The Experts below are selected from a list of 8865 Experts worldwide ranked by ideXlab platform
Hidenori Muramatsu - One of the best experts on this subject based on the ideXlab platform.
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Comparison experiments on hybrid and biconical/LPD antennas in Radiated Emission measurement below 1 GHz
2015 Asia-Pacific Symposium on Electromagnetic Compatibility (APEMC), 2015Co-Authors: Ikuo Makino, Shinichi Okuyama, Hiroyuki Shimanoe, Hidenori MuramatsuAbstract:In Radiated Emission measurement below 1 GHz, it is a common practice to use broadband antennas such as biconical antennas and LPD antennas. Another practice is to use hybrid antennas because they do not require replacement of the antenna throughout the frequency range below 1 GHz. While the use of a hybrid antenna at a 10 m distance is viewed as a viable option, its use at a 3 m distance is sometimes questioned because of technical issues. Comparison experiments in this paper aim to validate these issues and study the viability of hybrid antennas in Radiated Emission measurement below 1 GHz at a 3 m distance.
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improvement of Radiated Emission measurement reproducibility with vhf lisn obtained from final results of international inter laboratory comparison on termination control of power line
Asia-Pacific Symposium on Electromagnetic Compatibility, 2015Co-Authors: Shinichi Okuyama, Nobuo Kuwabara, Kunihiro Osabe, Hidenori MuramatsuAbstract:At present, power supply impedance of Radiated Emission measurement site is not specified in any testing standards. In measurement of Radiated Emission from desktop equipment, noise emitted from power line of the EUT is a factor that worsens site correlations because the noise varies with the impedance between power line and the ground. Under such circumstances, VCCI developed VHF-LISN to stabilize power supply facilities for the purpose of improving the reproducibility of Radiated Emission measurement. To assess its effectiveness, an international inter-laboratory comparison program was carried out, provided with EUTs and termination control devices including the VHF-LISN to ensure identical setup across sites. Until February 2014, this international program was promoted at 16 sites in 9 countries. From the final results, we conclude that the VHF-LISN is the best device to improve the reproducibility of Radiated Emission measurement.
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Investigation on the effect of impedance changes in broadband antennas with varying antenna height on Radiated Emission measurement below 1 GHz
2015 IEEE International Symposium on Electromagnetic Compatibility (EMC), 2015Co-Authors: Shinichi Okuyama, Ikuo Makino, Hiroyuki Shimanoe, Hidenori MuramatsuAbstract:According to the standard method for calibration of receive antennas to be used in Radiated Emission measurement below 1 GHz, the sensitivity of receive antenna is defined as a free-space antenna factor obtained by applying a given correction factor to a near free-space factor that is determined by horizontally polarized antenna calibration at a 2 m antenna height. In actual Radiated Emission measurement performed while varying the receive antenna height, however, the sensitivity of receive antenna varies with antenna impedance changes at different antenna heights. In this situation, the authors measured how the antenna impedance changes with the antenna height and examined how such impedance changes affect Radiated Emission measurement results, using biconical, log-periodic dipole, and hybrid antennas under test that are typical below 1 GHz. The authors also studied on a method to estimate an antenna height free from antenna impedance changes and suitable for obtaining free-space factors.
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Improvement of Radiated Emission measurement reproducibility by VHF-LISN — Interim results of international inter-laboratory comparison
2014 International Symposium on Electromagnetic Compatibility Tokyo, 2014Co-Authors: Shinichi Okuyama, Katsuyuki Tanakajima, Kunihiro Osabe, Hidenori MuramatsuAbstract:At present, Radiated Emission measurement standards do not specify the common mode impedance for the outlet terminal of mains network to equipment under test (EUT) in the test site. Because of the difference in the terminating condition of EUT power cable which dominantly causes Radiated Emission in the frequency range between 30 MHz and 300 MHz, Radiated Emission measurements of a tabletop EUT are poor in reproducibility. In an effort to resolve this issue, we developed a device called very high frequency line impedance stabilization network (VHF-LISN) and investigated its effectiveness. After performing the domestic inter-laboratory comparison, we proposed an international inter-laboratory comparison program to CISPR Subcommittee I, and the proposal was accepted. For the comparison purpose, we have investigated the reproducibility also by using a common mode absorbing device (CMAD) and a versatile coupling/decoupling network of AC mains for Emission testing (CDNE-M). This investigation is just in progress as a future work of CISPR SC-I WG2 until February, 2014. As a glance from an interim result, we could find that all devices are effective to improve the reproducibility of Radiated Emission measurement in comparison with the case of no such device. But also we were able to presume that the effectiveness of devices to the measurement reproducibility differs with the type of EUT.
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improvement of Radiated Emission measurement reproducibility by vhf lisn interim results of international inter laboratory comparison
International Symposium on Electromagnetic Compatibility, 2014Co-Authors: Shinichi Okuyama, Katsuyuki Tanakajima, Kunihiro Osabe, Hidenori MuramatsuAbstract:At present, Radiated Emission measurement standards do not specify the common mode impedance for the outlet terminal of mains network to equipment under test (EUT) in the test site. Because of the difference in the terminating condition of EUT power cable which dominantly causes Radiated Emission in the frequency range between 30 MHz and 300 MHz, Radiated Emission measurements of a tabletop EUT are poor in reproducibility. In an effort to resolve this issue, we developed a device called very high frequency line impedance stabilization network (VHF-LISN) and investigated its effectiveness. After performing the domestic inter-laboratory comparison, we proposed an international inter-laboratory comparison program to CISPR Subcommittee I, and the proposal was accepted. For the comparison purpose, we have investigated the reproducibility also by using a common mode absorbing device (CMAD) and a versatile coupling/decoupling network of AC mains for Emission testing (CDNE-M). This investigation is just in progress as a future work of CISPR SC-I WG2 until February, 2014. As a glance from an interim result, we could find that all devices are effective to improve the reproducibility of Radiated Emission measurement in comparison with the case of no such device. But also we were able to presume that the effectiveness of devices to the measurement reproducibility differs with the type of EUT.
Inchae Song - One of the best experts on this subject based on the ideXlab platform.
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effect of split power ground planes using stitching capacitors on Radiated Emission
Electronics Packaging Technology Conference, 2009Co-Authors: Inchae SongAbstract:In this paper, the Radiated Emissions generated by various split power/ground plane structures are studied. The magnetic field and electric field over the designed test pattern are simulated. Each of the results has different field pattern by bandwidth of signal frequency, gap space or gap location of the split ground gap. To reduce the Radiated Emission, the method for determining the gap space and the gap location are studied based on the return current distributions. Also, the magnetic near-fields are measured by the near field EMI scan over the test board with the different value and location of the stitching capacitors. These results show that the Radiated Emission on split power/ground structure can be reduced by optimizing its structure. Moreover, the values and locations of the stitching capacitor should be determined to minimize the discontinuity of the return current paths.
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Effect of split power/ground planes using stitching capacitors on Radiated Emission
2009 11th Electronics Packaging Technology Conference, 2009Co-Authors: Inchae SongAbstract:In this paper, the Radiated Emissions generated by various split power/ground plane structures are studied. The magnetic field and electric field over the designed test pattern are simulated. Each of the results has different field pattern by bandwidth of signal frequency, gap space or gap location of the split ground gap. To reduce the Radiated Emission, the method for determining the gap space and the gap location are studied based on the return current distributions. Also, the magnetic near-fields are measured by the near field EMI scan over the test board with the different value and location of the stitching capacitors. These results show that the Radiated Emission on split power/ground structure can be reduced by optimizing its structure. Moreover, the values and locations of the stitching capacitor should be determined to minimize the discontinuity of the return current paths.
Katsuyuki Tanakajima - One of the best experts on this subject based on the ideXlab platform.
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Improvement of Radiated Emission measurement reproducibility by VHF-LISN — Interim results of international inter-laboratory comparison
2014 International Symposium on Electromagnetic Compatibility Tokyo, 2014Co-Authors: Shinichi Okuyama, Katsuyuki Tanakajima, Kunihiro Osabe, Hidenori MuramatsuAbstract:At present, Radiated Emission measurement standards do not specify the common mode impedance for the outlet terminal of mains network to equipment under test (EUT) in the test site. Because of the difference in the terminating condition of EUT power cable which dominantly causes Radiated Emission in the frequency range between 30 MHz and 300 MHz, Radiated Emission measurements of a tabletop EUT are poor in reproducibility. In an effort to resolve this issue, we developed a device called very high frequency line impedance stabilization network (VHF-LISN) and investigated its effectiveness. After performing the domestic inter-laboratory comparison, we proposed an international inter-laboratory comparison program to CISPR Subcommittee I, and the proposal was accepted. For the comparison purpose, we have investigated the reproducibility also by using a common mode absorbing device (CMAD) and a versatile coupling/decoupling network of AC mains for Emission testing (CDNE-M). This investigation is just in progress as a future work of CISPR SC-I WG2 until February, 2014. As a glance from an interim result, we could find that all devices are effective to improve the reproducibility of Radiated Emission measurement in comparison with the case of no such device. But also we were able to presume that the effectiveness of devices to the measurement reproducibility differs with the type of EUT.
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improvement of Radiated Emission measurement reproducibility by vhf lisn interim results of international inter laboratory comparison
International Symposium on Electromagnetic Compatibility, 2014Co-Authors: Shinichi Okuyama, Katsuyuki Tanakajima, Kunihiro Osabe, Hidenori MuramatsuAbstract:At present, Radiated Emission measurement standards do not specify the common mode impedance for the outlet terminal of mains network to equipment under test (EUT) in the test site. Because of the difference in the terminating condition of EUT power cable which dominantly causes Radiated Emission in the frequency range between 30 MHz and 300 MHz, Radiated Emission measurements of a tabletop EUT are poor in reproducibility. In an effort to resolve this issue, we developed a device called very high frequency line impedance stabilization network (VHF-LISN) and investigated its effectiveness. After performing the domestic inter-laboratory comparison, we proposed an international inter-laboratory comparison program to CISPR Subcommittee I, and the proposal was accepted. For the comparison purpose, we have investigated the reproducibility also by using a common mode absorbing device (CMAD) and a versatile coupling/decoupling network of AC mains for Emission testing (CDNE-M). This investigation is just in progress as a future work of CISPR SC-I WG2 until February, 2014. As a glance from an interim result, we could find that all devices are effective to improve the reproducibility of Radiated Emission measurement in comparison with the case of no such device. But also we were able to presume that the effectiveness of devices to the measurement reproducibility differs with the type of EUT.
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A method to evaluate Radiated Emission test sites above 1 GHz using propagation loss of different polarization
2013 Asia-Pacific Symposium on Electromagnetic Compatibility (APEMC), 2013Co-Authors: Atsuya Maeda, Katsuyuki Tanakajima, Shuichi Kobayashi, Takayoshi Suda, Hidenori MuramatsuAbstract:Site VSWR to evaluate Radiated Emission test sites above 1 GHz is defined by CISPR 16-1-4. However, the Site VSWR has been specified without theoretical basis and its limit was also changed several times without reasonable grounds. We confirmed that site attenuation is suitable for evaluation of Radiated Emission test sites above 1 GHz and we devised a method to evaluate Radiated Emission test sites above 1 GHz as free-space by means of wave propagation measurements using a conical dipole antenna that was developed the idea of site attenuation measurement. We confirmed the advantage and practical usefulness of the method using propagation loss of different polarization to use evaluation for Radiated Emission test sites above 1 GHz.
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A round-robin test on effectiveness of a VHF LISN for Radiated Emission measurements
2011 IEEE International Symposium on Electromagnetic Compatibility, 2011Co-Authors: Chiharu Miyazaki, Katsuyuki Tanakajima, Masanori Yamaguchi, Hidenori Muramatsu, Kiyoshi Endo, Jiro KawanoAbstract:VCCI Technical Sub-committee has investigated the dispersion of Radiated Emission measurement results. It was confirmed that one of the main cause of the dispersion of Radiated Emission measurement results was the difference of the power line-to-ground impedance of the power supply for the equipment under test (EUT). For the improvement of the dispersion, VCCI Council manufactured the experimental VHF LISN (Very High Frequency Line Impedance Stabilization Network). And we performed a round-robin test on the effectiveness of the VHF LISN.
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Improvement of dispersion of Radiated Emission measurement results by VHF-LISN
2008 IEEE International Symposium on Electromagnetic Compatibility, 2008Co-Authors: Chiharu Miyazaki, Katsuyuki Tanakajima, Masanori Yamaguchi, Shozo Satake, Jiro KawanoAbstract:VCCI* Technical Sub-committee has investigated the dispersion of Radiated Emission measurement results . It was confirmed that one of the main cause of the dispersion of Radiated Emission measurement results was the difference of the power line-to-ground impedance of the power supply for the equipment under test (EUT). For the improvement of the dispersion, VCCI manufactured the experimental VHF-LISN (very high frequency-line impedance stabilization network). And we confirmed the validity of this VHF-LISN.
Shinichi Okuyama - One of the best experts on this subject based on the ideXlab platform.
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Comparison experiments on hybrid and biconical/LPD antennas in Radiated Emission measurement below 1 GHz
2015 Asia-Pacific Symposium on Electromagnetic Compatibility (APEMC), 2015Co-Authors: Ikuo Makino, Shinichi Okuyama, Hiroyuki Shimanoe, Hidenori MuramatsuAbstract:In Radiated Emission measurement below 1 GHz, it is a common practice to use broadband antennas such as biconical antennas and LPD antennas. Another practice is to use hybrid antennas because they do not require replacement of the antenna throughout the frequency range below 1 GHz. While the use of a hybrid antenna at a 10 m distance is viewed as a viable option, its use at a 3 m distance is sometimes questioned because of technical issues. Comparison experiments in this paper aim to validate these issues and study the viability of hybrid antennas in Radiated Emission measurement below 1 GHz at a 3 m distance.
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improvement of Radiated Emission measurement reproducibility with vhf lisn obtained from final results of international inter laboratory comparison on termination control of power line
Asia-Pacific Symposium on Electromagnetic Compatibility, 2015Co-Authors: Shinichi Okuyama, Nobuo Kuwabara, Kunihiro Osabe, Hidenori MuramatsuAbstract:At present, power supply impedance of Radiated Emission measurement site is not specified in any testing standards. In measurement of Radiated Emission from desktop equipment, noise emitted from power line of the EUT is a factor that worsens site correlations because the noise varies with the impedance between power line and the ground. Under such circumstances, VCCI developed VHF-LISN to stabilize power supply facilities for the purpose of improving the reproducibility of Radiated Emission measurement. To assess its effectiveness, an international inter-laboratory comparison program was carried out, provided with EUTs and termination control devices including the VHF-LISN to ensure identical setup across sites. Until February 2014, this international program was promoted at 16 sites in 9 countries. From the final results, we conclude that the VHF-LISN is the best device to improve the reproducibility of Radiated Emission measurement.
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Investigation on the effect of impedance changes in broadband antennas with varying antenna height on Radiated Emission measurement below 1 GHz
2015 IEEE International Symposium on Electromagnetic Compatibility (EMC), 2015Co-Authors: Shinichi Okuyama, Ikuo Makino, Hiroyuki Shimanoe, Hidenori MuramatsuAbstract:According to the standard method for calibration of receive antennas to be used in Radiated Emission measurement below 1 GHz, the sensitivity of receive antenna is defined as a free-space antenna factor obtained by applying a given correction factor to a near free-space factor that is determined by horizontally polarized antenna calibration at a 2 m antenna height. In actual Radiated Emission measurement performed while varying the receive antenna height, however, the sensitivity of receive antenna varies with antenna impedance changes at different antenna heights. In this situation, the authors measured how the antenna impedance changes with the antenna height and examined how such impedance changes affect Radiated Emission measurement results, using biconical, log-periodic dipole, and hybrid antennas under test that are typical below 1 GHz. The authors also studied on a method to estimate an antenna height free from antenna impedance changes and suitable for obtaining free-space factors.
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Improvement of Radiated Emission measurement reproducibility by VHF-LISN — Interim results of international inter-laboratory comparison
2014 International Symposium on Electromagnetic Compatibility Tokyo, 2014Co-Authors: Shinichi Okuyama, Katsuyuki Tanakajima, Kunihiro Osabe, Hidenori MuramatsuAbstract:At present, Radiated Emission measurement standards do not specify the common mode impedance for the outlet terminal of mains network to equipment under test (EUT) in the test site. Because of the difference in the terminating condition of EUT power cable which dominantly causes Radiated Emission in the frequency range between 30 MHz and 300 MHz, Radiated Emission measurements of a tabletop EUT are poor in reproducibility. In an effort to resolve this issue, we developed a device called very high frequency line impedance stabilization network (VHF-LISN) and investigated its effectiveness. After performing the domestic inter-laboratory comparison, we proposed an international inter-laboratory comparison program to CISPR Subcommittee I, and the proposal was accepted. For the comparison purpose, we have investigated the reproducibility also by using a common mode absorbing device (CMAD) and a versatile coupling/decoupling network of AC mains for Emission testing (CDNE-M). This investigation is just in progress as a future work of CISPR SC-I WG2 until February, 2014. As a glance from an interim result, we could find that all devices are effective to improve the reproducibility of Radiated Emission measurement in comparison with the case of no such device. But also we were able to presume that the effectiveness of devices to the measurement reproducibility differs with the type of EUT.
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improvement of Radiated Emission measurement reproducibility by vhf lisn interim results of international inter laboratory comparison
International Symposium on Electromagnetic Compatibility, 2014Co-Authors: Shinichi Okuyama, Katsuyuki Tanakajima, Kunihiro Osabe, Hidenori MuramatsuAbstract:At present, Radiated Emission measurement standards do not specify the common mode impedance for the outlet terminal of mains network to equipment under test (EUT) in the test site. Because of the difference in the terminating condition of EUT power cable which dominantly causes Radiated Emission in the frequency range between 30 MHz and 300 MHz, Radiated Emission measurements of a tabletop EUT are poor in reproducibility. In an effort to resolve this issue, we developed a device called very high frequency line impedance stabilization network (VHF-LISN) and investigated its effectiveness. After performing the domestic inter-laboratory comparison, we proposed an international inter-laboratory comparison program to CISPR Subcommittee I, and the proposal was accepted. For the comparison purpose, we have investigated the reproducibility also by using a common mode absorbing device (CMAD) and a versatile coupling/decoupling network of AC mains for Emission testing (CDNE-M). This investigation is just in progress as a future work of CISPR SC-I WG2 until February, 2014. As a glance from an interim result, we could find that all devices are effective to improve the reproducibility of Radiated Emission measurement in comparison with the case of no such device. But also we were able to presume that the effectiveness of devices to the measurement reproducibility differs with the type of EUT.
Jiro Kawano - One of the best experts on this subject based on the ideXlab platform.
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A round-robin test on effectiveness of a VHF LISN for Radiated Emission measurements
2011 IEEE International Symposium on Electromagnetic Compatibility, 2011Co-Authors: Chiharu Miyazaki, Katsuyuki Tanakajima, Masanori Yamaguchi, Hidenori Muramatsu, Kiyoshi Endo, Jiro KawanoAbstract:VCCI Technical Sub-committee has investigated the dispersion of Radiated Emission measurement results. It was confirmed that one of the main cause of the dispersion of Radiated Emission measurement results was the difference of the power line-to-ground impedance of the power supply for the equipment under test (EUT). For the improvement of the dispersion, VCCI Council manufactured the experimental VHF LISN (Very High Frequency Line Impedance Stabilization Network). And we performed a round-robin test on the effectiveness of the VHF LISN.
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Improvement of dispersion of Radiated Emission measurement results by VHF-LISN
2008 IEEE International Symposium on Electromagnetic Compatibility, 2008Co-Authors: Chiharu Miyazaki, Katsuyuki Tanakajima, Masanori Yamaguchi, Shozo Satake, Jiro KawanoAbstract:VCCI* Technical Sub-committee has investigated the dispersion of Radiated Emission measurement results . It was confirmed that one of the main cause of the dispersion of Radiated Emission measurement results was the difference of the power line-to-ground impedance of the power supply for the equipment under test (EUT). For the improvement of the dispersion, VCCI manufactured the experimental VHF-LISN (very high frequency-line impedance stabilization network). And we confirmed the validity of this VHF-LISN.
