Open AccessPulsed gate bias control of GaN HEMTs to improve pulse‐to‐pulse stability in radar applications
Author(s) -
Delprato J.,
Delias A.,
Medrel P.,
Barataud D.,
Campovecchio M.,
Neveux G.,
Martin A.,
Bouysse P.,
Nebus J.M.,
Tolant C.,
Eudeline P.
Publication year - 2015
Publication title -
electronics letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.375
H-Index - 146
ISSN - 1350-911X
DOI - 10.1049/el.2015.1052
Subject(s) - pulse (music) , amplifier , high electron mobility transistor , materials science , optoelectronics , pulse width modulation , rf power amplifier , transistor , bandwidth limited pulse , radar , pulse amplitude modulation , amplitude , power (physics) , optics , electrical engineering , physics , telecommunications , ultrashort pulse , computer science , engineering , voltage , detector , cmos , laser , quantum mechanics
A significant improvement is demonstrated in the measured pulse‐to‐pulse stability of an S‐band 6 W GaN high electron mobility transistor (HEMT) power amplifier by generating an appropriate pulse of the gate bias and thus a warm‐up drain current just before each radio‐frequency (RF) pulse of a periodic and coherent radar burst. The amplitude and the width of this gate bias pulse preceding each periodic RF pulse of the burst are experimentally varied to investigate the trade‐off between the improvement of pulse‐to‐pulse stability and the total power‐added efficiency. Finally, this technique of synchronised warm‐up gate bias pulse demonstrated a 10 dB improvement of measured amplitude pulse‐to‐pulse stabilities to meet the critical stability requirement below −55 dB for the RF power amplifier.