Abstract: A balanced hybrid coupler comprising four identical pairs of quarter wavelength parallel coupled lines, 45A, 45B and 46A, 46B a first input port, a second input port, a first output port and a second output port. The first input port comprising a pair of signal carrying terminals 41A, 41B, the second input port comprising a pair of signal carrying terminals 42A, 42B, the first output port comprising a pair of signal carrying terminals 43A, 43B, and the second output port comprising a pair of signal carrying terminals 44A, 44B. A wiring section 49 connects quarter wavelength coupled line pairs 45A and 45B to quarter wavelength coupled line pairs 46A and 46B, and includes a first balanced connection comprising a pair of connection lines 47A, 47B and a second balanced connection comprising connecting lines 48A, 48B.

Abstract: A multilayer 180 degree hybrid coupler comprises a cascaded pair of quarter wavelength directional couplers, one of the connections between the directional couplers being made by direct connection and the other connection being made indirectly via a length of transmission line that introduces a 180 degree phase shift at the operating frequency of the hybrid coupler. Each directional coupler comprises a pair of broadside coupled conductive tracks on opposite sides of a dielectric layer and the length of transmission line comprises a further conductive track on at least one side of the dielectric layer. Both the direct connection and the connection via the length of transmission line extend through the dielectric layer at respective via holes so that the hybrid coupler has two input ports on one side of the dielectric layer and two output ports on the other side of the dielectric layer.

Abstract: A substrate for mounting a device is disclosed. The substrate includes at least one transition for providing an RF connection to a lead of the device, the lead extending from a device input to an otherwise free end. The transition comprises two spaced apart electrically coupled members, the first member occupying at least the same area on a top surface of the substrate as the device lead to which it is to connect, and the second member lying in register with the first member. The transition comprises an input, which is located at the end of the second member which is nearest the free end of the device lead and an output which is located at the opposite end of the first member and which is in register with the device input. The electrical characteristics of the transition are such that the electrical length from the input of the transition to the output of the transition is approximately equal to one half of a wavelength over a given operating frequency band of the device.

Abstract: A multilayer 180 degree hybrid coupler comprises a cascaded pair of quarter wavelength directional couplers 16a/16b and 18a/18b, one of the connections between the directional couplers being made by direct connection and the other connection being made indirectly via a length of transmission line 22 that introduces a 180 degree phase shift at the operating frequency of the hybrid coupler. Each directional coupler comprises a pair of broadside coupled conductive tracks on opposite sides of a dielectric layer and the length of transmission line 22 comprises a further conductive track on at least one side of the dielectric layer. Both the direct connection and the connection via the length of transmission line 22 extend through the dielectric layer at respective via holes 40, 42 so that the hybrid coupler has two input ports 1, 3 on one side of the dielectric layer and two output ports 2, 4 on the other side of the dielectric layer.

Abstract: A substrate for mounting a device is disclosed. The substrate includes at least one transition for providing an RF connection to a lead of the device, the lead extending from a device input to an otherwise free end. The transition comprises two spaced apart electrically coupled members, the first member occupying at least the same area on a top surface of the substrate as the device lead to which it is to connect, and the second member lying in register with the first member. The transition comprises an input, which is located at the end of the second member which is nearest the free end of the device lead and an output which is located at the opposite end of the first member and which is in register with the device input. The electrical characteristics of the transition are such that the electrical length from the input of the transition to the output of the transition is approximately equal to one half of a wavelength over a given operating frequency band of the device.