Stripline quadrature coupler

Abstract From the Canadian patent

The coupler accepts four independent RF input signals divides each-input into four equal parts and applies each, part to one of four adjoining output ports. Each input signal divided part is phase shifted a multiple of 90° whereby the output ports, taken in the proper order are in, phase quadrature. The novel coupler comprises four hybrid couplers all, of which are fabricated on a dielectric substrate. The hybrid couplers are located on the substrate in a unique interleaved configuration whereby intercouplings are formed between selected hybrid couplers. The interleaved construction results in the electrical length of all intercouplings being controlled and, preferably, all are the same …