, 31, 3 (2007) 113 118

J. Inst. Electrostat. Jpn.

Ꮺ㔚ߒߚੱ૕߆ࠄߩ᡼㔚㔚ᵹᵄᒻߩᤨ㑆㧙๟ᵄᢙ⸃ᨆศ ↰ ቁ ඳ*,1㧘ਭ଻↰ ໪ ๋**㧘Ỉ ੗ ਂ ᓼ***㧘Ⴧ ੗ ౖ ᣿*
㧔2006 ᐕ 11 ᦬ 8 ᣣฃઃ㧧2007 ᐕ 3 ᦬ 13 ᣣฃℂ㧕Time-Frequency Analysis of Discharge Current
from Charged Human Body
Takahiro YOSHIDA*,1, Keigo KUBOTA*, Takenori SAWAI* and Noriaki MASUI*(Received November 8, 2006; Accepted March 13, 2007)

In this paper, we propose to adopt time-frequency analysis using the spectrogram to analyze electrostatic discharge
events. The time-frequency analysis enables to analyze the local frequency distribution of current waveform. As theapplication of this spectrogram, we analyze the waveforms of discharge currents from the charged human body.
Body potential is from ±2kV to ±10kV. The trends in the discharge from the charged human body are that most of thewaveforms have fast rise and large peak value at the wavefront, when the body potential is lower than +4kV. It isfound that the high frequency component is included in the wavefront of the discharge current by using thetime-frequency analysis. Especially, in the case of the waveforms for +4kV, most wavefront of the discharge current
contains the frequency component over 500MHz. When the body potential is higher than +6kV and negative,frequency component is even in the maximum around 200MHz. Frequency component from DC to 20MHz withlarger power is included behind the wavefront of the discharge current.
1.

ߪߓ߼ߦߪ㧘Ꮺ㔚૕ߩ⒳㘃㧘Ꮺ㔚㔚࿶߅ࠃ߮ᭂᕈߥߤߩ᡼㔚᧦ઙߩ㆑㔚ሶᯏེ߿ඨዉ૕࠺ࡃࠗࠬ߇ᓸ⚦ൻߔࠆߣߣ߽ߦ㧘㕒㔚᳇޿ߦࠃࠅ⃻ࠇࠆ⃻⽎ߩᄌൻࠍᝒ߃ࠆᔅⷐ߇޽ࠆ㧚ߘߩߚ߼᡼㔚(ESD : Electrostatic Discharge)ߦࠃࠆ⺋૞േ߿⎕უߥߤߩᚒ‫ߪޘ‬㧘ੱ૕߆ࠄߩ㕒㔚᳇᡼㔚ߦࠃࠆ᡼㔚㔚ᵹࠍ᷹ቯߒ㧘ߘ㕒㔚᳇㓚ኂ߇㗫⊒ߒߡ޿ࠆ㧚⃻࿷㧘㔚ሶᯏེߩ㕒㔚᳇⠴ᕈࠍߩ㔚ᵹᵄᒻߩᒻ⁁㧘߅ࠃ߮᡼㔚ࠡࡖ࠶ࡊ㐳㧘ᜰవ਄ߩ᡼㔚〝⹏ଔߔࠆᣇᴺߩ৻ߟߣߒߡ㧘ੱ૕Ꮺ㔚ࡕ࠺࡞(HBM㧦Humanߩࡄ࠲࡯ࡦࠍ᠟ᓇߒߚ౮⌀㧘᡼㔚㔚⩄㊂ߥߤߦࠃࠅᄙⷺ⊛ߦBody Model)߇޽ࠆ㧚HBM ߪ㧘Ꮺ㔚ߒߚੱ૕ࠍࠦࡦ࠺ࡦࠨߢᲧセ࡮ᬌ⸛ࠍⴕߞߡ߈ߚ 1,3,4,5)㧚

⟎߈឵߃㧘᡼㔚ᛶ᛫ࠍ੺ߒߡࠦࡦ࠺ࡦࠨߦల㔚ߒߚ㔚⩄ࠍ᡼ᓥ᧪ࠃࠅ㧘᡼㔚㔚ᵹ߿᡼኿㔚⏛ࡁࠗ࠭ߩಽᨆߢߪ㧘ᵄᒻో㔚ߐߖࠆߎߣߦࠃࠅ㧘ੱ૕߆ࠄߩ᡼㔚ࠍౣ⃻ߒߡ޿ࠆ㧚ߒ߆૕ߦኻߒߡ㜞ㅦࡈ࡯࡝ࠛᄌ឵㧔Fast Fourier Transform㧕ࠍ↪޿ߒ㧘ታ㓙ߩੱ૕ߣធ࿾㊄ዻ㑆ߩ᡼㔚㔚ᵹᵄᒻߪ㧘Ꮺ㔚ᭂᕈ߿ߡ᳞߼ࠄࠇࠆࠬࡍࠢ࠻࡞ߦࠃࠆ๟ᵄᢙ⸃ᨆ߇ᐢߊⴕࠊࠇߡ㧘޿ࠆ 6,7)㧚ߒ߆ߒ㧘ࠬࡍࠢ࠻࡞ߢߪ᡼㔚㔚ᵹ߿᡼኿㔚⏛ࡁࠗ࠭㕒㔚᳇㓚ኂߣ㕒㔚᳇᡼㔚⃻⽎ߣߩ㑐ㅪᕈࠍ⸃᣿ߔࠆߚ߼ߦߩᵄᒻߩฦᤨ㑆૏⟎ߦኻߔࠆዪᚲ⊛ߥ๟ᵄᢙ․ᕈ߹ߢߪᓧ

Ꮺ㔚㔚࿶㧘߹ߚⵍ㛎⠪ߦ߽ଐሽߔࠆߎߣ߇್᣿ߒߡ߅ࠅ1,2)

ࠠ࡯ࡢ࡯࠼㧦ESD㧘 HBM㧘᡼㔚㔚ᵹ㧘ࠬࡍࠢ࠻ࡠࠣ࡜ࡓ* ᧲੩ℂ⑼ᄢቇ Ꮏቇㇱ 㔚᳇Ꮏቇ⑼㧔102-0073 ᧲੩ㇺජઍ↰඙਻Ბർ 1-14-6㧕
Department of Electrical Engineering, Tokyo University ofScience, 1-14-6, Kudan-kita, Chiyoda-ku, Tokyo 102-0073,
Japan** ᩣᑼળ␠ኹጟ⵾૞ᚲ ⎇ⓥ㐿⊒ᧄㇱ ↢↥ᛛⴚ⎇ⓥㇱ
㧔140-8711 ᧲੩ㇺຠᎹ඙ᐢ↸ 1-4-22㧕
Technical Engineering Department, Teraoka Seisakusho
Co.,Ltd., 1-4-22, Hiromachi, Shinagawa-ku, Tokyo 140-8711,
Japan*** ࠮ࠗࠦ࡯ࠛࡊ࠰ࡦᩣᑼળ␠㧔392-8502 㐳㊁⋵⺪⸰Ꮢᄢ๺3-3-5㧕
SEIKO EPSON Corp., 3-3-5, Owa, Suwa city, Nagano392-8502, Japan1
yoshida@ee.kagu.tus.ac.jpࠄࠇߥ޿໧㗴߇޽ߞߚ㧚߹ߚ㧘ઁߩ๟ᵄᢙ⸃ᨆᴺߣߒߡߪ㧘㚍᧖߇ Wavelet ࠍ↪޿ߡᄙ㊀⸃௝ᐲ⸃ᨆࠍⴕ޿㧘㕒㔚᳇᡼㔚ߩ EMI ⹏ଔࠍⴕߞߚႎ๔ 8)߽޽ࠆ߇㧘᡼㔚㔚ᵹᵄᒻࠍฦ๟ᵄ
ᢙᏪၞᲤߦಽഀߒߡ๟ᵄᢙಽᨆࠍⴕߞߚ⚿ᨐߪ␜ߐࠇߡ޿ࠆ߽ߩߩ㧘ㅢᏱߩࠬࡍࠢ࠻࡞ห᭽㧘ฦᤨ㑆૏⟎ߦኻߔࠆ๟ᵄ
ᢙ․ᕈߪᓧࠄࠇߥ޿㧚᡼㔚㔚ᵹߩᵄᒻᒻ⁁ߪ㧘┙ߜ਄߇ࠅߩ㍈ߐ߿㧘1 ࿁ߩ᡼㔚ߦ߅޿ߡ಴⃻ߔࠆࡇ࡯ࠢ㔚ᵹߩᢙ߇⇣ߥࠆߥߤ㧘ⶄ㔀ߥ᭽⋧ࠍ␜ߔ㧚ߘߩߚ߼㧘ᵄᒻో૕ߦኻߒߡ๟ᵄᢙ⸃ᨆࠍⴕ߁ࠬࡍࠢ࠻࡞ߢߪ㧘ᵄᒻో૕ߩ᭽⋧ߒ߆ಽᨆߢ߈ߥ޿ὐ߇ᄢ߈ߥ໧㗴ߣߥࠆ㧚ߎࠇࠄ᡼㔚㔚ᵹ߿᡼኿㔚⏛ࡁࠗ࠭ߩߐࠄߥࠆᬌ⸛ࠍㅴ߼ࠆߚ߼ߦߪ㧘ᵄᒻߩߤߩㇱಽߦߤߩࠃ߁ߥ๟ᵄᢙᚑಽ߇฽߹ࠇߡ޿ࠆߩ߆㧘߹ߚ㧘ᤨ㑆ߣ౒ߦ114 (32)3132007๟ᵄᢙᚑಽ߇ߤߩࠃ߁ߦᄌൻߒߡࠁߊߩ߆ࠍ᷹ⷰߢ߈ࠆ๟㪞㪸㫇 㪣㪼㫅㪾㫋㪿 㪦㫊㪺㫀㫃㫃㫆㫊㪺㫆㫇㪼㪚㫌㫉㫉㪼㫅㫋 㪧㫉㫆㪹㪼ᵄᢙಽᨆᴺ߇ᔅⷐߢ޽ࠆ㧚ᧄ⎇ⓥߢߪ㧘⍴ᤨ㑆ߩಽᨆࡈ࡟࡯ࡓࠍᤨ㑆ᣇะߦࠪࡈ࠻ߒ㧘ߘࠇߙࠇߩಽᨆࡈ࡟࡯ࡓߦኻߒߡ FFT ࠍⴕ߁ߎߣߢࠬࡍࠢ㪌㪞㱅㪛㪚㪯㪄㪪㫋㪸㪾㪼㪂㩷㫆㫉 㪄㪤㫆㫋㫆㫉࠻࡞ߩᤨ㑆゠〔ࠍᓧࠆ⸃ᨆᴺߢ޽ࠆࠬࡍࠢ࠻ࡠࠣ࡜ࡓࠍ೑㪚㫃㫌㫋㪺㪿↪ߔࠆߎߣߢ㧘㕒㔚᳇᡼㔚⃻⽎ߩᤨ㑆㧙๟ᵄᢙ⸃ᨆࠍⴕ߁ߎ㪠㫅㫊㫌㫃㪸㫋㫆㫉㪤㪼㫋㪸㫃 㪧㫃㪸㫋㪼ߣࠍឭ᩺ߒ㧘ታ㓙ߦ㧘Ꮺ㔚㔚࿶r2kV㨪r10kV ߦᏪ㔚ߒߚੱ૕߆ࠄߩ㕒㔚᳇᡼㔚ߩ᡼㔚㔚ᵹᵄᒻߩ⸃ᨆࠍⴕߞߚ㧚⸃ᨆᣇᴺߩ⹦⚦ߪઃ㍳ߦ␜ߔ㧚
2.
2.1

㪞㪸㫇㩷㪚㫆㫌㫅㫋㪼㫉㩽 㪚㫆㫅㫋㫉㫆㫃㫃㪼㫉࿑ 1 ታ㛎ⵝ⟎ߩ᭴ᚑ
Fig.1 Schematic view of the apparatus for measuring discharge
current.

ⵝ⟎෸߮ታ㛎ᣇᴺi1

᡼㔚㔚ᵹᵄᒻߩ᷹ቯ

i2

࿑ 1 ߦታ㛎ⵝ⟎࿑ࠍ␜ߔ㧚ធ࿾㊄ዻ᧼਄ߦ㊀ߨߚ⛘✼᧼ߩ਄ߦ⵻⿷ߢ┙ߞߚⵍ㛎⠪ࠍ㧘5Gǡߩᛶ᛫ࠍ੺ߒߡr2kV㨪
r10kV ߦల㔚ߒߚᓟ㧘㔚Ḯࠍಾࠅ㔌ߒ㧘ធ࿾ዉ૕⃿(⋥ᓘ
16mm ߩ⌀㎕⃿)ࠍ 0.4mm/s ߩㅦߐߢᜰవߦㄭߠߌ᡼㔚ߐߖࠆ㧚0᡼㔚ߩ⊒↢ߣหᤨߦ᡼㔚㐿ᆎࠡࡖ࠶ࡊ㐳ࠍ⸘᷹ߔࠆࠞ࠙ࡦ࠲ߣᓸേบ߇ᱛ߹ࠆ㧚᡼㔚㔚ᵹᵄᒻߪ㧘㔚ᵹࡊࡠ࡯ࡉ(㩉㩐㨺㩍㩂㩎㩥㩐㩂㩇 CT-1㧘Ꮺၞ 1GHz)ࠍ↪޿ߡ㔚࿶ᵄᒻߦᄌ឵ߒ㧘࠺ࠫ࠲

t2t1TimeT2pߢ᷹ⷰߒߚ㧚ߎߩ᷹ቯⵝ⟎߅ࠃ᷹߮ቯᣇᴺߪㆊ෰ߩႎ๔ 3)ߣ

࿑ 2 ᡼㔚㔚ᵹᵄᒻߩቯ⟵Fig.2 Definition of parameters of the waveform of discharge
current.

ห᭽ߢ޽ࠆ㧚ߥ߅㧘᡼㔚㔚ᵹߩ᷹ቯߦ޽ߚࠅ㧘᷹ቯߦᓇ㗀ࠍ

2.2ਈ߃ࠆዉ૕⃿߆ࠄߩ㈩✢ߪ㧘᭴ㅧ਄น⢻ߥ㒢ࠅ⍴〒㔌ߢធ࿾᡼㔚㔚ᵹᵄᒻߩᒻ⁁ࠍቯ㊂⊛ߦᬌ⸛ߔࠆߚ߼㧘ᒻ⁁ߩ․ᓽ

ߐߖߚ㧚ߒ߆ߒ㧘ታ㛎ⵝ⟎ߦߪᶋㆆኈ㊂߿ࠗࡦ࠳ࠢ࠲ࡦࠬߩ

ࠍ␜ߔࡄ࡜ࡔ࡯࠲ߣߒߡ㧘ࡇ࡯ࠢ߇ 2 ߟሽ࿷ߔࠆ 2 ࡇ࡯ࠢᵄᓇ㗀߇࿁ㆱߢ߈ߥ޿ⷐ⚛ߣߒߡౝ࿷ߔࠆ߇㧘ߎࠇࠄߩᓇ㗀ࠍᒻߦኻߒߡߪ㧘╙ 1 ࡇ࡯ࠢ࡮╙ 2 ࡇ࡯ࠢߩ┙ߜ਄߇ࠅፋᐲࠍ

ㆊ෰ߦᒰታ㛎ⵝ⟎ߦߡᬌ⸽ߒߚߣߎࠈ㧘᷹ቯ⚿ᨐߦࠊߕ߆ߥ

ߘࠇߙࠇ D1(=i1/t1)㧘D2(=i2/t2)㧘╙ 2 ࡇ࡯ࠢߩ಴⃻ᤨ㑆ࠍ T2p

ᓇ㗀ߪ⷗ࠄࠇࠆ߇㧘ᧄ⾰⊛ߥᏅߢߪߥ޿ߎߣࠍ⏕⹺ߒߡ޽ࠆ㧚ߣߒߡ㧘࿑ 2 ߩࠃ߁ߦቯ⟵ߒ᷹ቯࠍⴕߞߚ㧚ߐࠄߦ 3 ࡇ࡯ࠢ੹࿁ߩታ㛎ߢߪ㧘⊹⤏ᛶ᛫߇ᐔဋ 15.9Mǡ(ᄌേ▸࿐ 12.3M

ᵄᒻߦ߅޿ߡߪ㧘╙ 2 ࡇ࡯ࠢߣห᭽ߦ㧘╙ 3 ࡇ࡯ࠢߩ┙ߜ਄ǡ㨪20.6Mǡ)㧘
㕒㔚ኈ㊂߇ᐔဋ 182pF ߢ޽ࠆⵍ㛎⠪ߦኻߒߡ㧘߇ࠅፋᐲࠍ D3(=i3/t3)㧘╙ 3 ࡇ࡯ࠢߩ಴⃻ᤨ㑆ࠍ T3p ߣߒߡ᷹ฦࡄ࡜ࡔ࡯࠲㧔Ꮺ㔚㔚࿶࡮ᭂᕈ㧕Ფߦ 10 ࿁᷹ቯߒ㧘⸘ 200ቯࠍⴕߞߚ㧚ߎߎߢ㧘t1 ߪ㔚ᵹ୯ 0 ߆ࠄ╙ 1 ࡇ࡯ࠢߩࡇ࡯ࠢ

࿁ಽߩ᡼㔚㔚ᵹᵄᒻࠍᓧߚ㧚ಽᨆߪ㧘ߎࠇࠄߩ᷹ቯ࠺࡯࠲ో

㔚ᵹ i1 ߦ⥋ࠆ߹ߢߦⷐߔࠆᤨ㑆㧘t2 ߪ╙ 1 ࡇ࡯ࠢߣ╙ 2 ࡇ࡯ߡࠍ↪޿ߡ᡼㔚㔚ᵹߩ┙ߜ਄߇ࠅፋᐲ߅ࠃ߮ࡇ࡯ࠢ㔚ᵹࠍࠢߩ㑆ߩᭂዊ୯߆ࠄ㧘╙ 2 ࡇ࡯ࠢߩࡇ࡯ࠢ㔚ᵹ i2 ߦ⥋ࠆ߹ߢ᷹ቯߒߚ㧚ߥ߅㧘ᧄᢥਛߢ␜ߔ᡼㔚㔚ᵹᵄᒻߩᵄᒻᒻ⁁߿ࠬߦⷐߔࠆᤨ㑆ߣߒߚ㧚࡞ࠝࠪࡠࠬࠦ࡯ࡊ (Tektronix TDS5052㧘Ꮺၞ 500MHz㧘5GS/s)᡼㔚㔚ᵹᵄᒻߩᒻ⁁᷹ቯࡍࠢ࠻ࡠࠣ࡜ࡓߩ࿑ߪ㧘Ꮺ㔚㔚࿶࡮Ꮺ㔚ᭂᕈᲤߦ㗫಴ߔࠆઍ⴫⊛ߥᵄᒻᒻ⁁ߩ࠺࡯࠲ 1 ߟࠍㆬ೎ߒߡ↪޿ߚ⚿ᨐߢ޽ࠆ㧚3.

৻ᣇ㧘Ꮺ㔚㔚࿶ߩ㆑޿ߦࠃࠆᲧセߢߪ㧘ో᷹ቯ࠺࡯࠲ࠍ᡼㔚

3.1

㔚ᵹᵄᒻߩࡇ࡯ࠢᢙᲤߦಽ㘃ߒ㧘ᐔဋ୯ߦࠃࠅᲧセߒߚ㧚ੱ࿑ 3 ߦ㧘Ꮺ㔚㔚࿶ࠍ+2kV㨪+10kV ߩ㑆ߢ 2kV ೞߺߢᄌൻ

૕ߩ㕒㔚ኈ㊂෸߮⊹⤏ᛶ᛫ߪ㧘ㆊ෰ߦႎ๔ߒߚᣇᴺࠍ↪޿ߡߐߖߚߣ߈ߩᱜ᡼㔚ᤨߩ᡼㔚㔚ᵹᵄᒻࠍ␜ߔ㧚ߥ߅㧘ߎߩ᡼3)⚿ᨐ෸߮⠨ኤ
᡼㔚㔚ᵹᵄᒻߣࠬࡍࠢ࠻ࡠࠣ࡜ࡓߣߩ㑐ଥ᷹ቯߒߚ 㧚ߥ߅㧘੹࿁ߩ᷹ቯߢߪ㧘⊹⤏ᛶ᛫ߪฦ᷹ቯᣣᲤ㔚㔚ᵹᵄᒻߩᤨ㑆ゲߪ㧘᡼㔚㐿ᆎࠍᤨ㑆૏⟎ 0ns ߦឥ߃㧘ߩ᡼㔚ታ㛎೨࡮ታ㛎ਛ࡮ታ㛎ᓟߦ᷹ቯࠍⴕ޿㧘ᐔဋ୯ߣ㧘ᄌ-100ns㨪1000ns ߩ▸࿐ࠍ⴫␜ߒߚ㧚࿑ਛߩ⍫ශߪ㧘ฦ᡼㔚㔚േ▸࿐ࠍ᳞߼ߚ㧚ታ㛎ߪᐔဋ⋧ኻḨᐲ 40.9%㧔ᄌേ▸࿐ 35.0%ᵹᵄᒻߩ╙ 1 ࡇ࡯ࠢߩ᡼㔚㔚ᵹ୯ࠍ␜ߒߡ޿ࠆ㧚࿑ 4 ߦ㧘ฦ㨪47.7%㧕㧘ᐔဋ᷷ᐲ 23.1͠㧔ᄌേ▸࿐ 20.0͠㨪25.0͠㧕ߩᥧᏪ㔚㔚࿶ߦ߅ߌࠆ᡼㔚㔚ᵹᵄᒻࠃࠅ᳞߼ߚࠬࡍࠢ࠻ࡠࠣ࡜

ቶߢⴕߞߚ㧚

ࡓࠍ␜ߔ㧚115 (33)

dc1.5 ed0-100

400
300
200
100
0-50 0

0.5 a

[dB]

200

300

60
40
20
10200

300

400

-50

0

Time [ns]50

100

150 200

Time [ns](a) +2kV
a

100

[dB]

80

0100

b0100

400

500

Time [ns]

600

700

800

900

࿑ 3 ᡼㔚㔚ᵹᵄᒻ㧔ᱜ᡼㔚ᤨ㧕
Fig.3 Waveforms of typical positive discharge currents.

ߎߩࠬࡍࠢ࠻ࡠࠣ࡜ࡓߩᤨ㑆ゲߣ᡼㔚㔚ᵹᵄᒻߩᤨ㑆ゲࠍ⛔৻ߒ㧘᡼㔚㐿ᆎࠍᤨ㑆૏⟎ 0ns ߣߒߡឥ߃ߡ⴫␜ߒߚ㧚

1005001000

400Frequency [MHz]1.0cFrequency [MHz]Discharge current [A]

2.5 b
2.0500a: +2kVb: +4kV
c: +6kV
d: +8kV
e: +10kV

Frequency [MHz]eFrequency [MHz]

3.0

300
200
100
0-50 0ߥ߅㧘⷗߿ߔߐࠍ⠨ᘦߒߡ㧘࿑ 4 ਛߩᏀ஥ߩ࿑ߪ㧘ᐢ▸࿐ߩ

200

300

Frequency [MHz]

300
200
100

200

300

1000-50 0߅ࠃ߮⽶᡼㔚ߦ߅޿ߡ㧘Ꮺ㔚㔚࿶ߩ਄᣹ߣߣ߽ߦ㧘DC㨪
20MHz ⒟ᐲߩૐ޿๟ᵄᢙߦ㓸ਛߔࠆࠃ߁ߦߥࠆ㧚ߎߩૐ޿๟
ᵄᢙߦ߅ߌࠆᄢ߈ߥᝄ᏷ᚑಽ㧘ߟ߹ࠅᄢ߈ߥ᡼㔚㔚⩄㊂߇㧘

-50050100

150 200

8060
40
20
10200

300

400

-500Time [ns]

50

100

150 200

Time [ns](d) +8kV
100

500
400

Frequency [MHz]Frequency [MHz]ಽ߹ߢ฽߻௑ะ߇⷗ࠄࠇߚ㧚߽㧘ࠃࠅ㜞޿๟ᵄᢙᚑಽ߹ߢ฽߻௑ะ߇⃻ࠇߡ޿ࠆ㧚ᱜ᡼㔚

100100ߦ┙ߜ਄߇ࠅߩ㍈޿ᵄᒻ߇⷗ࠄࠇ㧘ߘߩㇱಽߢ㜞޿๟ᵄᢙᚑ

DC㨪100MHz ೨ᓟߦಽᏓߒߡ߅ࠅ㧘ᱜ᡼㔚ߩᣇ߇⽶᡼㔚ࠃࠅ

20100200ᨐࠃࠅ㧘ੱ૕߆ࠄߩ᡼㔚ߦ߅޿ߡߪ㧘ਥߦ㧘╙ 1 ࡇ࡯ࠢㇱಽߩ႐วߪ㧘DC㨪200MHz ೨ᓟߦಽᏓߒ㧘⽶᡼㔚ߩ႐วߦߪ㧘

40Time [ns]300ᢙᚑಽ߹ߢ৻᭽ߦ฽߻ᐢᏪၞାภߣߥࠆ߇㧘࿑ 3㨪࿑ 6 ߩ⚿␜ߔ㧚ኻᢙᝄ᏷୯߇ 15dB એ਄ߣߥࠆ๟ᵄᢙᏪၞߪ㧘ᱜ᡼㔚

60

400

Frequency [MHz]400

Frequency [MHz]3 ߅ࠃ߮࿑ 5 ߦ␜ߐࠇߚ᡼㔚㔚ᵹᵄᒻߪ㧘ฦᏪ㔚㔚࿶ߦ߅޿╙ 1 ࡇ࡯ࠢ߇ਥߦ┙ߜ਄߇ࠅፋᐲ߇ᄢ߈޿ࠗࡦࡄ࡞ࠬᒻ⁁ࠍ

150 200(c) +6kV500

㔚㔚࿶ో૕ߩ௑ะߣߒߡ㧘ᤨ㑆 1ns㨪20ns ߩ૏⟎ߦሽ࿷ߔࠆ

100

80

Time [ns]ߩ᡼㔚㔚ᵹᵄᒻࠍ㧘࿑ 6 ߦߘߩࠬࡍࠢ࠻ࡠࠣ࡜ࡓࠍ␜ߔ㧚࿑ߎࠇࠄߩࠬࡍࠢ࠻ࡠࠣ࡜ࡓߦ߅޿ߡ㧘r2kV㨪r10kV ߩᏪ

50

010055dB ߣߒߚ㧚ห᭽ߦ㧘
࿑ 5 ߦ⽶᡼㔚ᤨߩᏪ㔚㔚࿶-2kV㨪-10kVࠬᒻ⁁ߩᵄᒻߩ๟ᵄᢙ․ᕈߪ㧘ૐ޿๟ᵄᢙᚑಽ߆ࠄ㜞޿๟ᵄ

0100

ࠬࠤ࡯࡞ߩ▸࿐ߪᏀ஥ߩ࿑ߢߪ 0㨪45dB㧘ฝ஥ߩ࿑ߢߪ 0㨪৻⥸⊛ߦ㧘┙ߜ਄߇ࠅ࡮┙ߜਅ߇ࠅ߇ᭂ߼ߡ㍈޿ࠗࡦࡄ࡞

-50

Time [ns]4000-50 0࡞ߩኻᢙᝄ᏷୯ߪ⋧ኻ⊛ߥ୯ߢ޽ࠆߚ߼㧘න૏ dB ߢ޽ࠆ㧚ߡ㗫಴ߒߚઍ⴫⊛ߥᒻ⁁ߩᵄᒻߢ޽ࠆ㧚

10400500

Frequency [MHz]ࠢ࠻ࡠࠣ࡜ࡓฝ⢋ߦኻᢙᝄ᏷ߩࠬࠤ࡯࡞ࠍ␜ߔ߇㧘ࠬࡍࠢ࠻20(b) +4kV

ߪ㧘╙ 1 ࡇ࡯ࠢㄭறߩ᜛ᄢ࿑ߣߒߡ㧘ᤨ㑆૏⟎-50ns㨪200ns㧘ߡ߅ࠅ㧘⊕⦡ߦㄭ޿߶ߤᄢ߈ߊߥߞߡ޿ࠆ㧚࿑ 4(a)ߩฦࠬࡍ

40

Time [ns]㨪500MHz ߩ▸࿐ࠍ᛽಴ߒߡ⴫␜ߒߚ߽ߩߢ޽ࠅ㧘ฝ஥ߩ࿑ฦᤨ㑆㧘ฦ๟ᵄᢙߦ߅ߌࠆኻᢙᝄ᏷୯ߪ⦡ߩỚ᷆ߢ⴫⃻ߐࠇ

600100࿑ߣߒߡ㧘᡼㔚㔚ᵹᵄᒻߩᤨ㑆૏⟎-50ns㨪400ns㧘๟ᵄᢙ DC๟ᵄᢙ DC㨪100MHz ߩ▸࿐ࠍ᛽಴ߒߡ⴫␜ߒߚ߽ߩߢ޽ࠆ㧚

80

300
200
100
0-50 080
60
40
20
100100200300

400-50Time [ns]050100150 200

Time [ns](e) +10kV࿑ 4 ࠬࡍࠢ࠻ࡠࠣ࡜ࡓ(ᱜ᡼㔚)Fig.4 Spectrograms of typical positive discharge currents.

116 (34)ace-1.5-2.0

da: -2kV-2.5

b: -4kV
c: -6kV-3.0d: -8kV
e: -10ke-3.5-1000100200300

400500

600

700

800

900

400300200
1000-50 0100

[dB]

80604020100100200300

400-500

Time [ns]50100150 200

Time [ns](a) -2kV1000

᡼㔚㔚ᵹᵄᒻߩ╙ 1 ࡇ࡯ࠢએ㒠ߩ㔚ᵹ୯߇ᄢ߈޿൮⛊ㇱಽߦሽ࿷ߒߡ޿ࠆߎߣ߇ಽ߆ࠆ㧚

Frequency [MHz]࿑ 5 ᡼㔚㔚ᵹᵄᒻ㧔⽶᡼㔚ᤨ㧕
Fig.5 Waveforms of typical negative discharge currents.

100

500

Time [ns]3.2[dB]

Frequency [MHz]Discharge current [A]-1.0

2007

500bbd3400
300
200
1000-50 0᡼㔚㔚ᵹߩ┙ߜ਄߇ࠅፋᐲߣࠬࡍࠢ࠻ࡠࠣ࡜ࡓ

Frequency [MHz]a-0.5 cFrequency [MHz]031200300400࡯ࡊߩᏪၞ߇ 500MHz ߢ޽ࠆߚ߼㧘੹ᓟߪߐࠄߦᐢᏪၞߥࠝ

200
100

200300ਅߩૐ㔚࿶ߩᣇߩ EMI ૞↪߇ᒝ޿႐ว߇޽ࠆߣႎ๔ߒߡ޿
ࠆ㧚ᧄ⎇ⓥߢᓧࠄࠇߚ⚿ᨐߪ㧘ੱ૕߆ࠄߩ᡼㔚ߢ߽㧘ห᭽ߩߎߣ߇⿠ߎࠆߎߣࠍቯ㊂⊛ߦ⺑᣿ߒߡ޿ࠆ㧚⽶᡼㔚ߢߪ㧘
D1 ߪᐔဋ 0.071 A/ns㧘D2 ߪᐔဋ 0.014 A/ns ߣߥࠅ㧘╙ 1 ࡇ࡯ࠢߩ┙ߜ਄߇ࠅፋᐲ D1 ߪ㧘⽶᡼㔚ᤨࠃࠅ߽ᱜ᡼㔚ᤨߩᣇ߇

2010-50050

100

150 200

Time [ns]

200
100

80
60
40
20
100

100

200

300

400-500Time [ns]

50

100

150 200

Time [ns](d) -8kVߎߎߢߪขࠅ਄ߍߥ߆ߞߚઁߩⵍ㛎⠪ߢ߽㧘+4kV એਅߢ D1

100

500
400

Frequency [MHz]Frequency [MHz]߃ࠆ㧚ᧄ↰ 9)ߪ㧘㑆ធ ESD ߦ߅޿ߡߪ㜞㔚࿶ࠃࠅ߽ 3kV એ

40100㔚࿶ߢ߽㜞޿๟ᵄᢙᚑಽࠍ฽߻᡼㔚߇⃻ࠇࠆߎߣ߇ಽ߆ࠆ㧚ߢ޽ࠅ㧘╙ 1 ࡇ࡯ࠢߦ߅ߌࠆ๟ᵄᢙ․ᕈ߇ᷓߊ㑐ଥߔࠆߣ੔

60

400

300

0-50 0㛎⠪ߩ႐ว㧘Ꮺ㔚㔚࿶+4kV ߦ߅޿ߡᦨᄢߣߥࠅ㧘ૐ޿Ꮺ㔚৻᭎ߦᏪ㔚㔚࿶ߩᄢዊߢ㓚ኂߩᄢዊࠍ⹏ଔߔࠆߎߣߪ࿎㔍150 2000100

Frequency [MHz]400

Frequency [MHz]⇣ߥߞߡ޿ࠆ㧚࿑ 7 ߦ᡼㔚㔚ᵹߩ┙ߜ਄߇ࠅፋᐲߩᐔဋ୯ߣ

ࡁࠗ࠭ߦࠃࠅ↢ߕࠆ㔚ሶᯏེߩ⺋૞േ╬ߩ EMI ߦኻߒߡߪ㧘100(c) -6kV500

߇ᦨᄢߣߥࠆ⚿ᨐ߇ᓧࠄࠇߡ޿ࠆ㧚ߎࠇࠄߩ⚿ᨐ߆ࠄ㧘᡼኿

5080

Time [ns]ߩ┙ߜ਄߇ࠅፋᐲߣࡇ࡯ࠢ㔚ᵹ୯ߪ㧘Ꮺ㔚㔚࿶ߩ㆑޿ߦࠃࠅ

D1 ߪᏪ㔚㔚࿶ߦᲧ଀ߒߡᄢ߈ߊߥࠆࠊߌߢߪߥߊ㧘ߎߩⵍ

0100᡼㔚㔚ᵹߦ฽߹ࠇࠆ๟ᵄᢙᚑಽߦᓇ㗀ࠍਈ߃ࠆ᡼㔚㔚ᵹߚ߽ߩߢ޽ࠆ㧚ߎߩ࿑ࠃࠅ㧘╙ 1 ࡇ࡯ࠢߩ┙ߜ਄߇ࠅፋᐲ

-50

Time [ns]3000-50 0ࠪࡠࠬࠦ࡯ࡊߦࠃࠅታ㛎ࠍⴕ޿ᬌ⸛ߔࠆᔅⷐ߇޽ࠆ㧚ቯ࠺࡯࠲ࠍᏪ㔚㔚࿶ߣࡇ࡯ࠢᢙߢಽ㘃ߒߚ਄ߢᐔဋࠍ᳞߼

10400

Frequency [MHz]ߎߩࠃ߁ߥ㜞޿๟ᵄᢙᚑಽߪઁߩ᡼㔚ߢߪ⷗ࠄࠇߥ߆ߞߚ㧚

Frequency [MHz]500Ꮺ㔚㔚࿶ߩ㑐ଥࠍ␜ߔ㧚࿑ 7 ߩᐔဋ┙ߜ਄߇ࠅፋᐲߪ㧘ో᷹

20(b) -4kV

Ꮺၞ߇ DC㨪500MHz ߦಽᏓߔࠆ᡼㔚㔚ᵹᵄᒻ߇ᓧࠄࠇߚ㧚߇฽߹ࠇࠆน⢻ᕈ߇޽ࠆ߇㧘੹࿁ߩ᷹ቯߦ↪޿ߚࠝࠪࡠࠬࠦ

40Time [ns]Ꮺ㔚㔚࿶+4kV ᤨߦ㧘ኻᢙᝄ᏷୯ 15dB એ਄ߣߥࠆ๟ᵄᢙߥ߅㧘ߎࠇࠄߩᵄᒻߦ 500MHz એ਄ߩߐࠄߦ㜞޿๟ᵄᢙᚑಽ

600100ߣߩ㑐ଥ੹࿁ߩᏪ㔚㔚࿶+4kV ߩ᷹ቯߢߪ㧘50%ߩ㗫ᐲߢ಴⃻ߒߚ㧚

80

300
200
100
0-50 080604020100100

200300400-50Time [ns]

050

100

150 200

Time [ns](e) -10kV࿑ 6 ࠬࡍࠢ࠻ࡠࠣ࡜ࡓ(⽶᡼㔚)
Fig.6 Spectrograms of typical negative discharge currents.

117 (35)0.5ᭂᕈߦ㑐ࠊࠄߕㄭ޿୯ߣߥߞߡ޿ࠆ߇㧘Ꮺ㔚㔚࿶߇㜞޿߶ߤ㧘╙ 2 ࡇ࡯ࠢߩ┙ߜ਄߇ࠅፋᐲ D2 ߇ᄢ߈ߊߥߞߚ㧚
3.3

ࡇ࡯ࠢ㔚ᵹߣࠬࡍࠢ࠻ࡠࠣ࡜ࡓߣߩ㑐ଥ

Rise speed [A/ns]

ᐔဋ 3.3 ୚߶ߤᄢ߈޿㧚╙ 2 ࡇ࡯ࠢߩ┙ߜ਄߇ࠅፋᐲ D2 ߪ㧘

࿑ 8 ߦฦࡇ࡯ࠢ㔚ᵹߩᐔဋ୯ߣᏪ㔚㔚࿶ߩ㑐ଥࠍ␜ߔ㧚ߎ

0.2
0.1-6kV-4kV-2kV+2kV+4kV+6kV+8kV +10kV

Charged voltage࿑ 7 ᡼㔚㔚ᵹߩ┙ߜ਄߇ࠅፋᐲߩᐔဋ୯ߣᏪ㔚㔚࿶ߩ㑐ଥ
Fig.7 Relationship between average rising speed ofdischarge currents and charged voltage.

ಽ߆ࠆ㧚࿑ 4 ߅ࠃ߮࿑ 5 ߆ࠄࠊ߆ࠆࠃ߁ߦ㧘╙ 1 ࡇ࡯ࠢ㔚ᵹi1 ߪᵄᒻᒻ⁁ߦଐሽߔࠆߚ߼㧘Ꮺ㔚㔚࿶ߣߩ⋧㑐ᕈߪૐ޿㧚߹ߚ㧘ᱜ᡼㔚ᤨߦߪ㧘Ꮺ㔚㔚࿶߇+6kV ࠍ⿥߃ࠆߣ╙ 1 ࡇ࡯ࠢ㔚ᵹ i1 ࠃࠅ߽╙ 2 ࡇ࡯ࠢ㔚ᵹ i2 ߇ᄢ߈ߊߥࠆ㧚⽶᡼㔚ᤨߦ

3.5ߪ㧘Ꮺ㔚㔚࿶߇-4kV ࠍ⿥߃ࠆߣ㧘i1 ࠃࠅ߽ i2 ߇ᄢ߈ߊߥࠆ㧚

1st peak current, i1
2nd peak current, i2
3rd peak current, i3

3.0

Peak current [A]⒟ᐲߩૐ޿๟ᵄᢙᚑಽ߇Ⴧടߔࠆߎߣ߇ಽ߆ࠆ㧚

0.3-10kV -8kV2 ࡇ࡯ࠢ㔚ᵹ i2࡮╙ 3 ࡇ࡯ࠢ㔚ᵹ i3 ౒ߦ਄᣹ߒߡ޿ࠆߎߣ߇

ߒߡ╙ 2࡮╙ 3 ࡇ࡯ࠢ㔚ᵹ߇ᄢ߈ߊߥࠆߣ㧘ਥߦ DC㨪20MHz

Rise speed of 1st peak, D1
Rise speed of 2nd peak, D2
Rise speed of 3rd peak, D30.0ߩ࿑ࠃࠅ㧘Ꮺ㔚ᭂᕈߦ㑐ࠊࠄߕ㧘Ꮺ㔚㔚࿶ߩ਄᣹ߣ౒ߦ㧘╙ߎߩ⚿ᨐߣࠬࡍࠢ࠻ࡠࠣ࡜ࡓߣߩኻᔕ߆ࠄ㧘Ꮺ㔚㔚࿶ߦᲧ଀

0.4

2.5
2.0
1.5
1.0
0.5
0.0

4.

߹ߣ߼

ࠬࡍࠢ࠻ࡠࠣ࡜ࡓߦࠃࠆᤨ㑆㧙๟ᵄᢙ⸃ᨆࠍ↪޿ࠆߎߣߦࠃࠅ㧘એਅߦ␜ߐࠇࠆ᡼㔚㔚ᵹᵄᒻߩዪᚲ⊛ߢ․ᓽ⊛ߥᵄᒻᒻ⁁ߣߘߩㇱಽߦ฽߹ࠇࠆ๟ᵄᢙᚑಽߣߩ㑐ଥ߇⸃ᨆߢ߈㧘ᤨ㑆㧙๟ᵄᢙ⸃ᨆߪ㕒㔚᳇᡼㔚⃻⽎ߩಽᨆߦ߅޿ߡ᦭ല
ߢ޽ࠆߣ޿߃ࠆ㧚(1)ਥߦᱜ᡼㔚ᤨߩ╙ 1 ࡇ࡯ࠢߦ߅޿ߡ㧘┙ߜ਄߇ࠅ߇㍈޿ࡇ࡯ࠢࠍ߽ߟ᡼㔚㔚ᵹᵄᒻ߇಴⃻ߒ㧘ߎߩ╙ 1 ࡇ࡯ࠢߢߪ
500MHz ⒟ᐲ߹ߢߩ㜞޿๟ᵄᢙᚑಽࠍ฽߻․ᓽ߇޽ࠆ㧚-10kV-8kV-6kV-4kV-2kV+2kV

Charged voltage+4kV+6kV+8kV +10kV࿑ 8 ฦࡇ࡯ࠢ㔚ᵹߩᐔဋ୯ߣᏪ㔚㔚࿶ߩ㑐ଥ
Fig.8 Relationship between average peak currents andcharged voltage.
pp.849-850(1995)
10) ਃᶆ⒳ᢅ: ᣂ⡬ⷡߣ㖸ჿ, 㔚ሶᖱႎㅢାቇળ,pp.311-312(1980)11) ዊᨋ৻ⴕ: MATLAB ࡂࡦ࠼ࡉ࠶ࠢ, ⑲๺ࠪࠬ࠹ࡓ,pp.188(2004)
ઃ㍳ ࠬࡍࠢ࠻ࡠࠣ࡜ࡓߦࠃࠆᤨ㑆㧙๟ᵄᢙ⸃ᨆ

(2)Ꮺ㔚㔚࿶ߦᲧ଀ߒߡ╙ 2㧘╙ 3 ࡇ࡯ࠢ㔚ᵹ߇ᄢ߈ߊߥࠅ㧘᡼㔚㔚ᵹᵄᒻߩߤߩㇱಽߦߤߩࠃ߁ߥ๟ᵄᢙᚑಽ߇฽߹╙ 1 ࡇ࡯ࠢએ㒠ߩ㔚ᵹ୯߇ᄢ߈޿൮⛊ㇱಽߢߪ㧘
DC㨪20MHzࠇߡ޿ࠆߩ߆㧘߹ߚ㧘ᤨ㑆ߣ౒ߦ๟ᵄᢙᚑಽ߇ߤߩࠃ߁ߦᄌ⒟ᐲߩૐ޿๟ᵄᢙߦᚑಽ߇㓸ਛߒߡ޿ࠆ㧚ൻߒߡࠁߊߩ߆ࠍ᷹ⷰߔࠆߚ߼ߦ㧘ᧄ⎇ⓥߢߪࠬࡍࠢ࠻ࡠࠣ

(3)ᱜ᡼㔚ߩᣇ߇┙ߜ਄߇ࠅፋᐲ߇ᄢ߈ߊ㧘㜞๟ᵄᚑಽࠍ฽߻࡜ࡓࠍ↪޿ߡᤨ㑆㧙๟ᵄᢙ⸃ᨆࠍⴕߞߚ㧚଀ߣߒߡ㧘࿑ 9(a)᡼㔚㔚ᵹ߇⊒↢ߔࠆ㧚ߦ␜ߔ᡼㔚㔚ᵹߩᤨ㑆ᵄᒻߦኻߔࠆ㧘ࠬࡍࠢ࠻࡞ࠍ࿑ 9(b)ߦ㧘ࠬࡍࠢ࠻ࡠࠣ࡜ࡓࠍ࿑ 9(c)ߦ␜ߔ㧚ෳ⠨ᢥ₂1)ጟᔘผ㧘Ⴧ੗ౖ᣿㧦㕒㔚᳇ቇળ⹹㧘28㧘6㧘pp. 310-315(2004)
2) A.G. Bailey, J.M. Smallwood and H. Tomita: Inst. Phys. Conf.
Ser., No.118, Section 2, pp.101(1991)
ጟᔘผ㧘 Ⴧ੗ౖ᣿: 㕒㔚᳇ቇળᤐᦼ⻠Ṷળ⺰㧘
3)pp.29-30(2002)4) Ỉ੗ਂᓼ, ศ↰ቁඳ, Ⴧ੗ౖ᣿: 㕒㔚᳇㓚ኂ㒐ᱛᛛⴚࠪࡦࡐࠫ࠙ࡓ, pp.79-84(2004)5) Ỉ੗ਂᓼ, ศ↰ቁඳ, Ⴧ੗ౖ᣿: 㕒㔚᳇ቇળᤐᦼ⻠Ṷળ⺰, pp.5-8(2005)6) ᧄ↰᣽ ኪ: ╙ 15 ࿁ EOS/ESD/EMC ࠪࡦࡐ ࠫ ࠙ ࡓ,pp.83-90(2005)7) ฬข┨ੑ㧘๺↰ㄖᒾ㧘દ⮮⵨⬿㧘ဈ↰ඳ᡽㧘 ጟብᴦ㧘ᄢᵤቁ૫㧘↰ㄝ⧷↵: ╙ 15 ࿁ EOS/ESD/EMC ࠪࡦࡐࠫ࠙ࡓ,pp.91-95(2005)8) 㚍᧖ᱜ↵: 㔚ሶᖱႎㅢାቇળ⺰ᢥ⹹ B, Vol.J84-B, No.11㧘
pp2048-2058 (2001)9) ᧄ ↰ ᣽ ኪ : 㔚 ሶ ᖱ ႎ ㅢ ା ቇ ળ ⹹ 㧘 Vol.78 㧘 No.9 㧘ࠬࡍࠢ࠻ࡠࠣ࡜ࡓߪ㧘࿑ 10 ߦ␜ߔࠃ߁ߦಽᨆࡈ࡟࡯ࡓࠍᤨ㑆ᣇะߦࠪࡈ࠻ߒ㧘ߘࠇߙࠇߩಽᨆࡈ࡟࡯ࡓߦኻߒߡ㜞ㅦࡈ࡯࡝ࠛᄌ឵㧔FFT㧕ࠍⴕ߁ߎߣߢࠬࡍࠢ࠻࡞ߩᤨ㑆゠〔ࠍᓧࠆ⸃ᨆᴺߢ޽ࠅ㧘ฎߊ߆ࠄ㧘㖸ჿߩჿ⚉ಽᨆߥߤߩାภಣ
ℂߩಽ㊁ߢ↪޿ࠄࠇߡ޿ࠆᚻᴺ 10,11)ߢ޽ࠆ㧚ࠝࠪࡠࠬࠦ࡯ࡊ
߆ࠄᓧࠄࠇࠆ㔌ᢔାภߩࠨࡦࡊ࡝ࡦࠣ๟ᵄᢙ㧔ࠨࡦࡊ࡞ㅦ
ᐲ㧕ࠍ f s [Hz] 㧔[ࠨࡦࡊ࡞/s]㧕ߣߔࠆߣ㧘ࠨࡦࡊ࡝ࡦࠣቯℂࠃࠅ㧘ߎߩ㔌ᢔାภߦ฽߹ࠇࠆ๟ᵄᢙᚑಽߩ਄㒢ߪ㧘

f max d f s / 2 ߢ޽ࠆ㧚ߎߩᤨ㧘ࠬࡍࠢ࠻ࡠࠣ࡜ࡓߩ๟ᵄᢙ
ಽ⸃⢻ 'f [Hz]ߪ㧘FFT ࠍⴕ߁㓙ߩಽᨆ⓹ߩࠨࡦࡊ࡞ᢙࠍ N[ࠨࡦࡊ࡞]ߣߔࠆߣ㧘 'ff s / N ߢ␜ߐࠇࠆ㧚߹ߚ㧘ߎߩN[ࠨࡦࡊ࡞]ߩಽᨆࡈ࡟࡯ࡓߩᤨ㑆㐳ߪ㧘 T N / f s ߣߥࠆ㧚ᓥߞߡ㧘๟ᵄᢙಽ⸃⢻ࠍ㜞߼ࠆߚ߼ߦߪ N ࠍᄢ߈ߊߔࠆᔅⷐ

118 (36)

313

2007

Amplitude

Current [A]500400300Target waveform

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1000Time
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0200300

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̖(a) Discharge current

䎆20

̖ Frame shift
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500

Amplitude

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SampleHanning window
Sample

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Time [ns](c) Spectrogram࿑ 9 ࠬࡍࠢ࠻࡞ߣࠬࡍࠢ࠻ࡠࠣ࡜ࡓߩ଀
Fig.9 Example of spectrum and spectrogram of discharge current.

߇޽ࠆ߇㧘N ࠍᄢ߈ߊߔࠆߎߣߦࠃࠅಽᨆࡈ࡟࡯ࡓߩᤨ㑆㐳T ߇ᄢ߈ߊߥࠅ㧘ᤨ㑆ಽ⸃⢻ߪૐਅߔࠆ㧚ߘߩߚ߼੹࿁ߪ㧘

Amplitude

Frequency [MHz]Framing㧔Repeat㧕40

SampleSpectrum

Conversion from value to color
Frequencyߦਈ߃ࠆಽᨆࡈ࡟࡯ࡓNߪᚲᦸߩ๟ᵄᢙಽ⸃⢻߇ᓧࠄࠇࠆ⒟ߥಽᨆኻ⽎࠺࡯࠲ N’ࠨࡦࡊ࡞(N>N’)ࠍࡂ࠾ࡦࠣ⓹ࠍਸ਼ߓߚ(Zero padding)Frequency⋧෻ߔࠆᤨ㑆ಽ⸃⢻ߣ๟ᵄᢙಽ⸃⢻ࠍਔ┙ߐߖࠆߚ߼㧘FFTᐲߦᄢ߈ߊ⏕଻ߒ㧘ߘߩಽᨆࡈ࡟࡯ࡓߩవ㗡ߦታ㓙ߩዪᚲ⊛

Analysis frame (N samples)

FFT
Amplitude

Amplitude [dB]8060Spectrogramᓟߦઍ౉ߒ㧘ߘߩᱷࠅᓟඨㇱಽߦ 0 ߩ୯ࠍઍ౉ߒ㧘ᤨ㑆ಽ⸃⢻ࠍ⛽ᜬߒߚ਄ߢ㧘ᡆૃ⊛ߦ๟ᵄᢙಽ⸃⢻ࠍะ਄ߐߖߚ㧚࿑ 10 ࠬࡍࠢ࠻ࡠࠣ࡜ࡓߩ૞ᚑᚻ㗅Fig.10 Method of spectrogram analysis.

ߥ߅㧘੹࿁ߩታ㛎ߦࠃࠆ᷹ቯ࠺࡯࠲ߪ 5GS/s ߥߩߢ㧘FFTߢಽᨆߢ߈ࠆ๟ᵄᢙ▸࿐ߪ㧘DC㨪2.5GHz ߣߥࠆ㧚ߒ߆ߒ㧘Timeࠝࠪࡠࠬࠦ࡯ࡊߩࠕ࠽ࡠࠣᏪၞ߇ 500MHz ߢ޽ࠆߩߢ㧘DC಴ജߔࠆ㧚ߎߩ㓙ߩၮḰ୯㧔0dB㧕ߪ㧘ಽᨆ⓹ߩ⒳㘃߿ᤨ㑆㨪500MHz ߩ๟ᵄᢙᚑಽࠍ⹦⚦ߦಽᨆߔࠆ㧚ߘߩߚ߼㧘๟ᵄ㐳㧘⸘▚ᣇᴺߦࠃࠅᄌൻߔࠆߚ߼㧘⛘ኻ⊛ߥၮḰߢߪߥ޿㧚ᢙಽ⸃⢻ࠍఝవߒ㧘FFT ࠍⴕ߁㓙ߩಽᨆࡈ࡟࡯ࡓ N ࠍ 16384ߒ߆ߒ㧘੹࿁ߩࠬࡍࠢ࠻ࡠࠣ࡜ࡓಽᨆߢߪ㧘ಽᨆో૕ߦࠊߚࠨࡦࡊ࡞
㧔3.28Ǵs㧕㧘ಽᨆኻ⽎࠺࡯࠲N’ࠍ512 ࠨࡦࡊ࡞㧔102ns㧕ࠅห⒳ߩ৻ቯᤨ㑆㐳ߩ⓹ࠍ⛔৻ߒߡ↪޿ߡ๟ᵄᢙ⸃ᨆࠍⴕߦ⸳ቯߒ㧘๟ᵄᢙಽ⸃⢻ 0.3MHz ߢಽᨆࠍⴕߞߚ㧚߹ߚ㧘ᤨߞߡ޿ࠆߚ߼㧘ฦ᡼㔚㔚ᵹᵄᒻ߆ࠄᓧࠄࠇࠆࠬࡍࠢ࠻ࡠࠣ࡜㑆ಽ⸃⢻ߪ㧘ಽᨆࡈ࡟࡯ࡓ㐳ߦട߃ߡ㧘ಽᨆࡈ࡟࡯ࡓߩࠪࡈࡓߩ⚿ᨐ߇⋥ធᲧセߢ߈ࠆ㧚ߚߣ߃߫㧘ಽᨆߔࠆᵄᒻߩᝄ᏷

࠻㊂ߦ߽ᓇ㗀ࠍฃߌࠆߚ߼㧘ߎߩಽᨆࡈ࡟࡯ࡓߩࠪࡈ࠻㊂ߪ

߇ 10 ୚⇣ߥࠆ႐ว㧘ࠬࡍࠢ࠻ࡠࠣ࡜ࡓߩ಴ജ୯ߪ 20dB ߩᏅಽᨆኻ⽎࠺࡯࠲㐳 N’ߩ 1/5 ߣߥࠆ 102 ࠨࡦࡊ࡞㧔2.4ns㧕ߣߒߣߒߡ⃻ࠇࠆ㧚߹ߚ㧘ࠬࡍࠢ࠻ࡠࠣ࡜ࡓߪ㧘ฦ๟ᵄᢙ㧘ฦᤨ

ߡ MATLAB ߦߡࡊࡠࠣ࡜ࡓࠍ૞ᚑߒ㧘ಽᨆࠍⴕߞߚ㧚㑆૏⟎ߢߩ᡼㔚㔚⩄㊂ߩ⋧ኻ⊛ߥಽᏓࠍ␜ߒߡ޿ࠆߣ߽޿ߎߩࠬࡍࠢ࠻ࡠࠣ࡜ࡓಽᨆߦࠃࠆỚ᷆㧘ߔߥࠊߜኻᢙᝄ᏷୯ߪ㧘⋧ኻ⊛ߥ߽ߩߢ޽ࠆߚ߼㧘৻⥸⊛ߦߪන૏ dB ߣߒߡ߃ࠆ㧚