Abstract: A strip-line directional coupler is provided in which the volumetric size is reduced without a reduction in electrical characteristics. The input and output coupling lines are wound into separate spirals each having the same pitch so that they can be located at a fixed distance with respect to one another which is sufficiently close along their entire length to provide coupling of an input signal from the input coupling line to the output coupling line in the backwards direction. A first and second ground plane is located one on either side of and a small distance from each spirally wound input and output coupling line. A dielectric material is located between the input and output lines and between the ground planes and the input and output lines.

Abstract: A directional coupler arrangement is provided in which a plurality of directional couplers are cascaded by connecting the thru terminal of each coupler to the input terminal of the succeeding coupler and connecting the output terminal of each coupler except the last to the forward terminal of the succeeding coupler so that the desired backward coupled signal of each of the couplers arrive simultaneously at the output terminal of the last coupler so as to be additive and thereby produce an enhanced backward coupled signal. The forward coupled signals arrive at the forward terminal of the first coupler either out of coincidence or in a subtractive mode thereby minimizing the forward coupled signal.

Abstract: A data communication system is provided in which the data handling capacity of the system is doubled. The data in the system travels on a single wire in both directions simultaneously. Each pair of terminals associated with the communication system is interfaced with the single wire by a repeater. The repeater includes first and second directional couplers for coupling data signals from the repeater to the wire in the one direction and in the opposite direction, respectively, without substantial signal interference with signals being received by the repeater on the same wire. A wrap control function is included in the repeater which allows data signals to be placed on the wire going in the opposite direction from the received signals.