Title :
Taper and forward-feed in GaAs MMIC distributed amplifiers
Author :
Ross, M. ; Harrison, R.G. ; Surridge, R.K.
Author_Institution :
Northern Telecom Ltd., St-Laurent, Que., Canada
Abstract :
The authors consider an improved distributed-amplifier (DA) architecture which uses simultaneous inductance tapering and signal forward feeding to obtain additional degrees of freedom for optimization. The effects of losses on the high-frequency performance are investigated numerically using detailed MESFET models. Further simulations show how impedance tapering, forward-feed capacitors, and series-drain inductors can be used together to overcome the high-frequency losses, thereby maximizing the bandwidth. The approach is illustrated by the design and fabrication of a DA with a predicted gain of 6.9+or-0.7 dB over a bandwidth of 1-12 GHz. The results support the use of the forward-feed concept and also validate the hypothesis that induction tapering should increase gain and improve the input and output voltage standing-wave ratios.<>
Keywords :
III-V semiconductors; MMIC; field effect integrated circuits; gallium arsenide; losses; microwave amplifiers; 1 to 12 GHz; 6.2 to 7.6 dB; GaAs; III-V semiconductors; MESFET models; MMIC distributed amplifiers; SHF; VSWR improvement; forward-feed capacitors; high-frequency performance; inductance tapering; losses; monolithic microwave IC; optimization; series-drain inductors; signal forward feeding; simulations; Bandwidth; Capacitors; Distributed amplifiers; Gallium arsenide; Impedance; Inductance; Inductors; MESFETs; MMICs; Performance loss;
Conference_Titel :
Microwave Symposium Digest, 1989., IEEE MTT-S International
Conference_Location :
Long Beach, CA, USA
DOI :
10.1109/MWSYM.1989.38900
