Systems and methods relating to patch antennas and signal combiner circuits. The invention relates to a circuit with discrete capacitors, inductors and amplifiers arrayed in an arrangement with 2 input ports and one output port. The circuit provides a high degree of reverse electrical isolation between the input ports and the output at the radio frequency. The circuit provides an output that is the vector sum of signals present at the first and second input ports. The circuit additionally provides for introduction of a 90 degree phase shift into either of the two inputs. This circuit can be used with dual feed patch antennas.