Active phased array antenna systems are capable of forming one or more antenna beams of electromagnetic energy and electronically steering the beams to targets, with no mechanical moving parts involved. A phased array antenna system has many advantages over other types of mechanical antennas, such as dishes, in terms of beam steering agility and speed, low profiles, low observability, and low maintenance.
A beam forming network is a major and critical part of a phased array antenna system. The beam forming network is responsible for collecting all the electromagnetic signals from the array antenna modules and combining them in a phase coherent way for the optimum antenna performance. The element spacing in a phased array is typically at one-half of the wavelength for electromagnetic waves in space.
There are design challenges when utilizing a phased array antenna system. Firstly, it is important that the phased array include a rhombic shape of aperture for low observabilty requirements of the system. In addition, the system should be as small as possible to conserve space while still having the same performance characteristics of conventional shaped phased array antenna systems. Furthermore, as array antenna frequency increases, the element spacing decreases in an inversely proportional manner. Due to this tight spacing in phased arrays at microwave frequencies, transitions of radio frequency (RF) energy from inside of the beam forming network printed wiring board to the backside of the antenna have always been one of the critical RF design factors in phased array development. Conventional designs had tighter tolerances in the feature alignments of the RF transition, which limits the choice of suppliers for the systems and impacts the cost and schedule for producing the antennas as well.
What is needed is a method and system to overcome the above-identified issues. One or more of the present embodiments address one or more of the above-identified needs and others.
The features, functions, and advantages can be achieved independently in various embodiments of the present invention or may be combined in yet other embodiments.