A1. Time
and Frequency Standards and Time Transfer Technique
In Japan, the researches and
developments on Time and Frequency (T&F) Standards and Time Transfer Technique
are carried out in the National Institute of Information and Communications
Technology (NICT), National
Metrology Institute of Japan (NMIJ), and some Universities.
In April 2004, the
Communications Research Laboratory (CRL) and the Telecommunications Advancement
Organization of Japan (TAO) were merged and reorganized into a new
organization, the National Institute of Information and Communications
Technology (NICT), an incorporated administrative agency. The responsibility of
CRL for the national frequency standard and time dissemination has been
succeeded by NICT.
The accuracy evaluations of
TAI unit by the optically pumped Cs primary frequency standard NICT-O1 have
conducted about twice a year regularly. Papers on the accuracy evaluation of
NICT-O1 were published [Hasegawa et al. 2004, Fukuda et al. 2004]. Development
of Atomic fountain standard in NICT has been in progress. Ramsey fringe has
been obtained with high signal to noise ratio, and the frequency stability of
5x10-13 at the averaging time of 1 second has been achieved [Kumagai
et al. 2002, 2003, 2004 a, b].
Two Way Satellite Time and Frequency
Transfer (TWSTFT) network in the Asia-Pacific region has developed under the
collaboration with NICT and major T&F institutes in the region [Hongwei et
al. 2003a, b]. A multi-channel TWSTFT modem has been developed in NICT [Imae et
al. 2002]. Researches on GPS time transfer have been also conducted [Shibuya et
al. 2002, Sekido et al. 2003, Fujieda et al. 2004a, b, Gotoh et al. 2004b]. On
GPS carrier phase time transfer, precise orbit analysis software “CONCERTO” is
applied to solve the ambiguity problem [Gotoh et al. 2004a].
At the headquarters of
NICT, about 15 cesium atomic clocks with high-performance beam tube have been
operated to generate UTC(NICT). The short term stability of UTC(NICT) has been
also improved by optimizing the control gain of daily frequency adjustment
[Hanado et al. 2002, 2003, 2004a]. A new UTC(NICT) generation system is under
development [Hanado et al. 2004b]. Two standard time and frequency stations
transmit the signals on the LF band [Kurihara et al. 2004]. These signals cover
whole
NICT has developed a
precise time and frequency transfer system for ETS-VIII, a Japanese Engineering
Test Satellite, which will be launched in FY 2005. Using a two-way
time-transfer method and carrier-phase information, this precise time-transfer
system is planned to attain a precision around 10 ps [Takahashi et al. 2002,
Gotoh et al. 2004c]. A plan to develop a regional satellite navigation system
called Quasi-Zenith Satellite System (QZSS) was recently announced. It makes use of three satellites on
inclined orbits separated 120 degrees each other to improve the visibility of
satellites particularly in urban canyons. NICT is to develop time and frequency
technology for this system such as space-borne hydrogen maser atomic clock and
time management system [
Various time and frequency standards
related researches have been conducted in NICT, such as on atomic and molecular
physics [Fukuda et al. 2002 a, b, 2003, 2004 a, b, Kajita 2002a, b, c, d, 2003,
2004a, b, Matsubara et al. 2002, 2003, 2004a, Li et al. 2004], Milli-second
pulsar timing [Hanado et al. 2002, 2003b], Relativistic Effects in time and
frequency standards [Kotake et al. 2002, 2004, Hosokawa et al. 2002, 2004b].
In NMIJ, following researches have
been conducted.
Primary Frequency standards; An atomic fountain frequency standard is under development in NMIJ. The main factor that limits the accuracy of the frequency standard is collisional frequency shift. A simple technique was developed to minimize the collisional frequency shift while keeping the moderate frequency stability. Atoms collected by a magneto-optical trap were cooled to 800nK and launched to 40cm above the microwave cavity giving rise to Ramsey fringes with a linewidth of 0.85Hz. The frequency stability reached to 3-6x10-13 and the uncertainty level is expected to be 1.4x10-15 [Kurosu et al., 2003, Yanagimachi et al., 2004]. Control techniques of laser frequencies were also developed for the applications to cesium standards [Kwon et al., 2003].
Cryogenic Sapphire Oscillator and Low Noise Frequency Synthesis; NMIJ is developing a synthesized microwave local oscillator (LO) for a Cs atomic frequency standard using a cryogenic sapphire oscillator (CSO) under collaboration with the University of Western Australia and BNM-SYRTE [Watabe et al., 2003, Watabe et al., 2004a]. The CSO is a loop oscillator which is servo controlled by a Pound-type frequency stabilization scheme using a phase modulator and a phase corrector. The sapphire-loaded cavity (SLC) was cooled with liquid helium. A Whispering Gallery mode, WGH15,0,0 at 10.812 GHz was chosen because it exhibited the highest Q-factor. The Cs hyperfine transition frequency of 9.192 GHz was synthesized from the 10.812 GHz oscillation frequency. A fractional frequency stability of 6×10-15 was obtained for integration times of 600 to 1200 s. At the integration times shorter than 300 s the result was limited by the H-maser. The stability is clearly superior to the hydrogen maser at short integration times and it is expected to be well below 10-14 for 1 s ≤ τ ≤ 100 s [Watabe et al., 2004b].
Time Keeping and Time Comparison; In NMIJ, four cesium atomic clocks with high-performance beam tubes (Agilent 5071A) are operated for time keeping. One of them (Clock code and number 35 224 in BIPM report) was referred as UTC(NMIJ) before June 3, 2004(MJD= 53159). Since then, an AOG (Auxiliary Output Generator) has been used for steering UTC(NMIJ) much closer to UTC. The source clock for the AOG will be replaced by a hydrogen maser frequency standard to improve the short term stability in 2005 and the ensemble clock method will be introduced to improve the long term stability and reliability in 2006. For the contribution to the TAI, two types of GPS receivers, AOA TTR 6 (single-channel common-view method) and Ashtech Z12-T (Multi-channel carrier phase method) have been used. TWSTFT between NMIJ and NICT is continued to realize precise time comparison in the order of 10-15. An optical fiber bidirectional time transfer system using Wavelength Division Multiplexing technology is investigated in NMIJ as future precise time and frequency comparison technique [Amemiya et al., 2004].
Frequency Calibration Services; A frequency remote calibration system is under development in NMIJ.
A common-view experiment was carried out between Tsukuba and
In Kinki-University and
A2. Laser Stabilization and
Frequency Measurement
After an advent of an “optical frequency comb” technology at the end of the last millennium, which is introduced by Prof. Haensch group at MPQ in Garching and Prof. Hall group at JILA in Boulder, a direct comparison between microwave and optical frequencies has been realized by using an one-octave optical frequency comb generated by self-phase modulation in a photonic-crystal fiber. Since 2000, NMIJ also has started a project to realize a direct comparison between microwave and optical frequencies by using several types of ultra-fast mode-locked lasers.
Thanks to this breakthrough, the concept of an
optical frequency standard using such as single trapped ions or ultracold
neutral atoms in free fall, which are aiming to realize the SI second or
frequency standard at an optical region, has become much more feasible. Prof.
Katori (
NICT is developing a single Ca+ ion
trap standard. A trap with laser cooling system is completed and some
theoretical investigations are made [Matsubara et al. 2004b, Kajita et al.
2004c]. To observe the 4s2S1/2 - 3d2D5/2 forbidden transition (729 nm), a
narrow linewidth laser is being developed. So far, a few tens Hz linewidth and
the stability of 10-13 for the laser is achieved [Li et al. 2004].
NMIJ has been developing several stabilized
lasers and optical frequency measurement systems by means of optical frequency
combs generated from ultra-fast mode-locked Ti:Al2O3 (TiS)
lasers and mode-locked fiber lasers. NMIJ has measured optical frequencies of
several stabilized lasers by the frequency measurement systems and has reported
results on an acetylene stabilized laser at 1542 nm [F.- L. Hong et al.,
2003a], an iodine stabilized Nd:YAG lasers at 532 nm [F.- L. Hong et al.,
2003b, 2004a, b] and a new optical standard at 660 nm and 1319 nm for optical
telecommunication [R. Guo et al., 2004] at the working group of mise en
pratique (MeP) in the Consultative Committee for Length (CCL) of the meter
convention which was held at the BIPM (Bureau international des poids et
mesures) in 2003.
To realize an optical frequency standard, it is
very essential that an optical frequency comb can link microwave and optical
frequencies for a day or a week to evaluate its accuracy referring to the SI
second. As one of promising candidates for that purpose, a mode-locked fiber
laser provides a very robust frequency comb and a frequency measurement system.
NMIJ has developed frequency combs based on mode-locked fiber lasers [Hong et
al., 2003c, Schibli et al., 2004]. The stability degradation of a mode-locked
Ti:sapphire laser has been studied through phase noise measurement [Inaba et
al., 2005]. The frequency measurement system combined with a sum frequency
generation comb and a broadened comb by a photonic crystal fiber has been
developed. In this system we need not to stabilized the CEO frequency, which
makes the system robust for a long term operation.[Jiang et al., 2005]. Phase
locking of a continuous-wave optical parametric oscillator to an optical
frequency comb have been demonstrated as the first step for optical frequency
synthesis [Inaba et al., 2004].
Prof. Tkahashi et al. (
A3. Realization
of Electrical Units ( DC & LF)
Based on Josephson voltage standard and Quantum
Hall resistance (QHR) standard maintained as national standards, electrical
standard division of National Metrology Institute of Japan (NMIJ) has been
focused on to establish practical standards such as impedance standards in
low-frequency and other standards in this term corresponding to urgent
requirements from industry.
Effects of environmental conditions of four
Zener voltage references units have been investigated in detail for using
traveling standards of Japanese standard dissemination system [Nishinaka, H.,
et al., 2002-2003].
A voltage divider has developed in NMIJ to
calibrate up to 1 kV. The ratio of the divider can be automatically
self-calibrated in 1000 V/ 10 V and 100 V/ 10 V and participated to the
international comparison [Sakamoto, Y., 2002-2004].
Resistance standards and Terra-ohm meter in the
range from 1 MΩ to 1 TΩ in decade steps have
been developed by using Cryo Current comparator (CCC) and resistance-bridge
based on the QHR standard [Kiryu, S. et al., 2002-2004].
The capacitance standard derived from a DC
resistance corrected by the QHR standard into ac-dc calculable-resistor, which
is further converted to static capacity by means of a multi-frequency
quadrature-bridge enables the measurement of the frequency dependence of the
capacitor [Nakamura, Y. et al., 2001-2004].
We have expanded capacitance standard from small
range [10 pF, 100 pF, and 1000 pF at 1 kHz] and [10 pF, 100 pF, and 1000 pF at 1.592
kHz] to medium range [0.01μF, 0.1μF, 1μF
at 1 kHz] and [0.01μF, 0.1μF, 1μF
at 1 kHz at 1.592 kHz] by using a capacitance-bridge system.
Several kind of Induced Voltage Divider (IVD) in
the range of [0.1~1.0, 10 V at 1 kHz], [0.1~1.0, 100 V at 1 kHz], and [0.1~1.0,
10 V at 200 Hz and 400 Hz] have been developed in order to establish those
capacitance standards [Nakamura, Y. et al., 2001-2004]. AC resistance standard
(ac-dc calculable resistor) [10 k at 1 kHz] also has been developed for
establishing capacitance standard [Nakamura, Y. et al., 2004].
Inductance standards in the range of [10 mH at 1
kHz], [10 mH and 1.592 kHz], and [100 mH at 1 kHz] have been developed based on
the simple inductance measurement method using a commercial LCR meter
[Yonenaga, A. et al., 2003-2004].
AC/DC difference standard in the range of [2-20
V, 10 mA at 10 Hz to 1 MHz] and [20-1000 V at 10 Hz to 100 kHz] based on TCs
(thermal converters) have been developed
by using fast-reversed
dc (FRDC) method [Fujiki, H. et al., 2001-2003].
AC current comparator in the range of [50 A,
1/1-1/100 at 45 to 65 Hz], and [50 A, 1/1-1/100 below 120 Hz] have been
developed in order to establishing AC power standard [Yamada, T. et al., 2003].
A4. EM Field, Power
Density and Antenna Measurement
In the field of precision measurements like
EMC/EMI, a dipole antenna is used as a primary standard for wire antennas. The
simplest structure enables us to evaluate its characteristics by some numerical
methods and further a good agreement is obtained in the comparison between the
numerical and measured results. In the frequency range from 30 to 1000 MHz,
antenna factor (AF) is a popular parameter to indicate the antenna sensitivity to
incident electric field. The measurement of the AF is usually carried out on an
open-area test site (OATS), though it has height-dependency on a ground plane
due to the coupling between the antenna and the ground-plane. The uncertainty
associated with the dipole antenna calibration in NMIJ at 2.0 m high above the
ground plane with horizontal polarization is reported in [Komiyama 2004].
However, in the method the accurate
field-strength is not be realized namely by measurements. The field-strength is
assumed as in the free-space condition. Therefore the uncertainty of the AF
measurement will significantly increase at the condition of small electric
field. To overcome the problem two approaches are proposed. One is to obtain
the AF at an arbitrary height by a single site attenuation measurement [Morioka
et al. 2004]. This is a kind of standard field method, but no field-strength
should be explicitly evaluated instead of introducing a coefficient as a
substitution.
The other approach is to adopt a free-space
measurement. Nowadays, the measurement in a full anechoic chamber becomes
common. Thus the field-strength measurements require free-space AF in the free
space. [Matsumoto et al, 2003] proposed a method to obtain free-space AF by
scanning an antenna above the absorber-attached OATS. As the input impedance of
the antenna is affected by the mutual coupling with its image, this effect can
be removed by using numerical method. A method proposed in [Fujii et al. 2004]
also provides free-space AF by using the measured input impedance.
The complex antenna factor (CAF) of a dipole
antenna with a balun can be determined from the effective length and the input
impedance of the antenna element and the S-parameters of the balun. The
effective length and the input impedance are calculated by a numerical method
such as the method of moments. The S-parameters are measured using a network
analyzer with its TRL calibration. Alternatively, the CAF can be determined by
a modified three-antenna method on a ground plane. In the present paper, the
systematic uncertainties of the two methods are estimated in the frequency
range of 30 - 1000 MHz in order to clarify the potential for application of the
two methods and to determine areas for improvement. The CAF values determined
by these two methods are compared, and the results of this comparison indicate
the validity of the uncertainty estimations. In the measured balun method, the
TRL measurement should be improved in the low-frequency range (30-100 MHz), and
in the three-antenna method, the antenna positioning should be improved [Iwasaki
et al. 2004a].
A continuous antenna factor in a wide frequency
range is convenient to be used and such a broad-band antenna as a log-periodic
antenna was evaluated for a metrology standard. A new method was proposed for
evaluating a free-space antenna factor continuously through a wide frequency
band. The method is based on a technique of a time-domain analysis and a
pulse-compression technology for reducing the influence by the reflected waves
from surrounding obstacles [Kurokawa et al. 2003]. The method was examined for
calculating the free-space antenna factor of a log-periodic antenna widely used
for EMI measurement [Kurokawa et al. 2004].
The development of calibration techniques for
standard loop antennas was carrying out by ETL and CRL in these 30-40 years.
Recently both of these organizations changed to AIST and NICT, respectively.
The AIST started to develop the calibration method again since 2002. Basically
the methods depend on “3-Antenna technique” [Ishii et al. 2003] and “Reference
Antenna Method”. They are also studying another new calibration method
“Measuring Impedance Method [Ishii et al. 2004]”. They are taking part in the
International Comparison in 2002-(in progress) and started a calibration
service for small loop antennas from 2005 as a member of NMI’s.
On the other hand, NICT and
There appeared a new technique to measure
standard horn antennas. The technique was combined with a photonic sensor and
several near-field measurement techniques, where the photonic sensor was used
as a probe that is small, light-weight and broad-band (below about 10 GHz). The
technique was also used to measure other antennas such as micro-strip antennas
and the log-periodic antennas. Since these were prototypes, there was about 1
dB difference between the results by the technique and by conventional antennas
and methods. The technique is
promising to measure various standard antennas without the influences by metal
probe and metal cables in the field of metrology. [Hirose et al. 2002, Hirose
et al. 2003a, Hirose et al. 2003b, Hirose et al. 2004a, Hirose et al. 2004b,
Hirose et al. 2004c, Hirose et al. 2004d]
A novel method for measuring microwave
reflection coefficients without the open and load standards is proposed. In
this method, a single probe is inserted into an air line and the output wave is
detected by a vector detector. Offset shorts are used for the calibration. The measurement
system is constructed using 7 mm coaxial line and APC7 connectors. The result
of the measurement in the frequency range 1 - 9 GHz shows the possibility of
the proposed method. All the major systematic errors can be estimated from the
data that is easily obtainable [Iwasaki et al. 2004b].
To observe transient radiation fields, a
technique for reconstructing electromagnetic (EM) waveforms using the complex
antenna factor (CAF) have been developed. However, the CAF is originally
defined assuming plane wave incidence, while the waveforms are measured in a
vicinity of the radiating source. In order to examine the reconstruction
technique using the CAF in the near-field measurements, the EM fields radiated
from a monopole antenna excited by pulsed input voltage was reconstructed and
compared with calculated results. For the geometry of the experiment, the
waveforms of the reconstructed and calculated EM fields have shown good
agreement. Therefore, the reconstruction technique using the CAF can be used
for similar dimensions or at a greater distance when sufficient sensitivity is
provided [Hamada et al. 2002].
A5. Power, Attenuation
and Impedance Measurement
In the year 2000, a new national standard
infrastructure plan for attenuation was mapped out at NMIJ to meet the
increasingly growing demands for accurate, traceable, and broad-band standards
which have a high attenuation range. The measurement capability was planned to
cover the frequency range of 10 MHz to110 GHz and the attenuation range of
greater than 50 dB. The first developed measurement system was for an
attenuation standard from 10 to 100 MHz [Widarta et al. 2002a, 2003a]. The system uses an inductive voltage
divider (IVD) operating at 1 kHz as a reference standard and employs
dual-channel intermediate frequency (IF) substitution method. The IVD is used
for direct traceability of the
Based on the developed system’s design, a
broadband attenuation measurement system working in the frequency range of 10
MHz to 18 GHz was also successfully developed [Widarta et al. 2002b, 2003b,
2004a]. Some unique techniques such as usages of interpolation technique,
double step measurement technique, etc., were introduced in order to improve
the uncertainties. The system is used as a national standard of attenuation and
provides the attenuation calibration to several service systems including Japan
Calibration Service System (JCSS). The calibration and measurement capabilities
are up to 100 dB in frequency range of 100 MHz to 12 GHz, and up to 60 dB at 18
GHz. Enhancing to the frequency range up to 40 GHz is being developed now.
A study on analysis of the
linearity of heterodyne detection and an important property in applying the IF
substitution method in attenuation measurements, is carried out and the results
show that the linearity check by the dependence of measured attenuation on
measuring levels is mostly reasonable [Kawakami et al. 2004].
Implementing optical fiber
assemblies was proposed to obtain extremely high isolation between the channels
of dual channel measurement system in RF and microwave frequency range [Widarta
et al. 2002c, 2003c]. The isolation effects were demonstrated in attenuation
measurement systems and satisfactory results were shown. The assemblies also
gave good flexibility to the structure of the system and minimized earth loop
problems.
As for the noise standard,
National Meteorology Institute of Japan (NMIJ) has developed a new microwave
radiometer system for the measurement of noise sources with PC7 coaxial output
connector in the frequency range from 2 GHz to 18 GHz. It is a type of total-power radiometer
which employs a null-balanced method in order to reduce an instability and
non-linearity [Nakano et al. 2002a].
NMIJ has been also
developing the original cryogenic standard noise source with PC7 coaxial
connector by using the auxiliary transmission line method which is cooled by
liquid nitrogen. The measured value
of the noise temperature of the original noise source is good agreement with
the noise temperature which is calculated by the loss measurement of each
auxiliary transmission line [Nakano et al. 2002b, 2003].
A survey on precision thermal
noise power measurement techniques in RF region and the thermal noise standards
established in the leading national metrology institutes are reviewed by
NMIJ. The noise temperature
measurement system developed by NMIJ is also described. Performance of the measuring instrument
of noise temperature is evaluated to verify the measurement system. The uncertainty of the noise measurement
system is discussed by the radiometer equation [Shimada 2003].
NMIJ has established the
calibration system of the noise temperature for the coaxial noise sources with
PC7 and PC3.5 coaxial output connectors.
The noise temperature calibration systems and the uncertainty analysis
of the calibration of coaxial noise sources are reviewed [Shimada 2004].
References
Amemiya, M., M. Imae, Y. Fukuyama, Y.
Shibuya, T. Ikegami, and
Domae, A., Y. Nakamura, and Y. Ichikawa
[2004], "Calibration of standard capacitors of 0.01 - 1 micro-F at
NMIJ/AIST", CPEM ’04 Conference Digest, pp.608-609
Fujieda,
M., M. Imae, Y. Sibuya [2004a], “Effects of ionospheric correction on GPS time
transfer throughout
Fujieda,
M. Imae, Y. Sibuya [2004b], “GPS C/A-code time-transfer stability in
Fujii,
K., S. Kaketa, A. Sugiura, Y. Matsumoto and Y. Yamanaka [2004], “Calibration of
EMI antennas in the VHF band with antenna impedance measurements,” Proceedings
of the International Conference on EMC 2004, pp. 361-364.
Fujiki, H., A. Domae and Y. Nakamura
[2002], "Analysis of the time
constant for the bifilar calculable ac/dc resistors", CPEM Digest,
pp.344-345, 2002.
Fujiki, H., A. Domae and Y. Nakamura [2003], "Analysis of Time Constant of
Calculable AC/DC Resistors for the Phase Angle Standard ", JJAP, vol 42,
pp.5357-5360, 2003.
Fujiki, H., K. Kasai , H. Sasaki, A. Shoji,
S. Nakano, N, Nishiya and S. Hidaka [2004], “High-Performance Thin Film Multijyunction
Thermal Converter Developed at AIST”, CPEM Digest, pp.459-460, 2004.
Fukuda,
K., A. Hasegawa, T. Kobayashi, Y. Yoshino, T. Suzuki, M. Hosokawa, M. Tachikawa
[2002a], “Temporal variation of local density of Cs atoms in MOT,” Proc.
EFTF2002, pp.E-053-E-055
Fukuda,
K., M. Kinoshita, A. Hasegawa, M. Hosokawa, M. Tachikawa [2002b], “Compact
frequency standard using EIT signal of Cs atoms in a thin cell,” Proc. ATF2002,
pp.116-119
Fukuda,
K., M. Kinoshita, M. Tachikawa [2003], “Allan-variance measurements of diode
laser frequency stabilization with a thin vapor cell,” Appl. Phys. B
Fukuda,
K., A. Hasegawa, H. Ito, M. Kumagai, N. Kotake, M. Kajita, M. Hosokawa, T.
Morikawa [2004a], “Optically pumped cesium primary frequency standard,” Journal
of the NICT, vol.50, no.1/2, pp.39-49
Fukuda, K., M.
Kinoshita, A. Hasegawa, M. Tachikawa, M. Hosokawa [2004b], “Compact clocks
using a thin cesium cell,” Journal of the NICT, vol.50, no.1/2, pp.95-103
Gotoh, T., T.Otsubo, T.
Kubooka, M. Imae, M. Fujieda [2004a], “GPS common-vew with geodetic receivers,”
Proc. EFTF2004
Gotoh, T., A. Kanako,
Y. Sibuya, M. Imae [2004b], “GPS common view,” Journal of the NICT, vol.50,
no.1/2, pp.113-123
Gotoh, T., M. Hosokawa, F. Nakagawa, Y. Takahashi, M. Fujieda, M. Imae, H. kiuchi, M. Aida, Y. Guo, R., F. -L. Hong, A. Onae, Z. -Y. Bi, H. Matsumoto, K. Nakagawa [2004], “Frequency stabilization of a 1319-nm Nd:YAG laser by saturation spectroscopy of molecular iodine”, Opt. Lett., vol. 29, no. 15, pp. 1733-1735.
Takahashi [2004c], “Time
comparison equipment for ETS-VIII satellite-part 2 plans of precise time
transfer experiment-,” Journal of the NICT, vol.50, no.1/2, pp.145-153
Gotoh, T., T.Otsubo, T.
Kubooka [2004d], Influence of tropospheric delay correction models on GPS
carrier phase time transfer, ATF2004, pp.280-284
Hamada, L.,
Hanado, Y., M. Imae, M.
Aida, M. Hosokawa, N. Kurihara [2002a], “Present and Future of UTC(CRL)
Generation System,” IV International Time Scale Algorithm Symposium,
Hanado, Y., Y. Shibuya,
M. Hosokawa, M. Sekido, T. Gotoh, M. Imae [2002b], “Timing observation of
millisecond pulsar PSR1937+21 using the Kashima 34-antenna,” Publ. Astron. Soc.
Japan, vol.54, pp.305-313
Hanado, Y., M. Imae, Y.
Sibuya [2002d], “Upgrading of the frequency stability of UTC(CRL),” Proc.
ATF2002, pp. 192-198
Hanado, Y., K. Imamura,
M. Imae [2003a], “Upgrading of UTC(CRL) ,” Proc. IEEE FCS & EFTF2003
Hanado, Y., Y. Sibuya,
F. Nakagawa, M. Sekido, M. Hosokawa, M. Imae [2003b], “Timing observation of
PSR1937+21 at CRL,” 25th General Assembly of the IAU
Hanado, Y., M. Imae, M.
Aida, M. Hosokawa, H. Ito, F. Nakagawa, Y. Shimizu [2004a], “Algorithm of
ensemble atomic time,” Journal of the NICT, vol.50, no.2/1, pp.155-167
Hanado, Y., M. Imae, N.
Kurihara, M. Hosokawa, M. Aida, K. Imamura, N. Kotake, H. Ito, T. Suzuyama, F.
Nakagawa, Y. Shimizu[2004b], “Generating and measurement system for Japan
standard time”, Journal of the NICT, vol.50, no.1/2, pp.169-177
Hanaoka,
K., S. Matsuzawa, K. Kudou, H. Maruyama, Y. Ito, and Y. Sakamoto [2004],
"Dc voltage ratio self-calibration by build-up method using
reference voltages of 10 V and 100 V", IEEJ Trans, FM, vol. 124, no. 3,
pp. 236-242.
Hasegawa,
A., K. Fukuda, M. Kajita, H. Ito, M. Kumagai [2004a], “Accuracy evalution of
optically pumped primary frequency standard CRL-01,” Metrologia , vol.41, no.4,
pp.257-263
Hayashi
S, and M. Tachikawa, “Laser Guidance of Cs Atoms through Hollow-Core Optical
Fiber,” Proceedings of ATF 2002, pp. 326-399.
Hirose,
H, K. Komiyama, J. Ichijo and S. Torihata [2002],”
Pattern measurement of X-Band standard gain horn antenna using photonic sensor
and planar near field scanning technique,” Proc. AMTA 2002, pp. 284-288.
Hirose,
H, T. Ishizone, J. Ichijo,
Hirose,
H, K. Komiyama and T. Ishizone [2003b],”Antenna pattern measurement of
microstrip antenna using photonic sensor and spherical scanning technique,”
Proc. AMTA 2003, pp. 461-464.
Hirose,
H, T. Ishizone and K. Komiyama [2004a],”Antenna
pattern measurements using photonic sensor for planar near-nield measurements
at X Band,” IEICE Trans. Commun, vol.E87B, no.3, pp. 727-734.
Hirose,
H, K. Komiyama and T. Ishizone [2004b],” Antenna
pattern comparison of a microstrip antenna on a finite substrate using
near-field measurement and FEKO,” Proc. ACES 2004, no.904162, pp. 1-4.
Hirose,
H, K. Komiyama and T. Ishizone [2004c],” Antenna
Pattern Measurement Using Photonic Sensor and Near-Field Scanning Techniques,”
2004 CPEM Digest, vol.1, pp. 78-79.
Hirose,
H, S. Kurokawa, K. Komiyama and T. Ishizone [2004d],” 3D pattern measurement of Log-preriodic dipole antenna using photonic
sensor and spherical near-field scanning below 2 GHz,” Proc. ISAP 2004, vol.2,
pp. 1017-1020.
Hong,
F. –L., M. Takamoto, R. Higashi, Y. Fukuyama, J. Jiang, H. Katori [2005],
“Frequency measurement of a Sr lattice clock using an SI-second- referenced
optical frequency comb linked by a global positioning system (GPS)”, Opt. Exp.,
vol. 13 no. 14, pp. 5253-5262.
Hong,
F. -L., A. Onae, J. Jiang, R. Guo, H. Inaba, K. Minoshima, T. R. Schibli, H.
Matsumoto [2003a], “Absolute Frequency Measurement of an Acetylene- Stabilized
Laser at 1542 nm” Opt. Lett., vol. 28, No. 23, pp. 2324-2326.
Hong,
F. -L., J. Ishikawa, K. Sugiyama, A. Onae, H. Matsumoto, J. Ye, J. L. Hall
[2003b], “Comparison of Independent Optical Frequency Measurements Using a
Portable Iodine-Stabilized Nd:YAG Laser”, IEEE trans., vol. IM52, No. 2, pp.
240-244.
Hong,
F. -L., K. Minoshima, A. Onae, H. Inaba, H. Takada, A. Hirai, H. Matsumoto, T.
Sugiura, M. Yoshida [2003c], “Broad-spectrum frequency comb generation and
carrier-envelope offset frequency measurement by second-harmonic generation of
a mode-locked fiber laser”, Opt. Lett., vol. 28, no. 17, pp. 1516-1518.
Hong,
F. -L., J. Ishikawa, Y. Zhang, R. Guo, A. Onae, H. Matsumoto [2004a],
“Frequency reproducibility of an iodine-stabilized Nd:YAG laser at 532 nm”,
Opt. Commun. vol. 235, pp. 377-385.
Hong,
F. -L., S. Diddams, R. Guo, Z.- Y. Bi, A. Onae, H. Inaba, J. Ishikawa, K.
Okumura, D. Katsuragi, J. Hirata, T. Shimizu, T. Kurosu, Y. Koga, H. Matsumoto
[2004b], ”Frequency measurements and hyperfine structure of the R(85)33-0
transition of molecular iodine with a femtosecond optical comb”, J. Opt. Soc.
Am. B, vol. 21, no. 1, pp. 88-95.
Hongwei,
S., M. Imae, T. Gotoh [2003a], “Impact of satellite motion on two-way satellite
time and frequency transfer,” Electron. Lett., vol.39, no.5, pp.482-483
Hongwei,
S., M. Imae, T. Gotoh [2003b], “Performance of two-way satellite time and
frequency transfer in Asia-Pacific region,” J. Geodetic Soc.
Hosokawa,
M., David Jauncey, John Reynoldｓ, A. Tzioumis, K. Onishi, T. Fukushima [2002], “Possible
fluctuation of the position of sagittarius A＊ relative to extragaractic radio sources,” Astrophys. J.,
vol.580, pp.L43-L46
Imae,
M., T. Gotoh,T . Suzuyama, Y.
Sibuya, F. Nakagawa, R. Tabuchi [2002], “Time transfer modem for TWSTFT
developed by CRL ,” Proc. ATF2002, pp. 210-217
Imamura,
K., T. Gotoh, A. Kanako, M. Imae,
Inaba,
H., T. Ikegami, F. -L. Hong, A. Onae, Y. Koga, T. Schibli, K. Minoshima, H.
Matsumoto, S. Yanadori, O Tohyama, S. Yamaguchi [2004], “Phase Locking of a
Continuous-Wave Optical Parametric Oscillator to an Optical Frequency Comb for
Optical Frequency Synthesis”, IEEE vol. QE 40, no. 7, pp.929-936.
Inaba,
H., S. Yanagimachi, F. -L. Hong, A. Onae, Y. Koga, H. Matsumoto [2005],
“Stability Degradation Factors Evaluated by Phase Noise Measurement in an
Optical-Microwave Frequency Link Using an Optical Frequency Comb”, IEEE trans.,
vol. IM54, no. 2, pp. 763-766.
Ishida,
H., J. Araki [2004], “Design and analysis of UWB bandpass filter with ring
filter,” IEEE Microwave Theory and Techniques , vol.2004IEEE, pp.1307-1310
Ishii,
M. and K. Komiyama, [2003], “A Measurement Method for Magnetic Antenna Factor
of Small Circular
Ishii,
M., K. Komiyama, [2004], “A Measurement
Method for the Antenna Factor of Small
Ito,
H., M. Hosokawa, J. Umezu, T. Morikawa, K. Takahei, M. Uehara, K. Mori, M.
Tsuda [2002], “Development and preliminary performance evaluation of a
spacebone hydrogen maser,” Proc. ATF2002, pp.103-109
Ito,
H., M. Hosokawa, J. Umezu, T. Morikawa, M. Tsuda, K. Takahei, M. Uehara, K.
Mori [2004], “Hydrogen maser,” Journal of the NICT, vol.50, no.1/2, pp.85-94
Iwama,
T., M. Imae, N. Kurihara, A. Otsuka, H. Usui, N. Kotake[2002],
“Frequency-standards calibration system certificated with ISO17025 in CRL,”
Proc. ATF2002, pp.269-272
Iwama,
T., N. Kurihara, M. Imae, T. Suzuyama, N. Kotake, A. Otsuka [2004b], “Frequency
standards calibration system and remote,” Journal of the NICT, vol.50, no.1/2,
pp.195-203
Iwama,
T., N. Kurihara, M. Imae, K. Imamura, N. Kotake, T. Gotoh, T. Suzuyama, T.
Morikawa [2004], “Development of the trusted time stamping system,” Journal of
the NICT, vol.50, no.1/2, pp.205-209
Iwasaki,
T., and K. Tomizawa [2004a],"Systematic uncertainties of the complex
antenna factor of a dipole antenna as determined by two methods," IEEE
Trans. on Electromagnetic Compatibility, Vol.46, No.2, pp. 234-245.
Iwasaki,
T., and M. Takashima [2004b], "Single probe method with vector detection
for measuring microwave reflection coefficient," IEICE Trans. on
Electronics," Vol.E87-C, No.5, pp. 665-671.
Izmailov,
A, k. Fukuda, M. Kinoshita, M. Tachikawa, [2004], “On sub-Doppler absorption
resonances based on optical pumping and transit of atoms in a thin cell,” Laser
Phys., vol.14, no.1, pp.30-38
Jiang,
J., A. Onae, H. Matsumoto, F. -L. Hong [2005], “ Frequency measurement of
acetylene-stabilized lasers using a femtosecond optical comb without
carrier-envelope offset frequency control”, Opt. Exp., vol. 13, no. 6, pp.
1958-1965.
Kajita,
M., T. Suzuki, H. Odashima, Y. Moriwaki, M. Tachikawa [2001], “Dynamic
properties of polar molecules confined in electrostatic trap ,” Japan J. Appl.
Phys. II, vol.40, no.11B, pp.L1260-L1263
Kajita,
M. [2002a], “Molecular deceleration in a ring electrode,” Proc. EFTF2002,
pp.E067-E070
Kajita,
M. [2002b], “Collisions between electrostatically confined linear polar
molecules,” Euro. Phys. J. D , vol.20, no.1, pp.55-59
Kajita,
M. [2002c], “Molecular trapping and deceleration using a ring electrode,” Japan
J. Appl. Phys., vol.41, no.11A, pp.6577-6581
Kajita,
M. [2002d], “Collisions between electrostatically trapped molecules,” Proc.
ATF2002, pp.179-184
Kajita,
M. [2003], “Cold collisions between linear polar molecules,” Euro. Phys. J. D ,
vol.23, pp.337-342
Kajita,
M. [2004a], “Cold collisions between Boson or Fermion molecules,” Phys.
Rev. A, vol.69, no.12709, pp.1-8
Kajita,
M. [2004b], “The improvement of frequency stability using the collimation
apparatus of the launched atomic fountain,” Journal of the NICT, vol.50,
no.1/2, pp.69-74
Kajita,
M., K. Matsubara, Y. Li, K. Hayasaka, M. Hosokawa [2004c], “Preparing single
ions in m=0 states in the Lamb-Dicke regime,” Japan J. Appl. Phys., vol.43,
no.6A, pp.3592-3595
Kajita,
M. [2004d], “Collisions between molecules in the J=O state,” Euro. Phys. J. D ,
vol.31, no.1, pp.39-43
Katori,
H., [2002] “SPECTROSCOPY OF STRONTIUM ATOMS IN THE LAMB-DICKE CONFINEMENT”,
Proc. 6th Symp. on Frequency Standards and Metrology (ed. Gill, P.),
pp. 323-330, (World Scientific, Singapore 2002).
Katori,
H., M. Takamoto, V. G. Pal’chikov, V. D. Ovsiannikov [2003], “Ultrastable
optical clock with neutral atoms in an engineered light shift trap”, Phys. Rev.
Lett., vol. 91, 173005.
Kawakami,
T., A. Widarta and K. Komiyama [2004], “A consideration of linearity in
heterodyne detection,” 2004 CPEM，Th4c43，pp.626-627.
Kimura,
K. [2004a], “Satellite collision avoidance in quasi-zenith satellite
constellation with orbit intersections at hand-over points,” ISTS,
vol.ISTS204-, no.f-17, pp.1-6
Kimura,
K. [2004b], “Elevation properties of a quasi-zenith satellite system using
circular orbits,” IEICE Trans. Commun., vol.E87-B, no.8, pp.2142-2151
Koike,
K., H. Masuzawa, I. Nishiyama, M. Sakasai, T. Shinozuka, F. Tsukada, [2002],
“Uncertainty of magnetic field intensity with loop antenna calibration system.”
International Conference on Electromagnetic Compatibility (ICEMC), .
Komiyama,
K. [2004], “Development and traceability of metrological standards on radio
frequency and EM field in NMIJ,” Proceedings of the International Conference on
EMC 2004, pp. 373-376.
Komori,
K., Y. Takasu, M. Kumakura, Y. Takahasi, T. Yabuzaki [2003], “Injection-Locking
of Blue Laser Diodes and Its Application to the Laser Cooling of Neutral
Ytterbium Atoms”, Jpn. J. Appl. Phys., vol. 42, pp. 5059-5062.
Kotake,
N., Y. Shimizu, M. Hosokawa,
Kotake,
N., Y. Shimizu, K. Imamura, A. Kanako, N. Kurihara, M. Hosokawa [2004], “The
detection of gravitational red shift by transportation of atomic clocks,”
Journal of the NICT, vol.50, no.2/1, pp.211-219
Kumagai,
M., H. Ito, K. Fukuda, M. Kajita, M. Hosokawa, T. Morikawa [2002], “Development
of Cs atomic fountain frequency standard at CRL,” Proc. ATF2002, pp.150-155
Kumagai,
M., H. Ito, K. Fukuda, M. Kajita, M. Hosokawa, T. Morikawa [2003], “Development
of a Cs atomic fountain frequency standard at CRL,” Proc. IEEE FCS &
EFTF2003, no.P74
Kumagai,
M., H. Ito, K. Fukuda, M. Kajita, M. Hosokawa, T. Morikawa [2004a], “Recent
process on Cs atomic fontain at NICT,” Proc. EFTF2004
Kumagai,
M., H. Ito, K. Fukuda, M. Kajita, M. Hosokawa, T. Morikawa [2004b], “Development
of atomic fountain primary frequency standard at CRL,” Journal of the NICT,
vol.50, no.1/2, pp.51-67
Kurihara,
N. [2004],”JJY, the national
standard on time and frequency in
Kurokawa,
S., T. Sato, [2003] “A design scheme for electromagnetic shielding clothes via
numerical computation and time domain measurement,” IEICE Trans. Electron.,
vol.E86-C, no. 11.
Kurokawa,
S., K. Komiyama, T. Sato, [2004], “Experimental Study of Antenna Factor
Measurement for Logperiodic Antenna with the Time Domain Method,” Proceeding of
CPEM2004, Tu4c23, pp.196-197.
Kurosu
T., Y.
Kwon,
T. Y., T. Kurosu, Y. Koga,
Li,
Y., T. Ido, T. Eichler, H. Katori [2004], “Narrow-line diode laser system for
laser cooling of strontium atoms on the intercombination transition,” Appl.
Phys. B, vol.78, pp.315-320
Li,
Y., H. Ito, K. Matsubara, K. Fukuda, M. Kajita, M. Hosokawa [2004b], Frequency
tunable diode laser system for the S-D transition of Ca+ Ion, ATF2004,
pp.183-189
Marullo-Reedtz, G., R. Cerri,
Matsubara,
K.,
Matsubara,
K., U. Tanaka, H. Imajo,
Matsubara,
K., S. Urabe, M. Watanabe [2004a], “Precise frequency measurement using trapped
zinc ions,” Journal of the NICT, vol.50, no.1/2, pp.71-84
Matsubara,
K., K. Toyoda, Y. Li, U. Tanaka, S. Uetake, K. Hayasaka, S. Urabe, M. Hosokawa
[2004b], Fundamental study for a 43Ca+ optical frequency standard, CPEM2004,
pp.430-431
Matsumoto,
Y., T. Umeda, A. Nishikata, K. Fujii, Y. Yamanaka and A. Sugiura [2003], “EMI
antenna calibration on an absorber-lined ground plane to determine free-space
antenna factor,” IEEE Trans. on EMC, vol. 45, no. 4, pp. 656-660.
Morikawa,
T. [2004], “Definitions of time and frequency standard,” Journal of the NICT,
vol.50, no.1/2, pp.3-6
Musha,
M., A. Ueda, M. Horikoshi, K. Nakagawa, M. Ishiguro, K. Ueda, H. Ito [2004], “A
highly stable mm-wave synthesizer realized by mixing two lasers locked to an
optical frequency comb generator”, Opt. Commun. vol. 240, pp. 201-208.
Nakagiri
K, “Influence of Variable Capacitance Diode
Nakagiri,
K, and K Tanaka, “Phase Control of a Ramsey Resonance Cavity Using 2 Ring Type
Cavities of Cesium Beam Frequency Standard,” Proceedings
of ATF 2004, pp. 106-112.
Nakajima,
Y., K. Fujii, Y. Matsumoto, A. Sugiura, [2004], “A Calculable
Nakanishi, M., and J. Kinoshita [2003],
"Cryogenic current comparator bridge supplying current up to 1 A and
current dependence measurement of 1 W resistor,"Jpn. J. Appl. Phys.,
vol.42 no.10, pp 6641-6644.
Nakano,
H., T. Inoue and Y. Kato, [2002a], “Total Power Radiometer for Microwave Noise
Measurement”, AIST Bulletin of Metrology, vol.1, no.1, pp.29-35
Nakano,
H., H. Murakami, T. Inoue and Y. Kato [2002b], “An Experimental for
Verification of the Auxiliary Transmission-Line Method to Evaluate a Microwave
Thermal Noise Source”, CPEM 2002 Conference Digest, pp.72-73
Nakano,
H., H. Murakami, T. Inoue and Y. Kato [2003], “An Experimental for Verification
of the Auxiliary Transmission-Line Method to Evaluate a Microwave Thermal Noise
Source”, IEEE Trans. Instrum. Meas., vol.52, no.2, pp.306-310
Nishinaka H., Y. Sakamoto, Y. Murayama and A.
Iwasa [2002], "Effects of environmental conditions of some Zener voltage
references," CPEM '02 Conf. Dig. pp.166.
Ohtsuka,
T., N. Nishimiya, T. Fukuda and M. Suzuki [2005], "Doppler-Free Two-Photon
Spectroscopy of 6S1/2-6D3/2,5/2 Transition in Cesium", Jpn. J. Appl.
Phys., vol. 74, no. 9, to appear.
Otake,
M, K. Fukuda, M. Tachikawa, [2002], “High-resolution spectroscopy of
velocity-selected atoms in a thin cell,” Appl. Phys. B, vol.74, pp.503-508
Sakamoto, Y., and H. Fujiki [2002], "Dc voltage divider calibration
system at NMIJ", CPEM ‘02 Conference Digest, pp. 384-385.
Sakamoto, Y., and H. Fujiki [2003], "Dc voltage divider calibration
system at NMIJ", IEEE Trans. Instrum. Meas., vol. 52, no. 2, pp. 465-468.
Sakamoto, Y., [2004], "An alternative formulation for
uncertainty analysis with correlated estimates", CPEM ‘04 Conference
Digest, pp. 650-651.
Schibli,
T. R., K. Minoshima, F. -L. Hong, H. Inaba, A. Onae, H. Matsumoto, I. Hartl, M.
E. Fermann [2004], “Frequency metrology with a turnkey all-fiber system”, Opt.
Lett., vol. 29, no.21, pp. 2467-2469.
Shibuya,
Y., M. Imae [2002], “Compensation for ionospheric delay of common viewed GPS
time transfer in the Asia-Pacific region,” Proc. ATF2002, pp.138-145
Shibuya,
Y., Y. Fukuyama, M. Imae, M. Amemiya, T. Ikegami and S. Ohshima [2004],
“Development and Application of the Frequency Remote Calibration System in
Shimada,
Y [2003], “A survey on RF noise standard and its measurement system”, AIST
Bulletin of Metrology, vol.2, no.1, pp.147-158
Shimada,
Y [2004] “Recent Technology of Standard Measurement for Radio-Frequency Noise”,
MWE04 Microwave Workshop Digest, pp.445-450
Suzuki,
K., M. Koga, T. Morioka [2004], “MHz-accuracy, 25 GHz-spaced
frequency-stabilized optical comb over S-, C-, L-bands for precise optical
frequency measurements”, Electron. Lett., vol. 40, no. 17, pp. 1078-1079.
Takahashi, K., T. Takashima, and T. Yamada
[2004], “Bilateral Comparison of AC Current ratio Standards up to 700 Hz
between NMIJ and NRC”, CPEM Digest, pp.242-243, 2004.
Takahashi, K., T. Takashima [2004], “Ac Power
bridge at NMIJ”, CPEM Digest, pp.295-396, 2004.
Takahashi,
T., Y. Konishi, T. Noguchi, N. Futagawa, K. Kimura [2004], “Payload
configuration study for quasi zenith satellite system,” The 22th AIAA
International Communications Satellite Systems Conference & Exhibit 2004,
vol.AIAA2004-, no.3234
Takahashi,
Y., M. Imae, M. Aida, T. Gotoh, H. kiuchi, M. Hosokawa, H. Noda,
Takahashi,
Y., M. Imae, T. Gotoh, F. Nakagawa, H. kiuchi, M. Hosokawa, M. Aida, Y.
Takahashi, H. Noda, S. Hama [2004], “Time comparison equipment for ETS-VIII
satellite-part 1 development of flight model-,” Journal of the NICT, vol.50,
no.1/2, pp.135-143
Takahashi,
Y., M. Fujieda, L. Q. Tung, R. Tabuchi, F. Nakagawa, H. Maeno, M. Aida, T.
Suzuyama [2004], TWSTFT network status and pland in the Pacific-rim region,
ATF2004, pp.250-257
Takamoto,
M., F. -L. Hong, R. Higashi, H. Katori [2005], “An optical lattice clock”,
Nature, vol. 435, pp.321-324.Urano, C., A. Iwasa, Y. Murayama,
A. Shoji, H. Yamamori, and M. Ishizaki [2004], “ A Precise Measurement of a
NbN-based 1 V Programmable Josephson Voltage”, CPEM Digest, pp.340-341, 2004.
Wakai,
N., N. Kurihara, A. Otsuka [2004a], “Numerical methed for caluculating LF
sky-wave,graund-wave and their resultant wave field strengths,” IEE,vol.140,
no.5, pp.288-291
Watabe,
K.,
Watabe,
K., Y. Koga,
Watabe
K., J. G. Hartnett, G. Santarelli, S. Yanagimachi, T. Ikegami, S. Ohshima
[2004b], "Development of microwave local oscillator synthesized from a
cryogenic sapphire oscillator at NMIJ/AIST," Proc. Asia-Pacific Workshop
on Time and Frequency, pp.114-117.
Widarta,
A. and T. Kawakami [2002a], “Attenuation measurement system in the frequency
range of 10 to 100 MHz,” CPEM 2002 Conf. Digest，MoP38，pp.80-81.
Widarta,
A., and T. Kawakami [2002b], “Dual channel IF substitution measurement system
for microwave attenuation standard,” 2002 APMC Proceedings，THOF84，pp.1331-1333.
Widarta,
A. and T. Kawakami [2002c], “Optical fibre isolation in RF dual channel
measurement systems,” Electronics Letters,vol.38-17,pp.957-958.
Widarta,
A. and T. Kawakami [2003a], “Attenuation measurement system in the frequency
range of 10 to 100 MHz,” IEEE Trans.on IM，vol.52-2，pp.302-305.
Widarta,
A., T. Kawakami and K. Suzuki [2003b], “Dual channel IF substitution
measurement system for microwave attenuation standard,” IEICE Trans. on
Electron.，vol. E86-C-8，pp.1580-1583.
Widarta,
A., T. Kawakami and K. Komiyama [2003c], “Optical fiber link for perfect
isolation in microwave dual channel measurement system,” APMC'03 Proceedings，01-WEP-67，pp.584-586.
Widarta,
A., D. Sugawara, T. Kawakami and K. Komiyama [2004], “
Yanagimachi,
S., Y. Fukuyama, T. Ikegami, T. Kurosu [2004], "Numerical simulation of
distributed cavity phase shift in an atomic fountain frequency standard," 2004
Conference on Precision Electromagnetic Measurement Digest, pp.433-434.
Yonenaga, A., and Y. Nakamura [2004],
"Inductance calibration method using a commercial LCR meter," CPEM
‘04 Digest, pp. 597-598.