A dual beam dual-selectable-polarization phased array antenna comprises an aperture unit, a printed wiring board, radiating elements, chip units, a pressure plate, and a rear housing unit. The printed wiring board has sub assemblies bonded to each other with a bonding material providing both mechanical and electrical connection. The printed wiring board is connected to the aperture unit. The radiating elements are formed on the printed wiring board. The chip units are mounted on the printed wiring board. The chip units include circuits capable of controlling radio frequency signals radiated by the radiating elements to form dual beams with independently selectable polarization. The pressure plate is connected to the aperture unit. The aperture unit is connected to the rear housing unit such that the aperture unit covers the rear housing unit.