Kenichi TAJIMA


A 0.3-to-5.5 GHz Digital Frequency Discriminator IC with Time to Digital Converter and Edge Counter for Instantaneous Frequency Measurement
Akihito HIRAI Koji TSUTSUMI Hideyuki NAKAMIZO Eiji TANIGUCHI Kenichi TAJIMA Kazutomi MORI Masaomi TSURU Mitsuhiro SHIMOZAWA 
Publication:   
Publication Date: 2019/07/01
Vol. E102-C  No. 7  pp. 547-557
Type of Manuscript:  Special Section PAPER (Special Section on Analog Circuits and Their Application Technologies)
Category: 
Keyword: 
digital frequency discriminator (DFD)instantaneous frequency measurement (IFM)time-to-digital converter (TDC)multiphase clock
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A Compact RF Frontend Module of Active Phased Array Antenna for High SHF Wideband Massive MIMO in 5G
Hideyuki NAKAMIZO Shintaro SHINJO Koji TSUTSUMI Satoshi YAMAGUCHI Hideharu YOSHIOKA Akihiro OKAZAKI Akinori TAIRA Kenichi TAJIMA 
Publication:   
Publication Date: 2017/10/01
Vol. E100-C  No. 10  pp. 818-824
Type of Manuscript:  INVITED PAPER (Special Section on Microwave and Millimeter-Wave Technology)
Category: 
Keyword: 
massive MIMOactive phased array antennahigh SHFRF frontend5G
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Parallel Dual Modulus Prescaler with a Step Size of 0.5
Hideyuki NAKAMIZO Kenichi TAJIMA Ryoji HAYASHI Kenji KAWAKAMI Toshiya UOZUMI 
Publication:   IEICE TRANSACTIONS on Electronics
Publication Date: 2012/07/01
Vol. E95-C  No. 7  pp. 1189-1194
Type of Manuscript:  Special Section PAPER (Special Section on Recent Trends of Microwave Systems and Their Fundamental Technologies)
Category: 
Keyword: 
phase locked loopsdividerphase noisefractional-N frequency synthesizerdual modulus prescaler
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A Novel Spur Suppression Technique Using Three-Phase Holding Pulse for High-Frequency-Output Direct Digital Synthesizer
Kenichi TAJIMA Ryoji HAYASHI 
Publication:   IEICE TRANSACTIONS on Electronics
Publication Date: 2010/07/01
Vol. E93-C  No. 7  pp. 1014-1021
Type of Manuscript:  Special Section PAPER (Special Section on Recent Progress in Microwave and Millimeter-Wave Technologies)
Category: 
Keyword: 
direct digital synthesizerholding pulsedigital analog converter
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Novel Phase-Continuous Frequency Hopping Control for a Direct Frequency Synthesizer Using a Quadrature Mixer Driven by Two DDSs
Kenichi TAJIMA Ryoji HAYASHI Kenji ITOH Yoji ISOTA 
Publication:   IEICE TRANSACTIONS on Electronics
Publication Date: 2006/12/01
Vol. E89-C  No. 12  pp. 1829-1835
Type of Manuscript:  Special Section PAPER (Special Section on Emerging Microwave Techniques)
Category: Active Circuits/Devices/Monolithic Microwave Integrated Circuits
Keyword: 
frequency synthesizerdirect digital synthesizerquadrature mixerphase accumulatoroverflowphase
 Summary | Full Text:PDF