Proceedings of 1996 IEEE International Frequency Control Symposium最新文献

{"title":"A temperature compensated crystal oscillator based on analog storage method and its test system","authors":"W. Zhou, Z. Xuan, Jianguo Yu","doi":"10.1109/FREQ.1996.560243","DOIUrl":"https://doi.org/10.1109/FREQ.1996.560243","url":null,"abstract":"Analog storage (function storage) temperature compensated crystal oscillator (ASCXO) is low in price, simple in structure and high in precision. According to the similarity between cubic curve of crystal oscillator frequency control voltage-temperature sensing voltage and the voltage-time characteristics of sine waveform, the control voltage can be obtained through translating V T characteristics of sine waveform into V-V relationship. With compensation and increment regulation, the temperature compensated curve can be obtained. The test and regulation of the voltage curve are also described. ASCXO has a low demand on the accuracy of the temperature chamber, as is the case in MCXO. In the test process, we utilize measurement instead of control to simplify the equipment. When the temperature of chamber changes slowly the temperature sensing voltage and the frequency modification voltage of the oscillator are measured cyclically. Using a computer some special voltages are recorded and the reference temperature curve is obtained. After a temperature cycle experiment, the storage curve adjustment is done at room temperature. Using coincidence process of the curves the adjustment is completed by computer. One can also find out the accuracy of the oscillator at room temperature. This paper also describes some special demands upon the components. It is easy to obtain 10/sup -7/ or better frequency-temperature stability with ASCXO.","PeriodicalId":140391,"journal":{"name":"Proceedings of 1996 IEEE International Frequency Control Symposium","volume":"140 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1996-06-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122598568","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}

{"title":"A 1 GHz optical-delay-line oscillator driven by a diode laser","authors":"J. Kitching, L. Hollberg, F. Walls","doi":"10.1109/FREQ.1996.560259","DOIUrl":"https://doi.org/10.1109/FREQ.1996.560259","url":null,"abstract":"Experimental results are presented on a hybrid optical/electronic oscillator which uses an optical delay line to generate high spectral purity microwave signals. At Fourier frequencies above 10 kHz, the single sideband (SSB) phase noise spectrum decreases as roughly 1/f/sup 2/ attaining a value of -138 dB below the carrier in a 1 Hz bandwidth (dBc/Hz) at 20 kHz offset. The origin of this noise is in part the fundamental shot noise on the light itself, although other optical noise sources such as double Rayleigh scattering and stimulated Brillouin scattering also appear to be important under certain operating conditions. The frequency stability over several hours is dominated by changes in the fiber ambient temperature with a coefficient of about 10/sup -5//K originating mostly from changes in the fiber refractive index with temperature.","PeriodicalId":140391,"journal":{"name":"Proceedings of 1996 IEEE International Frequency Control Symposium","volume":"26 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1996-06-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126439516","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}

{"title":"A VHF, quartz crystal oscillator exhibiting exceptional vibration immunity","authors":"G. Labruzzo, P. Polidoro, M. Driscoll, G. Kolnowski","doi":"10.1109/FREQ.1996.559897","DOIUrl":"https://doi.org/10.1109/FREQ.1996.559897","url":null,"abstract":"This paper describes the design and performance of a 100 MHz quartz crystal oscillator employing a combination of technologies to achieve exceptionally good spectral performance under vibration. The oscillator is intended for use as the exciter master oscillator in a multi-function radar. The oscillator design utilizes two, series-connected, third overtone, SC-cut crystals oriented to provide partial cancellation of vibration occurring in the plane of the crystal blanks. The oscillator design incorporates a \"building block\" approach, including the use of a self-limiting, modular amplifier sustaining stage. In order to minimize oscillator signal spectral degradation encountered as a result of enclosure and component mechanical resonances, the following design was implemented: (1) Except for the crystals and a voltage regulator IC, the oscillator circuit employs leadless, surface mount components. (2) The use of a rigid chassis employing closely-spaced stiffening ribs which trisect both the PWA and steel covers. (3) Use of a thermally isolated but rigidly mounted crystal heater block. In addition, the oscillator assembly is designed with its center of gravity (C.G.) co-incident with the isolation system center of mass and is mounted via an elastomeric isolation system developed specifically for attenuating dynamic disturbances in small assemblies. The prototype unit produced resonant frequencies between 70 and 85 Hz with an acceleration spectral density roll-off rate up to 12 dB/octave. Oscillator at-rest phase noise is characterized by L(100 Hz)=-135 dBc/Hz and a phase noise floor level of -175 dBc/Hz. Phase noise performance under vibration measurements indicate very little degradation due to mechanical resonances. The performance that has been achieved in the region of unity transmissibility in the isolators (fm<75 Hz) corresponds to a net fractional frequency sensitivity to vibration of less than 2 to 3/spl times/10/sup -10/ per g. The corresponding sensitivity achieved for vibration occurring in the direction of the crystal blanks is on the order of 1/spl times/10/sup -10/ per g.","PeriodicalId":140391,"journal":{"name":"Proceedings of 1996 IEEE International Frequency Control Symposium","volume":"264 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1996-06-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125719683","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}

{"title":"Stress sensitivity coefficients: a general approach for bulk, Rayleigh and surface transverse waves","authors":"E. Bigler, S. Ballandras","doi":"10.1109/FREQ.1996.559891","DOIUrl":"https://doi.org/10.1109/FREQ.1996.559891","url":null,"abstract":"An analytical approach of intrinsic stress sensitivity coefficients is presented. The model is first applied to investigate the sensitivity of bulk and Rayleigh wave devices to mechanical stresses. A comparison is made with Finite Element Analysis (FEA) methods and it is shown that the stress sensitivity coefficients approach can predict the existence of stress compensated crystal cuts and correctly model the force frequency effect of a circular disk with a dramatic reduction of computation time. The model is extended to the case of Surface Transverse Waves (STW) propagating on singly-rotated quartz plates. It is shown that by a highly interesting coincidence planar isotropic stress compensation occurs for STW devices now built and tested (AT-plates). The case of planar stress sensitivity of STW devices on thin plates is considered.","PeriodicalId":140391,"journal":{"name":"Proceedings of 1996 IEEE International Frequency Control Symposium","volume":"142 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1996-06-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132186872","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}

{"title":"New type double mode SAW resonator filters on 64/spl deg/ Y-X LiNbO/sub 3/","authors":"Y. Roh, H. Kim, Y.J. Lee, M.H. Lee, K.B. Kim, K.H. Kim","doi":"10.1109/FREQ.1996.559843","DOIUrl":"https://doi.org/10.1109/FREQ.1996.559843","url":null,"abstract":"The double mode filters have the serious shortcoming that out-of-band rejection above the passband is quite poor. Hence a new structure of double mode SAW resonator filters is designed with the COM (Coupling Of Modes) theory with better out-of-band rejection characteristics while keeping all the beauties of the conventional double mode SAW filters. The second goal of the design is to reduce the planar size of the structure so that mass productivity of low frequency devices can be improved. Based on the conventional double mode filter structure, several IDT's and reflector gratings are added to or subtracted from it. As results of the investigation, several new double mode SAW resonator filter structures are developed. For the design, the effect of many design factors are investigated and the optimum values are determined. The new structure shows 10 dB more out-of-band rejection than the conventional type with 25% smaller device size. Good agreement is demonstrated between the analytical results and experimental results for an illustrative 325 MHz four pole resonator filter on 64/spl deg/ Y-X LiNbO/sub 3/.","PeriodicalId":140391,"journal":{"name":"Proceedings of 1996 IEEE International Frequency Control Symposium","volume":"109 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1996-06-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131245997","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}

{"title":"GPS frequency transfer using carrier phase measurements","authors":"Girard Petit, Claudine Thomas","doi":"10.1109/FREQ.1996.560307","DOIUrl":"https://doi.org/10.1109/FREQ.1996.560307","url":null,"abstract":"GPS time transfer is usually carried out with C/A code measurements using the common-view technique. An uncertainty of a few nanoseconds can be obtained for an integration time of about 1000 seconds when ionospheric measurements and precise orbits are used. This limits the capability of frequency comparison to the level of 3 parts in 10/sup 14/ for an integration time of one day. Recently new frequency standards have been developed that claim an accuracy at or below 1/spl times/10/sup -14/. For existing time transfer techniques it is a challenge to compare their frequency over a sufficiently short interval. Previous studies have already shown the potential of carrier-phase and P-code measurements from geodetic GPS receivers. This paper draws up tentative uncertainty budgets for clock frequency comparisons using phase and code measurements from commercially available dual-frequency and multi-channel GPS receivers. Although the level of noise involved in carrier phase measurements is two or three orders of magnitude lower than that of code measurements in the short term, other error sources such as tropospheric delay of GPS signals, multipath propagation and the phase ambiguity problem lead to a limitation in the accuracy of frequency transfer at the 10/sup -15/ level over an averaging time of one day. Carrier phase measurements, however, provide an improvement over the performance expected from code measurements for all averaging times smaller than one day.","PeriodicalId":140391,"journal":{"name":"Proceedings of 1996 IEEE International Frequency Control Symposium","volume":"98 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1996-06-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134371474","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}

{"title":"Growth and characterization of optical grade synthetic quartz","authors":"C. Suzuki, M.S. Tanaka, A. H. Shinohara","doi":"10.1109/FREQ.1996.559822","DOIUrl":"https://doi.org/10.1109/FREQ.1996.559822","url":null,"abstract":"A method to position the seed and Z-region of growth out of the circulating micro-particle flux in commercial autoclave has been used to grow optical grade synthetic quartz. The number of solid inclusions is in the range of 0.02-0.03 particles/cm/sup 3/, depending on the bar. The observation of X-ray topographic contrast of (0003) reflection shows a much smaller Z-region lattice spacing (strain) in comparison with the seed. The dislocation lines are in their totality originated by the seed etch-channels, that means, they can be eliminated by using a better quality seed.","PeriodicalId":140391,"journal":{"name":"Proceedings of 1996 IEEE International Frequency Control Symposium","volume":"47 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1996-06-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131641469","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}

{"title":"The investigation of the real structure and mechanical stresses in berlinite and langasite crystals","authors":"V. Naumov, I. Kalashnikova, O. P. Aleshko-ozhevskij","doi":"10.1109/FREQ.1996.559830","DOIUrl":"https://doi.org/10.1109/FREQ.1996.559830","url":null,"abstract":"The structural perfection of the berlinite (AlPO/sub 4/) and the langasite (La/sub 3/Ga/sub 5/SiO/sub 14/) crystals have been investigated with the help of X-ray topography. The inclusions, dislocations and different types of twins have been observed. The influence of the uniaxial stress along the crystallographic X and Y directions on the change of the light polarization plane rotation in these crystals have been studied. The appearance of two types of the circular birefringence: the screw and axial types have been found. The method of the separation of these effects have been developed, that have allowed to increase the sensitivity of the method of control of the internal stresses in crystals.","PeriodicalId":140391,"journal":{"name":"Proceedings of 1996 IEEE International Frequency Control Symposium","volume":"188 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1996-06-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132198163","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}

{"title":"Extending the range for precision AM noise measurements","authors":"C. Nelson, F. Walls, C. Boggs","doi":"10.1109/FREQ.1996.560266","DOIUrl":"https://doi.org/10.1109/FREQ.1996.560266","url":null,"abstract":"Developed as an extension of the existing NIST phase noise measurement system, the AM measurement system presently covers carrier frequencies from 5 MHz to 70 GHz. Our new technique relies on a wideband AM modulator to calibrate frequency dependent errors. The system, utilizing a double-balanced mixer as the detector, works in two passes. In the first pass, the modulator is used to sweep a known modulation level across the Fourier frequencies of interest. This level is detected by three different spectrum analyzers that cover Fourier frequencies from 1 Hz to 1 GHz. The data is then compiled into a calibration curve that is used to correct frequency dependent errors in the noise data measured in the second pass. The entire system is computer controlled via the GPIB bus enabling measurements to be made with minimal user intervention.","PeriodicalId":140391,"journal":{"name":"Proceedings of 1996 IEEE International Frequency Control Symposium","volume":"4 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1996-06-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133276144","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}

{"title":"Design considerations of vacuum-sealed OCXO's for high reliability applications","authors":"R. Clark, A. Scalpi","doi":"10.1109/FREQ.1996.559898","DOIUrl":"https://doi.org/10.1109/FREQ.1996.559898","url":null,"abstract":"It is well known that the use of a vacuum sealed enclosure which contains the crystal and oscillator circuitry can be of significant value in enhancing the performance of OCXO's. This paper reports on the design of a new vacuum sealed OCXO termed the EMXO having the design objectives of (1) a design which allows for the use of several different crystal enclosures, including the standard TO-8, (2) a parts count reduction of approximately 50% over previous designs and (3) a provision to utilize high reliability components such as class \"S\" on ceramic construction. The resulting oven thermal resistance measured approximately 180/spl deg/C/W thereby yielding a steady state power dissipation of less than 1 W at -55/spl deg/C.","PeriodicalId":140391,"journal":{"name":"Proceedings of 1996 IEEE International Frequency Control Symposium","volume":"1986 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1996-06-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131075908","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}