Title :
A waveguide mode-converter feed for a 5-W, 34-GHz grid amplifier
Author :
Chun-Tung Cheung ; Hacker, J.B. ; Nagy, G. ; Rutledge, D.B.
Author_Institution :
California Inst. of Technol., Pasadena, CA, USA
Abstract :
We have demonstrated a compact waveguide mode converter that excites a combination of TE/sub 10/ and TE/sub 30/ modes for feeding a grid amplifier. The length of the mode converter is only 13 mm. The effective transmitter power (ETP) at 34 GHz is 5 W, with a gain of 5.5 dB and a power-added efficiency (PAE) of 21%. The supply voltage is 3 V, with a bias current of 5.6 A. These results are comparable to those reported earlier for the same grid-amplifier design measured in free space. A spurious oscillation with a broad radiation pattern was observed at 33.6 GHz with an effective isotropic radiated power (EIRP) of 23 mW. This oscillation was suppressed when the grid was operating at high power levels, and disappeared entirely at output powers above 4.5 W.
Keywords :
millimetre wave amplifiers; waveguide components; 13 mm; 21 percent; 3 V; 34 GHz; 5 W; 5.5 dB; 5.6 A; effective isotropic radiated power; effective transmitter power; gain; grid amplifier; power added efficiency; quasi-optical amplifier; radiation pattern; spurious oscillation; waveguide mode converter feed; Circuits; Extraterrestrial measurements; Feeds; Millimeter wave measurements; Minimization; Power amplifiers; Power generation; Rectangular waveguides; Thermal conductivity; Voltage;
Conference_Titel :
Microwave Symposium Digest, 2002 IEEE MTT-S International
Conference_Location :
Seattle, WA, USA
Print_ISBN :
0-7803-7239-5
DOI :
10.1109/MWSYM.2002.1012145
