RF-wafer scale integration: a new approach to active phased arrays

Active phased array antennas utilize individually packaged transmit/receive modules, which provide both transmitter and receiver functions on λ2 wavelength centers. Such modules usually contain 5 to 7 individual GaAs circuits which provide the following functions: transmit amplifier, phase shifter, variable attenuator, T/R switch, and low noise amplifier. The authors describe ongoing efforts in which many T/R modules are fabricated simultaneously on a single 3-inch GaAs-wafer. Redundancy in circuit elements is utilized to obtain high yield. The resulting wafer of GaAs T/R cells is utilized as a layer within a more complex package that includes the individual radiating element. Efforts to date have focused on technology for 2-20 GHz and upon extending the technology to higher frequencies