Presentation 2003/10/17
A Mini-TWT Array for Array-fed Reflector Antenna in 21GHz-band Broadcasting Satellites(Component & Antenna)
Masashi Kamei, Hitoshi Nakagawa, Kazuyoshi Shogen, Toshihiro Nomoto,
PDF Download Page PDF download Page Link
Abstract(in Japanese) (See Japanese page)
Abstract(in English) Broadcasting satellite services with a high sense of reality, such as ultra-high definition television (UDTV) and three-dimensional television are expected to be delivered using the frequency band from 21.4 to 22.0 GHz. One of the major technical difficulties in using this frequency band is to overcome large rain attenuation. By using the array antenna technique, in which the radiation pattern can be changed adaptively to transmit high e.i.r.p. only in heavy rain areas while the e.i.r.p. for the rest of the service area remains low, required satellite payload power can be reduced. A prototype mini-TWT array for an array-fed reflector antenna in a 21GHz-band broadcasting satellite was manufactured. Seven mini-TWTs, spaced at a distance corresponds to 1.5 wavelengths at 22.0 GHz, were aligned in a two-dimensional array. The cross-sectional dimensions of each mini-TWT were 15.3 mm x 20.0 mm. Flat heat pipes were mounted between adjacent mini-TWTs to provide sufficient heat transfer for the mini-TWTs located closely. Moreover, thin magnetic shields were applied around each mini-TWT so that leakage of the magnetic fields of neighboring mini-TWTs, which might influence the electron beam focusing, could be reduced. We have confirmed that the performance of the central mini-TWT of this array structure is almost same as that of an isolated mini-TWT.
Keyword(in Japanese) (See Japanese page)
Keyword(in English) Traveling wave tube / 21GHz-band broadcasting satellite / Array antenna / TWT array / Heat pipe
Paper # SAT2003-130
Date of Issue

Conference Information
Committee SAT
Conference Date 2003/10/17(1days)
Place (in Japanese) (See Japanese page)
Place (in English)
Topics (in Japanese) (See Japanese page)
Topics (in English)
Chair
Vice Chair
Secretary
Assistant

Paper Information
Registration To Satellite Telecommunications (SAT)
Language ENG
Title (in Japanese) (See Japanese page)
Sub Title (in Japanese) (See Japanese page)
Title (in English) A Mini-TWT Array for Array-fed Reflector Antenna in 21GHz-band Broadcasting Satellites(Component & Antenna)
Sub Title (in English)
Keyword(1) Traveling wave tube
Keyword(2) 21GHz-band broadcasting satellite
Keyword(3) Array antenna
Keyword(4) TWT array
Keyword(5) Heat pipe
1st Author's Name Masashi Kamei
1st Author's Affiliation NHK Science and Technical Research Laboratories()
2nd Author's Name Hitoshi Nakagawa
2nd Author's Affiliation Broadcasting Satellite System Corporation
3rd Author's Name Kazuyoshi Shogen
3rd Author's Affiliation NHK Science and Technical Research Laboratories
4th Author's Name Toshihiro Nomoto
4th Author's Affiliation NHK Science and Technical Research Laboratories
Date 2003/10/17
Paper # SAT2003-130
Volume (vol) vol.103
Number (no) 386
Page pp.pp.-
#Pages 6
Date of Issue