Design of T/R module for the wideband active array antenna

In this paper, a wideband sub-array module which has 4-channel T/R modules was built and evaluated. The T/R module has 5-bit digital MMIC phase shifter, attenuator, amplifiers, Wilkinson power dividers, etc. Two absorptive matching equalizers to get uniform gain over multi-octave bandwidth are inserted in the common part of the module. Chip-on-substrate technology was introduced to get the repeatability for the packaging of MMIC chips. To eliminate the cavity resonance of the module housing, the absorbing material is attached on the housing. Two types of the sub-array modules were built for the interface with the planar triangular array lattice. These modules are attached to a cold plate to remove the heat of the power amplifiers in the module