Pub Date : 2001-06-06DOI: 10.1109/FREQ.2001.956332
H. Fang, J.S. Yang
The flexural vibration of an elastic beam with surface bonded piezoelectric films rotating about its axis is studied. One-dimensional equations governing the motion of the beam are developed, including the effects of Coriolis and centrifugal forces. The equations are employed in the analysis of the flexural vibration of the beam under the excitation of an alternating electric voltage. Forced vibration solution is obtained. It is shown that the beam can be used as a gyroscope for detecting the angular rate of the rotation. Voltage sensitivity and its dependence on various geometric and physical parameters are examined.
{"title":"Vibration analysis of a rotating elastic beam with piezoelectric films as an angular rate sensor","authors":"H. Fang, J.S. Yang","doi":"10.1109/FREQ.2001.956332","DOIUrl":"https://doi.org/10.1109/FREQ.2001.956332","url":null,"abstract":"The flexural vibration of an elastic beam with surface bonded piezoelectric films rotating about its axis is studied. One-dimensional equations governing the motion of the beam are developed, including the effects of Coriolis and centrifugal forces. The equations are employed in the analysis of the flexural vibration of the beam under the excitation of an alternating electric voltage. Forced vibration solution is obtained. It is shown that the beam can be used as a gyroscope for detecting the angular rate of the rotation. Voltage sensitivity and its dependence on various geometric and physical parameters are examined.","PeriodicalId":369101,"journal":{"name":"Proceedings of the 2001 IEEE International Frequncy Control Symposium and PDA Exhibition (Cat. No.01CH37218)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2001-06-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124937064","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2001-06-06DOI: 10.1109/FREQ.2001.956159
Thomas B. Swanson, Eric A. Burt, C. Ekstrom
We have performed an initial characterization of the stability of the U.S. Naval Observatory (USNO) cesium fountain atomic clock. This device has a short-term fractional frequency stability of up to 1.5/spl times/10/sup -13/ /spl tau/-/sup 1/2/. This short-term performance enables us to measure hydrogen maser behavior over the short to medium term. We have recently implemented real time steering of a hydrogen maser with the fountain. Over a period of roughly 9 days of continuous operation, we have steered out the drift of a cavity tuned maser.
{"title":"Characterization of the USNO cesium fountain","authors":"Thomas B. Swanson, Eric A. Burt, C. Ekstrom","doi":"10.1109/FREQ.2001.956159","DOIUrl":"https://doi.org/10.1109/FREQ.2001.956159","url":null,"abstract":"We have performed an initial characterization of the stability of the U.S. Naval Observatory (USNO) cesium fountain atomic clock. This device has a short-term fractional frequency stability of up to 1.5/spl times/10/sup -13/ /spl tau/-/sup 1/2/. This short-term performance enables us to measure hydrogen maser behavior over the short to medium term. We have recently implemented real time steering of a hydrogen maser with the fountain. Over a period of roughly 9 days of continuous operation, we have steered out the drift of a cavity tuned maser.","PeriodicalId":369101,"journal":{"name":"Proceedings of the 2001 IEEE International Frequncy Control Symposium and PDA Exhibition (Cat. No.01CH37218)","volume":"8 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2001-06-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122406602","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2001-06-06DOI: 10.1109/FREQ.2001.956362
Mitsunori Dendal, Y. Yong
The two-dimensional time-harmonic Boundary Element Method (BEM) for the general anisotropy is presented and applied to the eigen frequency analysis of quartz resonators. The use of the time-harmonic fundamental solution provides a clean boundary only formulation of the BEM without domain integrals. The resulting eigenvalue problem, given by a full matrix with each element depending nonlinearly on the frequency, is reduced to a generalized linear eigenvalue problem, which is solved by the QZ algorithm. Numerical results are presented for eigenvalue analysis of quartz and compared with existing FEM and analytical solutions. The proposed BEM equals or surpasses the performance of the FEM in its accuracy.
{"title":"2-D time-harmonic BEM for general anisotropy applied to eigenvalue analysis of quartz resonators","authors":"Mitsunori Dendal, Y. Yong","doi":"10.1109/FREQ.2001.956362","DOIUrl":"https://doi.org/10.1109/FREQ.2001.956362","url":null,"abstract":"The two-dimensional time-harmonic Boundary Element Method (BEM) for the general anisotropy is presented and applied to the eigen frequency analysis of quartz resonators. The use of the time-harmonic fundamental solution provides a clean boundary only formulation of the BEM without domain integrals. The resulting eigenvalue problem, given by a full matrix with each element depending nonlinearly on the frequency, is reduced to a generalized linear eigenvalue problem, which is solved by the QZ algorithm. Numerical results are presented for eigenvalue analysis of quartz and compared with existing FEM and analytical solutions. The proposed BEM equals or surpasses the performance of the FEM in its accuracy.","PeriodicalId":369101,"journal":{"name":"Proceedings of the 2001 IEEE International Frequncy Control Symposium and PDA Exhibition (Cat. No.01CH37218)","volume":"38 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2001-06-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132558741","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2001-06-06DOI: 10.1109/FREQ.2001.956173
E. Ivanov, L. Hollberg, S. Diddams
The goal this work was to study the limitations imposed on frequency stability of synthesised optical signal by intrinsic fluctuations of the femtosecond laser as well as fluctuations in the optical readout system.
本工作的目的是研究飞秒激光的固有波动以及光学读出系统的波动对合成光信号频率稳定性的限制。
{"title":"Experimental study of noise properties of a Ti-sapphire mode-locked laser","authors":"E. Ivanov, L. Hollberg, S. Diddams","doi":"10.1109/FREQ.2001.956173","DOIUrl":"https://doi.org/10.1109/FREQ.2001.956173","url":null,"abstract":"The goal this work was to study the limitations imposed on frequency stability of synthesised optical signal by intrinsic fluctuations of the femtosecond laser as well as fluctuations in the optical readout system.","PeriodicalId":369101,"journal":{"name":"Proceedings of the 2001 IEEE International Frequncy Control Symposium and PDA Exhibition (Cat. No.01CH37218)","volume":"63 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2001-06-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130313870","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2001-06-06DOI: 10.1109/FREQ.2001.956164
W. Nagourney
We feel that continuing advancement of the state of the art of single ion trapping and laser technology will make a single laser-cooled ion a viable candidate for a time or frequency standard in the very near future. The recent achievements in flywheel laser technology and the use of femtosecond "comb" lasers to bridge the optical-microwave gap are very important steps in this direction. These advances together with the well-known advantages of,an optical frequency and small systematics should make the prospects for a single-ion optical standard very favorable indeed.
{"title":"Optical time and frequency standard based on single indium ion","authors":"W. Nagourney","doi":"10.1109/FREQ.2001.956164","DOIUrl":"https://doi.org/10.1109/FREQ.2001.956164","url":null,"abstract":"We feel that continuing advancement of the state of the art of single ion trapping and laser technology will make a single laser-cooled ion a viable candidate for a time or frequency standard in the very near future. The recent achievements in flywheel laser technology and the use of femtosecond \"comb\" lasers to bridge the optical-microwave gap are very important steps in this direction. These advances together with the well-known advantages of,an optical frequency and small systematics should make the prospects for a single-ion optical standard very favorable indeed.","PeriodicalId":369101,"journal":{"name":"Proceedings of the 2001 IEEE International Frequncy Control Symposium and PDA Exhibition (Cat. No.01CH37218)","volume":"40 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2001-06-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116474786","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2001-06-06DOI: 10.1109/FREQ.2001.956165
J. Deng
An extremely small and inexpensively manufactured physics package for an atomic frequency standard can be provided with a microwave cavity having non-critical dimensions that is driven in a substantially TEM mode by a lumped LC structure inside a hollow, substantially closed, conducting enclosure. The enclosure can be a cylinder with rectangular or circular cross section. If this cavity is formed by modifying a coaxial cavity, the outer conductor will be the enclosure, and the inner conductor, shorted to at least one of the walls, with a gap at the other end, will be the lumped LC. The resonant frequency of the cavity is primarily determined by the capacitance of the lumped C and the inductance of the inner conductor.
{"title":"Subminiature microwave cavity for atomic frequency standards","authors":"J. Deng","doi":"10.1109/FREQ.2001.956165","DOIUrl":"https://doi.org/10.1109/FREQ.2001.956165","url":null,"abstract":"An extremely small and inexpensively manufactured physics package for an atomic frequency standard can be provided with a microwave cavity having non-critical dimensions that is driven in a substantially TEM mode by a lumped LC structure inside a hollow, substantially closed, conducting enclosure. The enclosure can be a cylinder with rectangular or circular cross section. If this cavity is formed by modifying a coaxial cavity, the outer conductor will be the enclosure, and the inner conductor, shorted to at least one of the walls, with a gap at the other end, will be the lumped LC. The resonant frequency of the cavity is primarily determined by the capacitance of the lumped C and the inductance of the inner conductor.","PeriodicalId":369101,"journal":{"name":"Proceedings of the 2001 IEEE International Frequncy Control Symposium and PDA Exhibition (Cat. No.01CH37218)","volume":"9 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2001-06-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125246591","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2001-06-06DOI: 10.1109/FREQ.2001.956287
O. Bel, R. Bourquin
In a perfect vibrating beam gyrometer the sensing mode of vibration is only excited by the Coriolis effect and it is assumed that the sensing electrodes do not respond to the primary mode of vibration. This is the case if the shape of the vibrating beam and of the electrodes don't exhibit geometric defects. In this paper we consider, in a practical point of view, the effect of geometrical defects, like misalignment, of electrodes. These defects can induce a non zero output signal (called the bias) when the gyrometer doesn't rotate and, in a less part, an alteration of the scale factor. We restrict our attention to small defects, which induce only a small dissymmetry of electrodes with respect to the symmetric axis of the beam. The method used to compute the amplitude of vibration, as well as the output current, needs to determine the static electric field in the cross section of the sensor. To do that we use an approximated method based on the decomposition of the electric potential in Fourier series. Although we here consider a tuning fork device, all what is presented is obviously valid for a single beam rate sensor.
{"title":"Effect of geometrical electrode defects on the bias and sensitivity of tuning fork angular rate sensor","authors":"O. Bel, R. Bourquin","doi":"10.1109/FREQ.2001.956287","DOIUrl":"https://doi.org/10.1109/FREQ.2001.956287","url":null,"abstract":"In a perfect vibrating beam gyrometer the sensing mode of vibration is only excited by the Coriolis effect and it is assumed that the sensing electrodes do not respond to the primary mode of vibration. This is the case if the shape of the vibrating beam and of the electrodes don't exhibit geometric defects. In this paper we consider, in a practical point of view, the effect of geometrical defects, like misalignment, of electrodes. These defects can induce a non zero output signal (called the bias) when the gyrometer doesn't rotate and, in a less part, an alteration of the scale factor. We restrict our attention to small defects, which induce only a small dissymmetry of electrodes with respect to the symmetric axis of the beam. The method used to compute the amplitude of vibration, as well as the output current, needs to determine the static electric field in the cross section of the sensor. To do that we use an approximated method based on the decomposition of the electric potential in Fourier series. Although we here consider a tuning fork device, all what is presented is obviously valid for a single beam rate sensor.","PeriodicalId":369101,"journal":{"name":"Proceedings of the 2001 IEEE International Frequncy Control Symposium and PDA Exhibition (Cat. No.01CH37218)","volume":"3 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2001-06-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128906559","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2001-06-06DOI: 10.1109/FREQ.2001.956365
P. Stockwell, C. McNeilage, M. Mossammaparast, D. Green, J. Searls
The performance of a compact sapphire microwave oscillator under vibration is measured in three orthogonal axes, and net vibration sensitivity is determined as less than 5 /spl times/ 10/sup -10/ per g. This result is compared with the vibration sensitivity of other oscillator technologies reported in the literature, together with other important oscillator characteristics.
{"title":"3-axis vibration performance of a compact sapphire microwave oscillator","authors":"P. Stockwell, C. McNeilage, M. Mossammaparast, D. Green, J. Searls","doi":"10.1109/FREQ.2001.956365","DOIUrl":"https://doi.org/10.1109/FREQ.2001.956365","url":null,"abstract":"The performance of a compact sapphire microwave oscillator under vibration is measured in three orthogonal axes, and net vibration sensitivity is determined as less than 5 /spl times/ 10/sup -10/ per g. This result is compared with the vibration sensitivity of other oscillator technologies reported in the literature, together with other important oscillator characteristics.","PeriodicalId":369101,"journal":{"name":"Proceedings of the 2001 IEEE International Frequncy Control Symposium and PDA Exhibition (Cat. No.01CH37218)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2001-06-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131208871","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2001-06-06DOI: 10.1109/FREQ.2001.956247
H. Iwata, T. Takahashi, O. Ishii
We miniaturized a very high frequency (VHF) fundamental AT-cut resonator by flip-chip bonding that joins a turned crystal chip to a ceramic package with gold bumps. The dimensions of the new resonator are 3.8 mm long /spl times/3.8 mm wide /spl times/0.9 mm high. The capacity of the resonator is a quarter of that of a conventional resonator that uses wire bonding. Moreover, we observe high stability in the 155 MHz resonator with a vibrating area of 10 /spl mu/m thickness. The new resonator is unaffected by stress and contamination due to bonding. Therefore, in the frequency vs. temperature characteristics, hysteresis errors are less than or equal to 1 ppm in the temperature cycle ranging from -40/spl deg/C to +85/spl deg/C. In the accelerated aging characteristics at an ambient temperature of +85/spl deg/C, the frequency shift is less than 1 ppm up to 6,000 hours.
{"title":"VHF fundamental AT-cut resonators using flip-chip bonding","authors":"H. Iwata, T. Takahashi, O. Ishii","doi":"10.1109/FREQ.2001.956247","DOIUrl":"https://doi.org/10.1109/FREQ.2001.956247","url":null,"abstract":"We miniaturized a very high frequency (VHF) fundamental AT-cut resonator by flip-chip bonding that joins a turned crystal chip to a ceramic package with gold bumps. The dimensions of the new resonator are 3.8 mm long /spl times/3.8 mm wide /spl times/0.9 mm high. The capacity of the resonator is a quarter of that of a conventional resonator that uses wire bonding. Moreover, we observe high stability in the 155 MHz resonator with a vibrating area of 10 /spl mu/m thickness. The new resonator is unaffected by stress and contamination due to bonding. Therefore, in the frequency vs. temperature characteristics, hysteresis errors are less than or equal to 1 ppm in the temperature cycle ranging from -40/spl deg/C to +85/spl deg/C. In the accelerated aging characteristics at an ambient temperature of +85/spl deg/C, the frequency shift is less than 1 ppm up to 6,000 hours.","PeriodicalId":369101,"journal":{"name":"Proceedings of the 2001 IEEE International Frequncy Control Symposium and PDA Exhibition (Cat. No.01CH37218)","volume":"10 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2001-06-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128990202","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2001-06-06DOI: 10.1109/FREQ.2001.956387
V. Stofanik, Igor Balaz, M. Minárik
A a direct digital frequency synthesizer incorporating compensation of frequency versus temperature (f-T) dependency of reference crystal oscillator is presented. The frequency instability of the synthesizer is /spl plusmn/0.1 ppm in a wide temperature range (-40/spl deg/C to +85/spl deg/C).
{"title":"Digitally temperature compensated DDS","authors":"V. Stofanik, Igor Balaz, M. Minárik","doi":"10.1109/FREQ.2001.956387","DOIUrl":"https://doi.org/10.1109/FREQ.2001.956387","url":null,"abstract":"A a direct digital frequency synthesizer incorporating compensation of frequency versus temperature (f-T) dependency of reference crystal oscillator is presented. The frequency instability of the synthesizer is /spl plusmn/0.1 ppm in a wide temperature range (-40/spl deg/C to +85/spl deg/C).","PeriodicalId":369101,"journal":{"name":"Proceedings of the 2001 IEEE International Frequncy Control Symposium and PDA Exhibition (Cat. No.01CH37218)","volume":"118 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2001-06-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126140251","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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