Pub Date : 2012-04-23DOI: 10.1109/EFTF.2012.6502382
A. Nikonov, Y. Ivanov
Long-term stability (aging) is one of the key parameters of quartz crystal oscillator. Approximation and time series prediction methods are used to evaluate it. An improved mathematical model which allows to evaluate quartz crystal oscillators from the point of longterm stability (aging) has been developed. Evaluation of the stabilization of aging process is used as the basis for the model's algorithm. Basing on such model a software system has been developed. In process of it's development different approximation functions were considered, including procedure of selection of suitable functions as well as their applicability, forecast accuracy and reliability. Also accuracy of forecast vs. duration of aging testing was studied. In this way the developed software system allowed to reach forecast of 5xE-9 accuracy for long-term stability per year. Also, what is practically important, the developed mathematical model allows to minimize possible human errors in evaluation of subject long-term stability of precision oscillators.
{"title":"System for evaluation of long-term stability of precision quartz crystal oscillators and results of its use","authors":"A. Nikonov, Y. Ivanov","doi":"10.1109/EFTF.2012.6502382","DOIUrl":"https://doi.org/10.1109/EFTF.2012.6502382","url":null,"abstract":"Long-term stability (aging) is one of the key parameters of quartz crystal oscillator. Approximation and time series prediction methods are used to evaluate it. An improved mathematical model which allows to evaluate quartz crystal oscillators from the point of longterm stability (aging) has been developed. Evaluation of the stabilization of aging process is used as the basis for the model's algorithm. Basing on such model a software system has been developed. In process of it's development different approximation functions were considered, including procedure of selection of suitable functions as well as their applicability, forecast accuracy and reliability. Also accuracy of forecast vs. duration of aging testing was studied. In this way the developed software system allowed to reach forecast of 5xE-9 accuracy for long-term stability per year. Also, what is practically important, the developed mathematical model allows to minimize possible human errors in evaluation of subject long-term stability of precision oscillators.","PeriodicalId":6409,"journal":{"name":"2012 European Frequency and Time Forum","volume":"6 1","pages":"275-278"},"PeriodicalIF":0.0,"publicationDate":"2012-04-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73543562","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 : 2012-04-23DOI: 10.1109/EFTF.2012.6502399
P. Defraigne, Q. Baire, G. Cerretto, F. Lahaye, D. Rovera
The time-transfer technique based on Precise Point Positioning (PPP) allows the comparison of atomic clocks with precisions at the level of hundred picoseconds. This paper presents the results obtained in near real-time using satellite orbit and clock information from IGS real-time streams and from the NRCan Ultra Rapid products (EMU). These results can be considered quite interesting for the National Metrology Institutes, providing a new tool for monitoring their UTC(k)'s. Two different PPP software tools have been used in this study, namely “Atomium” developed and operated at ORB and the NRCan-PPP soon to be operated at INRIM and LNE-SYRTE-OP in near real-time mode. This paper presents a quantification of the degree of equivalence of the results obtained from the analysis conducted using each software as well as the operational web page available at the Royal Observatory of Belgium, providing PPP solutions for the comparison of UTC(k)'s in near real-time.
{"title":"Near real-time comparison of UTC(k)'s through a Precise Point Positioning approach","authors":"P. Defraigne, Q. Baire, G. Cerretto, F. Lahaye, D. Rovera","doi":"10.1109/EFTF.2012.6502399","DOIUrl":"https://doi.org/10.1109/EFTF.2012.6502399","url":null,"abstract":"The time-transfer technique based on Precise Point Positioning (PPP) allows the comparison of atomic clocks with precisions at the level of hundred picoseconds. This paper presents the results obtained in near real-time using satellite orbit and clock information from IGS real-time streams and from the NRCan Ultra Rapid products (EMU). These results can be considered quite interesting for the National Metrology Institutes, providing a new tool for monitoring their UTC(k)'s. Two different PPP software tools have been used in this study, namely “Atomium” developed and operated at ORB and the NRCan-PPP soon to be operated at INRIM and LNE-SYRTE-OP in near real-time mode. This paper presents a quantification of the degree of equivalence of the results obtained from the analysis conducted using each software as well as the operational web page available at the Royal Observatory of Belgium, providing PPP solutions for the comparison of UTC(k)'s in near real-time.","PeriodicalId":6409,"journal":{"name":"2012 European Frequency and Time Forum","volume":"32 1","pages":"349-353"},"PeriodicalIF":0.0,"publicationDate":"2012-04-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75837153","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 : 2012-04-23DOI: 10.1109/EFTF.2012.6502416
G. Grosche, O. Terra, S. Raupach, U. Sterr, H. Schnatz, A. Pape, J. Friebe, M. Riedmann, E. Rasel, S. Droste, K. Predehl, R. Holzwarth, T. Udem
Optical frequency transmission via phase-stabilized telecommunication fiber is currently the most precise technique available for disseminating frequencies. We summarize some key advances, results and applications for fiber networks spanning up to 1000 km.
{"title":"Frequency dissemination at the 19th decimal place","authors":"G. Grosche, O. Terra, S. Raupach, U. Sterr, H. Schnatz, A. Pape, J. Friebe, M. Riedmann, E. Rasel, S. Droste, K. Predehl, R. Holzwarth, T. Udem","doi":"10.1109/EFTF.2012.6502416","DOIUrl":"https://doi.org/10.1109/EFTF.2012.6502416","url":null,"abstract":"Optical frequency transmission via phase-stabilized telecommunication fiber is currently the most precise technique available for disseminating frequencies. We summarize some key advances, results and applications for fiber networks spanning up to 1000 km.","PeriodicalId":6409,"journal":{"name":"2012 European Frequency and Time Forum","volume":"17 1","pages":"422-423"},"PeriodicalIF":0.0,"publicationDate":"2012-04-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74548446","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 : 2012-04-23DOI: 10.1109/EFTF.2012.6502431
T. Bandi, C. Affolderbach, G. Mileti, C. Calosso, C. Stefanucci, F. Merli, A. Skrivervik
We demonstrate a high-performance laser-pumped rubidium-cell atomic frequency standard exhibiting a short-term stability of < 3×10−13 τ−1/2. The key components of this standard are a Rb vapor cell of 25mm diameter and a newly developed compact microwave resonator cavity. The overall volume of the clock's physics package - including the frequency-stabilized laser head and physics package - is < 3 liters, which shows the potential of this compact clock for future portable applications.
{"title":"Laser-pumped high-performance compact gas-cell Rb standard with < 3×10−13 τ−1/2 stability","authors":"T. Bandi, C. Affolderbach, G. Mileti, C. Calosso, C. Stefanucci, F. Merli, A. Skrivervik","doi":"10.1109/EFTF.2012.6502431","DOIUrl":"https://doi.org/10.1109/EFTF.2012.6502431","url":null,"abstract":"We demonstrate a high-performance laser-pumped rubidium-cell atomic frequency standard exhibiting a short-term stability of < 3×10−13 τ−1/2. The key components of this standard are a Rb vapor cell of 25mm diameter and a newly developed compact microwave resonator cavity. The overall volume of the clock's physics package - including the frequency-stabilized laser head and physics package - is < 3 liters, which shows the potential of this compact clock for future portable applications.","PeriodicalId":6409,"journal":{"name":"2012 European Frequency and Time Forum","volume":"35 1","pages":"494-496"},"PeriodicalIF":0.0,"publicationDate":"2012-04-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74668607","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 : 2012-04-23DOI: 10.1109/EFTF.2012.6502321
M. Goryachev, P. Abbé, S. Galliou
This work presents the results of investigation of frequency sources based on cryogenic BAW quartz resonators. Two systems are considered: a passive feedback frequency stabilisation system and a fully cryogenic oscillator. The first approach improves the long-term frequency stability implementing a minimal number of electronic components at liquid helium temperatures. The second one is a BAW oscillator designed for 4K temperatures based on field-effect and bipolar transistors.
{"title":"Cryogenic quartz frequency sources: Problems and perspectives","authors":"M. Goryachev, P. Abbé, S. Galliou","doi":"10.1109/EFTF.2012.6502321","DOIUrl":"https://doi.org/10.1109/EFTF.2012.6502321","url":null,"abstract":"This work presents the results of investigation of frequency sources based on cryogenic BAW quartz resonators. Two systems are considered: a passive feedback frequency stabilisation system and a fully cryogenic oscillator. The first approach improves the long-term frequency stability implementing a minimal number of electronic components at liquid helium temperatures. The second one is a BAW oscillator designed for 4K temperatures based on field-effect and bipolar transistors.","PeriodicalId":6409,"journal":{"name":"2012 European Frequency and Time Forum","volume":"7 1","pages":"8-13"},"PeriodicalIF":0.0,"publicationDate":"2012-04-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78411767","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 : 2012-04-23DOI: 10.1109/EFTF.2012.6502419
V. Kalinin, J. Beckley, I. Makeev
A new reader is presented that is based on a narrowband pulsed excitation of two SAW resonators contained in a differential wireless resonant sensor such as a torque senor. Simultaneous excitation of the resonators working at 433–437 MHz allows achieving a flat system frequency response up to Nyquist frequency. An interrogation algorithm and a structure of the reader ensure a torque sampling rate of at least 16 kHz and the system bandwidth of at least 8 kHz achievable at the processor clock of 150 MHz. Systematic errors caused by mutual interference of the two SAW responses, intermodulation products and aliasing are discussed. Random errors caused by the phase noise of the local oscillators are analyzed theoretically. Experimental results are also presented.
{"title":"High-speed reader for wireless resonant SAW sensors","authors":"V. Kalinin, J. Beckley, I. Makeev","doi":"10.1109/EFTF.2012.6502419","DOIUrl":"https://doi.org/10.1109/EFTF.2012.6502419","url":null,"abstract":"A new reader is presented that is based on a narrowband pulsed excitation of two SAW resonators contained in a differential wireless resonant sensor such as a torque senor. Simultaneous excitation of the resonators working at 433–437 MHz allows achieving a flat system frequency response up to Nyquist frequency. An interrogation algorithm and a structure of the reader ensure a torque sampling rate of at least 16 kHz and the system bandwidth of at least 8 kHz achievable at the processor clock of 150 MHz. Systematic errors caused by mutual interference of the two SAW responses, intermodulation products and aliasing are discussed. Random errors caused by the phase noise of the local oscillators are analyzed theoretically. Experimental results are also presented.","PeriodicalId":6409,"journal":{"name":"2012 European Frequency and Time Forum","volume":"174 1","pages":"428-435"},"PeriodicalIF":0.0,"publicationDate":"2012-04-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74958271","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 : 2012-04-23DOI: 10.1109/EFTF.2012.6502403
R. Miškinis, D. Smirnov, E. Urba, B. Dzindzelėta
Various characteristics of time transfer over 3G mobile telecommunication networks are investigated. The investigation aims at the three typical regimes in which the modem can be operated: 1) UMTS logical CTCH (Common Traffic Channel) operating over the UMTS FACH (Forward Access Channel) physical channel; 2) UMTS data transfer logical DTCH (Dedicated Traffic Channel) operating over the UMTS DCH (Dedicated Channel) physical channel; 3) HSDPA data transfer logical DTCH (Dedicated Traffic Channel) operating over the HS-DSCH (High Speed Shared Data Channel) physical channel. It is found that the most important role in the quality of synchronization and time transfer is played by the network asymmetry, not the absolute delay time.
{"title":"Improving timing capabilities in 3G mobile networks","authors":"R. Miškinis, D. Smirnov, E. Urba, B. Dzindzelėta","doi":"10.1109/EFTF.2012.6502403","DOIUrl":"https://doi.org/10.1109/EFTF.2012.6502403","url":null,"abstract":"Various characteristics of time transfer over 3G mobile telecommunication networks are investigated. The investigation aims at the three typical regimes in which the modem can be operated: 1) UMTS logical CTCH (Common Traffic Channel) operating over the UMTS FACH (Forward Access Channel) physical channel; 2) UMTS data transfer logical DTCH (Dedicated Traffic Channel) operating over the UMTS DCH (Dedicated Channel) physical channel; 3) HSDPA data transfer logical DTCH (Dedicated Traffic Channel) operating over the HS-DSCH (High Speed Shared Data Channel) physical channel. It is found that the most important role in the quality of synchronization and time transfer is played by the network asymmetry, not the absolute delay time.","PeriodicalId":6409,"journal":{"name":"2012 European Frequency and Time Forum","volume":"10 1","pages":"368-370"},"PeriodicalIF":0.0,"publicationDate":"2012-04-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84387874","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 : 2012-04-23DOI: 10.1109/EFTF.2012.6502405
V. Smotlacha, A. Kuna
This paper describes our experience with long term two-way optical time transfer between Czech and Austrian national time and frequency laboratories maintaining their national time and frequency standards generating the national time scales UTC(TP) and UTC(BEV), respectively. The optical link utilizes either dedicated optical fibers or Dense Wavelength Division Multiplex (DWDM) channels in all-optical production telecommunication networks. Results from the optical transfer, i.e. clock comparison and link delay including diurnal and seasonal effects are shown and also compared with GPS Common-View and Precise Point Positioning.
本文描述了我们在捷克和奥地利国家时间和频率实验室之间进行长期双向光时间传输的经验,这些实验室保持了各自的国家时间和频率标准,分别产生了国家时间尺度UTC(TP)和UTC(BEV)。光链路在全光生产电信网中使用专用光纤或密集波分复用(DWDM)信道。显示了光传输的结果,即时钟比较和链路延迟,包括日和季节影响,并与GPS Common-View和Precise Point Positioning进行了比较。
{"title":"Two-way optical time and frequency transfer between IPE and BEV","authors":"V. Smotlacha, A. Kuna","doi":"10.1109/EFTF.2012.6502405","DOIUrl":"https://doi.org/10.1109/EFTF.2012.6502405","url":null,"abstract":"This paper describes our experience with long term two-way optical time transfer between Czech and Austrian national time and frequency laboratories maintaining their national time and frequency standards generating the national time scales UTC(TP) and UTC(BEV), respectively. The optical link utilizes either dedicated optical fibers or Dense Wavelength Division Multiplex (DWDM) channels in all-optical production telecommunication networks. Results from the optical transfer, i.e. clock comparison and link delay including diurnal and seasonal effects are shown and also compared with GPS Common-View and Precise Point Positioning.","PeriodicalId":6409,"journal":{"name":"2012 European Frequency and Time Forum","volume":"21 1","pages":"375-378"},"PeriodicalIF":0.0,"publicationDate":"2012-04-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85673573","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 : 2012-04-23DOI: 10.1109/EFTF.2012.6502393
E. Şahin, R. Hamid, M. Çelik, C. Birlikseven, G. Ozen, A. Izmailov
We have detected and analyzed narrow, high contrast coherent population trapping (CPT) resonances, which appear in transmission of the probe monochromatic light beam under action of the counter propagating two frequency laser radiation, on example of the nonclosed three level A-system formed by spectral components of the Doppler broadened D2 line of cesium atoms. Given resonances may be used in atomic frequency standards, sensitive magnetometers and in ultrahigh resolution laser spectroscopy of atoms and molecules.
{"title":"CPT resonances in two frequency pumping and probe beam configuration","authors":"E. Şahin, R. Hamid, M. Çelik, C. Birlikseven, G. Ozen, A. Izmailov","doi":"10.1109/EFTF.2012.6502393","DOIUrl":"https://doi.org/10.1109/EFTF.2012.6502393","url":null,"abstract":"We have detected and analyzed narrow, high contrast coherent population trapping (CPT) resonances, which appear in transmission of the probe monochromatic light beam under action of the counter propagating two frequency laser radiation, on example of the nonclosed three level A-system formed by spectral components of the Doppler broadened D2 line of cesium atoms. Given resonances may be used in atomic frequency standards, sensitive magnetometers and in ultrahigh resolution laser spectroscopy of atoms and molecules.","PeriodicalId":6409,"journal":{"name":"2012 European Frequency and Time Forum","volume":"57 1","pages":"323-326"},"PeriodicalIF":0.0,"publicationDate":"2012-04-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80866366","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 : 2012-04-23DOI: 10.1109/EFTF.2012.6502413
M. Čížek, R. Smíd, Z. Buchta, J. Lazar, O. Cíp
The presented work is focused on digital processing of beat note signals from a femtosecond optical frequency comb. The efforts concentrate in two main areas: Firstly, using digital servo-loop techniques for locking free running continuous laser sources on single components of the fs comb spectrum. Secondly, we are experimenting with digital signal processing of the RF beat note spectrum produced by f-2f technique used for assessing the offset and repetition frequencies of the comb, resulting in digital servo-loop stabilization of the fs comb.
{"title":"Digital processing of beat note signals from optical frequency synthesizers","authors":"M. Čížek, R. Smíd, Z. Buchta, J. Lazar, O. Cíp","doi":"10.1109/EFTF.2012.6502413","DOIUrl":"https://doi.org/10.1109/EFTF.2012.6502413","url":null,"abstract":"The presented work is focused on digital processing of beat note signals from a femtosecond optical frequency comb. The efforts concentrate in two main areas: Firstly, using digital servo-loop techniques for locking free running continuous laser sources on single components of the fs comb spectrum. Secondly, we are experimenting with digital signal processing of the RF beat note spectrum produced by f-2f technique used for assessing the offset and repetition frequencies of the comb, resulting in digital servo-loop stabilization of the fs comb.","PeriodicalId":6409,"journal":{"name":"2012 European Frequency and Time Forum","volume":"14 1","pages":"409-411"},"PeriodicalIF":0.0,"publicationDate":"2012-04-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81259062","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}