Pub Date : 2008-05-19DOI: 10.1109/FREQ.2008.4623051
Li Gun, Wu Fu-ping, Wei Jing-fa, Huang Xian-he
A highly precise and multifunctional timing system using the self development integrated GPS/BD time receiver is presented in this paper. The authors firstly designed an integrated GPS/BD (compass or Beidou navigation system of China) time receiver for time and frequency synchronization in a local network, and describing the main issues and the solution of the receiver implement in detail, and then focused on performance considerations. The receiver has been used as the major part to implement the timing system. The timing system can offer precise time code and frequency signal including standard frequency signal 5 MHz and 10 MHz, 1 pps and the serial time code data et al. The common view comparison technique is used in each sub-system for eliminating the common error of sources, and the observation data can be transferred between each station by wireless or internet. To keep the time synchronous precision within 10 ns between the master station and any slave station according to the observation results, phase shifting control and frequency division have been used which exploit their full level of performance. With the timing system, time comparisons are performed with a precision of 7.4 ns for a short baselines and 6.6 ns for a super short baseline. The result of traveling clock experiment indicates that the synchronous precision was 2.7 ns. The frequency stability of one second, 1.3 E-12 was achieved. The timing system can be used to supply high time and frequency signal for radar tracking, communication system, power grid and intelligent transportation system etc.
{"title":"Development of high precision and multifunctional timing system using integrated GPS/BD receiver","authors":"Li Gun, Wu Fu-ping, Wei Jing-fa, Huang Xian-he","doi":"10.1109/FREQ.2008.4623051","DOIUrl":"https://doi.org/10.1109/FREQ.2008.4623051","url":null,"abstract":"A highly precise and multifunctional timing system using the self development integrated GPS/BD time receiver is presented in this paper. The authors firstly designed an integrated GPS/BD (compass or Beidou navigation system of China) time receiver for time and frequency synchronization in a local network, and describing the main issues and the solution of the receiver implement in detail, and then focused on performance considerations. The receiver has been used as the major part to implement the timing system. The timing system can offer precise time code and frequency signal including standard frequency signal 5 MHz and 10 MHz, 1 pps and the serial time code data et al. The common view comparison technique is used in each sub-system for eliminating the common error of sources, and the observation data can be transferred between each station by wireless or internet. To keep the time synchronous precision within 10 ns between the master station and any slave station according to the observation results, phase shifting control and frequency division have been used which exploit their full level of performance. With the timing system, time comparisons are performed with a precision of 7.4 ns for a short baselines and 6.6 ns for a super short baseline. The result of traveling clock experiment indicates that the synchronous precision was 2.7 ns. The frequency stability of one second, 1.3 E-12 was achieved. The timing system can be used to supply high time and frequency signal for radar tracking, communication system, power grid and intelligent transportation system etc.","PeriodicalId":220442,"journal":{"name":"2008 IEEE International Frequency Control Symposium","volume":"17 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-05-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123790281","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 : 2008-05-19DOI: 10.1109/FREQ.2008.4622949
D. Puccio, E. P. Eernisse
This work is a continuation of an earlier study on drive level dependence (DLD), wherein the resistance of a thickness-shear crystal changes at low drive levels as the drive level changes. The earlier work used a 2-D Finite Element Analysis (FEA) to show that a surface irregularity, such as an attached particle, causes rotational imbalance in the motion of a contoured thickness-shear crystal, which transfers motional energy from the trapped shear motion to flexural motion. The flexural motion transports motional energy to the mounts. Degradation in the Q due to this increased edge motion was inferred. This degradation in Q was strongly dependent on the location of the surface irregularity in the 2-D FEA model. The present work extends the analysis to 3-D FEA using an SC resonator along with a four-point clip mount with polyimide bonding agent. Damped eigenfrequency analysis is used to include loss in the mounting structure and directly calculate eigenmode Q as a function of the location of an attached particle on the resonator surface. The results are very informative. A 4.0E-11 kg mass can change the Q by up to 30%. The magnitude of the effect is strongly dependent on the lateral location of the mass on the surface. For example, the magnitude of the effect can change significantly between two points on the blank surface only 20 microns apart.
{"title":"Finite Element Analysis of thickness shear crystals with surface irregularities","authors":"D. Puccio, E. P. Eernisse","doi":"10.1109/FREQ.2008.4622949","DOIUrl":"https://doi.org/10.1109/FREQ.2008.4622949","url":null,"abstract":"This work is a continuation of an earlier study on drive level dependence (DLD), wherein the resistance of a thickness-shear crystal changes at low drive levels as the drive level changes. The earlier work used a 2-D Finite Element Analysis (FEA) to show that a surface irregularity, such as an attached particle, causes rotational imbalance in the motion of a contoured thickness-shear crystal, which transfers motional energy from the trapped shear motion to flexural motion. The flexural motion transports motional energy to the mounts. Degradation in the Q due to this increased edge motion was inferred. This degradation in Q was strongly dependent on the location of the surface irregularity in the 2-D FEA model. The present work extends the analysis to 3-D FEA using an SC resonator along with a four-point clip mount with polyimide bonding agent. Damped eigenfrequency analysis is used to include loss in the mounting structure and directly calculate eigenmode Q as a function of the location of an attached particle on the resonator surface. The results are very informative. A 4.0E-11 kg mass can change the Q by up to 30%. The magnitude of the effect is strongly dependent on the lateral location of the mass on the surface. For example, the magnitude of the effect can change significantly between two points on the blank surface only 20 microns apart.","PeriodicalId":220442,"journal":{"name":"2008 IEEE International Frequency Control Symposium","volume":"78 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-05-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114280878","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 : 2008-05-19DOI: 10.1109/FREQ.2008.4623003
W. Wilson, D. Perey, G. Atkinson, R. Barclay
NASA aeronautical programs require integrated vehicle health monitoring (IVHM) to ensure the safety of the crew and the vehicles. Future IVHM sensors need to be small, light weight, inexpensive, and wireless. Surface acoustic wave (SAW) technology meets all of these constraints. In addition it operates in harsh environments and over wide temperature ranges, and it is inherently radiation hardened. This paper presents a survey of research opportunities for universities and industry to develop new sensors that address anticipated IVHM needs for aerospace vehicles. Potential applications of passive wireless SAW sensors from ground testing to high altitude aircraft operations are presented, along with some of the challenges and issues of the technology.
{"title":"Passive wireless SAW sensors for IVHM","authors":"W. Wilson, D. Perey, G. Atkinson, R. Barclay","doi":"10.1109/FREQ.2008.4623003","DOIUrl":"https://doi.org/10.1109/FREQ.2008.4623003","url":null,"abstract":"NASA aeronautical programs require integrated vehicle health monitoring (IVHM) to ensure the safety of the crew and the vehicles. Future IVHM sensors need to be small, light weight, inexpensive, and wireless. Surface acoustic wave (SAW) technology meets all of these constraints. In addition it operates in harsh environments and over wide temperature ranges, and it is inherently radiation hardened. This paper presents a survey of research opportunities for universities and industry to develop new sensors that address anticipated IVHM needs for aerospace vehicles. Potential applications of passive wireless SAW sensors from ground testing to high altitude aircraft operations are presented, along with some of the challenges and issues of the technology.","PeriodicalId":220442,"journal":{"name":"2008 IEEE International Frequency Control Symposium","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-05-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133229579","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 : 2008-05-19DOI: 10.1109/FREQ.2008.4622965
N. Coluccelli, G. Galzerano, P. Laporta, L. Bonelli, A. Toncelli, A. Di Lieto, M. Tonelli, V. Calabrese, M. Norgia, A. Pesatori, C. Svelto
In this work a longitudinally pumped, widely tunable, solid state Yb:YLF laser was developed with special design for applications to optical frequency metrology, LIDAR measurements in the atmosphere and for absolute frequency stabilization. The YLF crystalline host, combined with efficient diode pumping, allows for wide wavelength tunability at around 1.03 mum. The novel laser source is being thoroughly characterized in terms of output power, spatial beam quality, single frequency output, and wavelength tunability.
{"title":"Novel diode pumped Yb:KYF4 and Yb:YLF4 lasers for optical frequency metrology at 1 μm / 0.5 μm","authors":"N. Coluccelli, G. Galzerano, P. Laporta, L. Bonelli, A. Toncelli, A. Di Lieto, M. Tonelli, V. Calabrese, M. Norgia, A. Pesatori, C. Svelto","doi":"10.1109/FREQ.2008.4622965","DOIUrl":"https://doi.org/10.1109/FREQ.2008.4622965","url":null,"abstract":"In this work a longitudinally pumped, widely tunable, solid state Yb:YLF laser was developed with special design for applications to optical frequency metrology, LIDAR measurements in the atmosphere and for absolute frequency stabilization. The YLF crystalline host, combined with efficient diode pumping, allows for wide wavelength tunability at around 1.03 mum. The novel laser source is being thoroughly characterized in terms of output power, spatial beam quality, single frequency output, and wavelength tunability.","PeriodicalId":220442,"journal":{"name":"2008 IEEE International Frequency Control Symposium","volume":"17 11 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-05-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132294124","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 : 2008-05-19DOI: 10.1109/FREQ.2008.4622985
W. Zhou, Xiaoli Liu
This paper introduces four kinds of 2 GHz surface transverse wave resonators with low insertion loss, low Q on Y-rotated cuts of quartz perpendicular to the x-axis. There are same configure and number of transducers, reflector number, metal thickness via wave length.There are only difference that the number of short grating, and result in much difference. One of these can be 2.493 GHz, 7.8 dB of insertion loss, 4.89 MHz bandwith of 3 dB.
{"title":"2GHz STW resonators of low insertion loss, low Q","authors":"W. Zhou, Xiaoli Liu","doi":"10.1109/FREQ.2008.4622985","DOIUrl":"https://doi.org/10.1109/FREQ.2008.4622985","url":null,"abstract":"This paper introduces four kinds of 2 GHz surface transverse wave resonators with low insertion loss, low Q on Y-rotated cuts of quartz perpendicular to the x-axis. There are same configure and number of transducers, reflector number, metal thickness via wave length.There are only difference that the number of short grating, and result in much difference. One of these can be 2.493 GHz, 7.8 dB of insertion loss, 4.89 MHz bandwith of 3 dB.","PeriodicalId":220442,"journal":{"name":"2008 IEEE International Frequency Control Symposium","volume":"22 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-05-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114865806","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 : 2008-05-19DOI: 10.1109/FREQ.2008.4623000
Brice Ivira, Alexandre Reinhardt, Emmanuel Defay, M. Aid
This paper deals with the development of newly reported Bulk Acoustic Wave (BAW) resonators using electrostrictive Barium Strontium Titanate (BST) oxide thin films for GHz applications. Electrostriction enables tuning acoustic parameters according to a large DC bias which is superimposed over a small RF signal. As a result, such a BAW resonator behaves like conventional piezoelectric BAW but RF electrical responses can be switched OFF or tuned once turned ON. One of the major challenges is to achieve electromechanical coupling and quality factors as good as AlN-based BAW. This study gives preliminary results in terms of modeling for electromechanical coupling optimization and experimental investigations particularly focused on integration of Ba0.7Sr0.3TiO3 in BAW resonators.
{"title":"Integration of electrostrictive Ba0.7Sr0.3TiO3 thin films into Bulk Acoustic Wave resonator for RF-frequency tuning under DC bias","authors":"Brice Ivira, Alexandre Reinhardt, Emmanuel Defay, M. Aid","doi":"10.1109/FREQ.2008.4623000","DOIUrl":"https://doi.org/10.1109/FREQ.2008.4623000","url":null,"abstract":"This paper deals with the development of newly reported Bulk Acoustic Wave (BAW) resonators using electrostrictive Barium Strontium Titanate (BST) oxide thin films for GHz applications. Electrostriction enables tuning acoustic parameters according to a large DC bias which is superimposed over a small RF signal. As a result, such a BAW resonator behaves like conventional piezoelectric BAW but RF electrical responses can be switched OFF or tuned once turned ON. One of the major challenges is to achieve electromechanical coupling and quality factors as good as AlN-based BAW. This study gives preliminary results in terms of modeling for electromechanical coupling optimization and experimental investigations particularly focused on integration of Ba0.7Sr0.3TiO3 in BAW resonators.","PeriodicalId":220442,"journal":{"name":"2008 IEEE International Frequency Control Symposium","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-05-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122700599","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 : 2008-05-19DOI: 10.1109/FREQ.2008.4623066
I. Kone, Bertrand Dubus, Lionel Buchaillot, Alexandre Reinhardt, Fabrice Casset, Marc Aid, J. F. Carpentier, Pascal Ancey
This paper describes the design of resonators using waves guided in a piezoelectric layer located above a Bragg mirror. Such a resonator is suitable for the intermediate frequency (IF) and high frequency (HF) ranges. In the IF (about 600 MHz) band, maximum quality factor is achieved when exploiting the second guided mode (analogous to the S0 Lamb wave). In the HF band (about 2 GHz), a higher order mode (similar to the S1 Lamb wave) provides high coupling factors.
{"title":"Resonator using Guided waves in a piezoelectric layer above a Bragg mirror","authors":"I. Kone, Bertrand Dubus, Lionel Buchaillot, Alexandre Reinhardt, Fabrice Casset, Marc Aid, J. F. Carpentier, Pascal Ancey","doi":"10.1109/FREQ.2008.4623066","DOIUrl":"https://doi.org/10.1109/FREQ.2008.4623066","url":null,"abstract":"This paper describes the design of resonators using waves guided in a piezoelectric layer located above a Bragg mirror. Such a resonator is suitable for the intermediate frequency (IF) and high frequency (HF) ranges. In the IF (about 600 MHz) band, maximum quality factor is achieved when exploiting the second guided mode (analogous to the S0 Lamb wave). In the HF band (about 2 GHz), a higher order mode (similar to the S1 Lamb wave) provides high coupling factors.","PeriodicalId":220442,"journal":{"name":"2008 IEEE International Frequency Control Symposium","volume":"84 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-05-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123825945","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 : 2008-05-19DOI: 10.1109/FREQ.2008.4623046
Hai Wang, Wei Zhou, Zhiqi Li, Shixiang Qian, Weining Jiang, Chunxu Wang
The short time-interval and frequency measurement are main research projects in the measurement of time and frequency. Traditional measurement methods include direct counting, analog interpolating, time-to-voltage conversion, time vernier and time-to-digital conversion. However these methods are all complicated and the instruments based on these methods are expensive. A novel method for short time-interval and frequency measurement based on delay-chain technique is presented in this paper. This method utilizes measured short time-interval or measured frequency signal to generate count gate. A delay-chain is used to delay reference frequency signal orderly. So a group of signals with phase-shifting evenly in a period of reference frequency signal are generated, and are counted respectively under the same count gate. With the average of the counts as the count of reference frequency, the decimal counting error is reduced and measurement accuracy is improved. The measurement resolution of this method for short time-interval and measurement accuracy for frequency are equal to the measurement results under condition of increasing frequency of reference frequency signal by the times of the number of delay unit in a delay-chain. An experiment demonstrates the resolution of short time-interval measurement and the accuracy of frequency measurement could be 100 ps and respectively and the theoretical measurement resolution and accuracy could be higher. Although it needs more delay units and counters in order to achieve high-accuracy measurement, this is not a problem because new device has been used, such as FPGA. This method is suitable for high-accuracy and low-cost measurement..
{"title":"A time and frequency measurement method based on delay-chain technique","authors":"Hai Wang, Wei Zhou, Zhiqi Li, Shixiang Qian, Weining Jiang, Chunxu Wang","doi":"10.1109/FREQ.2008.4623046","DOIUrl":"https://doi.org/10.1109/FREQ.2008.4623046","url":null,"abstract":"The short time-interval and frequency measurement are main research projects in the measurement of time and frequency. Traditional measurement methods include direct counting, analog interpolating, time-to-voltage conversion, time vernier and time-to-digital conversion. However these methods are all complicated and the instruments based on these methods are expensive. A novel method for short time-interval and frequency measurement based on delay-chain technique is presented in this paper. This method utilizes measured short time-interval or measured frequency signal to generate count gate. A delay-chain is used to delay reference frequency signal orderly. So a group of signals with phase-shifting evenly in a period of reference frequency signal are generated, and are counted respectively under the same count gate. With the average of the counts as the count of reference frequency, the decimal counting error is reduced and measurement accuracy is improved. The measurement resolution of this method for short time-interval and measurement accuracy for frequency are equal to the measurement results under condition of increasing frequency of reference frequency signal by the times of the number of delay unit in a delay-chain. An experiment demonstrates the resolution of short time-interval measurement and the accuracy of frequency measurement could be 100 ps and respectively and the theoretical measurement resolution and accuracy could be higher. Although it needs more delay units and counters in order to achieve high-accuracy measurement, this is not a problem because new device has been used, such as FPGA. This method is suitable for high-accuracy and low-cost measurement..","PeriodicalId":220442,"journal":{"name":"2008 IEEE International Frequency Control Symposium","volume":"46 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-05-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125868788","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 : 2008-05-19DOI: 10.1109/FREQ.2008.4623106
D. Gachon, J. Masson, E. Courjon, Y. Gruson, S. Ballandras
Bulk acoustic waves excited in thin piezoelectric films have revealed their capabilities for addressing the problem of high frequency RF filters and frequency sources (above 1 GHz). In this paper, we propose an alternative to thin film deposition consisting in single crystal wafers bonded on substrate (high quality) and thinned down, allowing for plate thickness close to 30 mum. This has been achieved on 3 inches wafers and allows for an accurate selection of the wave characteristics.
{"title":"Frequency sources and filters applications using high overtone bulk acoustic resonators exhibiting high Q.f product","authors":"D. Gachon, J. Masson, E. Courjon, Y. Gruson, S. Ballandras","doi":"10.1109/FREQ.2008.4623106","DOIUrl":"https://doi.org/10.1109/FREQ.2008.4623106","url":null,"abstract":"Bulk acoustic waves excited in thin piezoelectric films have revealed their capabilities for addressing the problem of high frequency RF filters and frequency sources (above 1 GHz). In this paper, we propose an alternative to thin film deposition consisting in single crystal wafers bonded on substrate (high quality) and thinned down, allowing for plate thickness close to 30 mum. This has been achieved on 3 inches wafers and allows for an accurate selection of the wave characteristics.","PeriodicalId":220442,"journal":{"name":"2008 IEEE International Frequency Control Symposium","volume":"15 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-05-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124873620","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 : 2008-05-19DOI: 10.1109/FREQ.2008.4623088
A. Dobrogowski, M. Kasznia
In this paper the algorithm enabling assessment of maximum time interval error (MTIE) for non-uniform sampling of time error is proposed. The reasons of non-uniform sampling are presented. Then the idea of MTIE computing for non-uniform sampled data is described. Next the details of the algorithm are presented and described.
{"title":"Algorithm of MTIE point estimate computing for non-uniform sampling of time error","authors":"A. Dobrogowski, M. Kasznia","doi":"10.1109/FREQ.2008.4623088","DOIUrl":"https://doi.org/10.1109/FREQ.2008.4623088","url":null,"abstract":"In this paper the algorithm enabling assessment of maximum time interval error (MTIE) for non-uniform sampling of time error is proposed. The reasons of non-uniform sampling are presented. Then the idea of MTIE computing for non-uniform sampled data is described. Next the details of the algorithm are presented and described.","PeriodicalId":220442,"journal":{"name":"2008 IEEE International Frequency Control Symposium","volume":"30 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-05-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127037222","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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