This proposal addresses an opportunity for the Navy to establish an integrated business and technical strategy to provide an Open Systems active array technology for emerging Naval radar and EW systems, and for modernization/sustainment of existing systems at lower cost. Transmit/ Receive (T/R) modules typically comprise 50 to 70% of the array acquisition costs which itself represents 60 to 80% of a radar system cost. The cost reduction benefits of applying an Open approach for these distributed units are substantial. Our prior work indicates T/R Unit production costs will be reduced on the order of 50% while active array operation and maintenance costs, which are ultimately even more significant, can be reduced by greater than 50%. MMCC, together with Saab Sensis, will develop GaN power amplifier open T/R unit designs tailored for USN radar and EW systems such as AMDR. The proposed design employs cost-effective commercially sourced multi-layer circuit board populated with open foundry and commercially supplied MMICs, assembled using industry standard processes. The overall objective is to realize designs having affordable Life Cycle Costs3 to 5 times less than that of traditional approaches.