| The design of microwave/millimeter wave active arrays is investigated using a multilayered packaging architecture. The goal of the packaging technique is to utilize multichip module (MCM) technologies which offer the advantages of lower cost, higher reliability and yield. The challenge of using these technologies for constructing arrays is achieving efficient and stable operation with substrate characteristics that are not ideal for conventional microstrip antennas.; Several novel circuit elements are studied that allow efficient and stable operation of microwave/millimeter wave active arrays. Measurements demonstrate that high radiation efficiency is possible with the cavity backed patch. Approximate and full-wave models are developed for the cavity backed patch and several similar related antennas. Novel use of the open end stub, found in many electromagnetic coupled antennas, is found to lead to enhanced bandwidth and circular polarization performance. The RF via is presented with an equivalent circuit model and provides a compact, efficient and isolated transition between layers. Finally, monolithic microwave integrated circuit (MMIC) amplifiers are placed in individual cavities that provide isolation from other circuit elements and allow placement of the device directly on the thermal carrier.; The application of spatial power combining is used as a demonstration of the packaging approach, the modeling of the circuit elements and achieving desired array characteristics. Design procedures for achieving high combining efficiency arrays and calculating the radiated power are presented. Two single element active antennas and two 4 x 4 arrays will be presented, demonstrating the highest reported combining efficiency to date, with accurate calculated predictions. |
