Monolithic Microwave Integrated Circuit (MMIC) Beamforming Weights

This proposal is presented in response to the SBIR solicitation number AF04-215 entitled "Monolithic Microwave Integrated Circuit (MMIC) Beamforming Weights". Beamforming elements adjust both phase and amplitude of individual elements of an array antenna to provide beam pointing and nulling. In particular the SBIR calls for the development of such an element to support MILSATCOM receive arrays by eliminating current ferrite technology with MMIC technology. The desired performance over the frequency range from 43.5-45.5 GHz includes 8-bits of amplitude and 9-bits of phase adjustment with element-to-element RMS tracking of 3 Degrees and 0.3 dB. As outlined herein Hittite proposes both innovative technology and circuit techniques to address specifications. The weighting function can be achieved using both active and passive approaches. For the passive approach MHEMT and PIN switch technologies show the most promise at 44 GHz while InP HBT technologies are best suited for the active approach. Passive approaches to considered in Phase I include both digital and analog attenuator and phase shifter topologies as well as vector modulator topologies. The active approach will be focused on the implementation of a vector modulator composed of Gilbert multipliers. The best solutions will be fabricated and evaluated during the Phase II program.