CONSTRAINTS IN THE DESIGN OF GALLIUM-ARSENIDE MESFET MMIC DISTRIBUTED AMPLIFIERS (MICROWAVE, MONALYTHIC, TRAVELING WAVE)

In this paper, the analysis of GaAs MESFET distributed amplifiers and a systematic approach to their design are presented. The analysis focuses on fundamental design considerations and also establishes the maximum gain-bandwidth product of the amplifier. The design approach presented enables one to examine the tradeoffs between the variables, such as the device, the number of devices, the impedances and cutoff frequency of the transmission lines, and arrive at a design which gives the desired frequency response. The power output capability of the amplifier and the use of matching sections to improve amplifier frequency response are also presented. Additionally, the power generated by the individual devices within the distributed amplifier was investigated. Sensitivity analysis was employed to demonstrate the suitability of the distributed amplifier for use in integrated circuits. The theoretically predicted response has been compared to computer-aided analysis results and the theory is in good agreement. When compared to previously published data, the theory is also in good agreement.