power semiconductors in the wind turbine power converter system suffer from two-scale thermal loadings, the fundamental frequency thermal cycling caused by the output frequency of converter and the low frequency thermal cycling due to the variation of long-term wind speed. These two-scale thermal loadings introduce different consumed lifetimes. Accurate lifetime estimation in the wind power application is desired for reliability prediction and health management. This paper adopts the Bayerer lifetime model to evaluate the consumed lifetime of power semiconductors in wind power converter systems based on a numerical junction temperature calculation method. Lifetime estimation can be improved by taking into account the ambient temperature. Studies show that fluctuations of the ambient temperature increase the consumed lifetime due to the low frequency thermal cycling, but have little effect on the consumed lifetime due to the fundamental frequency thermal cycling. Our results also show that the consumed lifetime due to fundamental frequency thermal cycling mainly falls on the high wind speed area, whereas the consumed lifetime due to low frequency thermal cycling is clustered in the area due to large low frequency junction temperature fluctuations. The resulting distribution characteristics can be used in the thermal management for reliability improvement. 相似文献
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高功率全固态激光器腔内倍频晶体KTP温度场的解析分析 总被引:1,自引:0,他引:1
在激光二极管泵浦的全固态激光器系统中谐振腔内有较高的基频光功率密度 ,非线性晶体采用腔内倍频方式可提高晶体的谐波转换效率。但是非线性晶体吸收基频光辐射也会引起内部非均匀的温升 ,导致晶体内部各点的折射率的改变 ,破坏晶体本征的位相匹配条件 ,从而影响了晶体的谐波转换效率。通过对谐振腔内非线性晶体工作状态的分析 ,利用解析的方法得出了全固态激光器中非线性晶体KTP内部温度场的精确计算方法 ,并分析了影响KTP晶体内部温度场变化的各种因素。所得出的结果具有一定的普适性 ,可以应用到具有轴对称形式内热源的其它热模型温度场的计算分析中 ,对连续波腔内倍频激光系统的设计将起到指导作用 相似文献
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《Electronics letters》2005,41(14):804-805
A dual-mode semiconductor-optical-amplifier external-cavity laser is presented. The dual-mode optical output can produce a radio frequency beat signal at 31.6 GHz with a 3 dB linewidth of 700 kHz. 相似文献
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Yamagata Sekiji Yamamoto Kazumitu Fukai Ichiro Yasuda Ichiji 《Electronics letters》1978,14(14):450-451
Thickness-shear stress distributions of a planoconvex AT-cut quartz-crystal resonator oscillating with the fundamental, 3rd overtone and 5th overtone thickness-shear vibration resonant frequencies are measured by means of a laser-beam modulation method. The measured stress distributions are compared with the stress values computed by the finite element method for a simulation study. The experimental values show good agreement with the computed stress distributions. The absolute value of the measured stress agrees with that in the experiment of Spencer. 相似文献