Title :
An analog MMIC phase modulator for X-band satellite transponder applications
Author :
Ali, Fazal ; Mysoor, Narayan
Author_Institution :
Westinghouse Electric Corp., Baltimore, MD, USA
Abstract :
The design and measured performance of a GaAs MMIC (monolithic microwave integrated circuit) analog linear phase modulator for the next-generation space-borne communications systems are presented. The analog phase shifter is based on the reflection-type hybrid coupled approach and uses a novel lumped quadrature hybrid and MESFET varactors as a building block. Three cascaded sections (with tapered varactor sizes) of this building block along with two high-isolation amplifiers have been realized in a single chip (96 mils*36 mils). This MMIC provides an X-band (8415+or-50-MHz) phase modulation with +or-2.6 radians (300 degrees ) of peak phase deviation, +or-2% of phase deviation linearity, 1.5-dB insertion loss, and better than 12-dB input and output return loss performance.<>
Keywords :
MMIC; modulators; phase modulation; satellite relay systems; transponders; 1.5 dB; 12 dB; 8.415 GHz; GaAs; MESFET varactors; SHF; X-band; analog MMIC; analog linear phase modulator; cascaded sections; high-isolation amplifiers; hybrid coupled approach; lumped quadrature hybrid; monolithic microwave integrated circuit; reflection-type; satellite transponder applications; space-borne communications systems; tapered varactor sizes; Analog integrated circuits; Gallium arsenide; Integrated circuit measurements; MMICs; Microwave integrated circuits; Microwave measurements; Monolithic integrated circuits; Phase measurement; Phase modulation; Varactors;
Journal_Title :
Microwave and Guided Wave Letters, IEEE
