120-W Ku-Band GaN SSPA with Diode Linearizer for Future Broadcasting Satellites

Masafumi NAGASAKA  Masaaki KOJIMA  Takuma TORII  Hiromitsu UTSUMI  Koji YAMANAKA  Shintaro SHINJO  Mitsuhiro SHIMOZAWA  Hisashi SUJIKAI  

IEICE TRANSACTIONS on Electronics   Vol.E102-C   No.10   pp.717-724
Publication Date: 2019/10/01
Online ISSN: 1745-1353
DOI: 10.1587/transele.2019MMP0006
Type of Manuscript: Special Section PAPER (Special Section on Microwave and Millimeter-Wave Technologies)
broadcasting satellite,  SSPA,  Ku-band,  GaN,  

Full Text: FreePDF

Satellite broadcasting of 4K/8K ultra-high definition television (UHDTV) was launched in Japan in December 2018. Because this system uses the amplitude and phase shift keying (APSK) modulation scheme, there is a need to improve the non-linear characteristics of the satellite transponders. To meet this requirement, we have been developing a 120-W-class Ku-band solid state power amplifier (SSPA) as a replacement for the currently used traveling wave tube amplifier (TWTA). In this study, we developed a gallium-nitride (GaN) SSPA and linearizer (LNZ). The SSPA achieved an output power of 120W while maintaining a power added efficiency (PAE) of 31%. We evaluated the transmission performance of 16APSK in this SSPA channel in comparison with that in the TWTA channel.