A 50:1 Bandwidth GaAs MMIC Phase Shifter

We present here some new results obtained with a high-frequency, ultrawide-band, analog phase shifter. Our phase shifting scheme uses an original vector processing architecture, including a phase sequence filter generating a 4 orthogonal vectors pseudo-basis set: {±I,±Q}. This architecture has been implemented into a GaAs MMIC 0.1-¿m PHEMT technology (1500 ¿m × 2000 ¿m). Network analyzer measurements indicate a 50:1 operational bandwidth at ¿3 dB and 360° phase variation capability over a decade bandwidth, in good agreement with simulated results. High-precision digitally-operated {±I,±Q} discrete phase steps over a decade bandwidth have been obtained. With further design adaptation and architecture integration, preliminary performances demonstrated here are expected to be attractive for multistandard communication systems.