The disclosure relates to a hybrid orthogonal signal generator, a coil transmission front-end device, an RF coil system, and an MRI system. The hybrid orthogonal signal generator has an input end for receiving an RF signal, generates a hybrid orthogonal excitation signal on the basis of the RF signal, and provides the hybrid orthogonal excitation signal by means of an output end of the hybrid orthogonal signal generator, and comprises: a first conductor, arranged in a plane and being arc-shaped; and a second conductor having mutual inductance with the first conductor, the second conductor being connected between the input end and output end, wherein the first conductor and second conductor are parallel and arranged as mirror images of each other. The hybrid orthogonal signal generator has a compact size and is suitable for providing hybrid orthogonal excitation signals for an MRI system with a low field strength.

An electromagnetic coupler includes a dielectric layer with a first transmission line connecting an input port to an output port. A second transmission line on another surface of the dielectric layer forms a coupled port and an isolation port. The electromagnetic coupler provides a coupled signal at the coupled port, which is representative of an input signal at the input port. The amplitude of the coupled signal is related to the amplitude of the input signal by a coupling factor. A tuning element on the dielectric layer is configured to stabilize the coupling factor over a range of variations in thickness of the dielectric layer.

A coupler is presented that has high-directivity and low coupling coefficient variation. The coupler includes a first trace with a first edge substantially parallel to a second edge and substantially equal in length to the second edge. The first trace includes a third edge substantially parallel to a fourth edge. The fourth edge is divided into three segments. The outer segments are a first distance from the third edge. The middle segment is a second distance from the third edge. Further, the coupler includes a second trace, which includes a first edge substantially parallel to a second edge and substantially equal in length to the second edge. The second trace includes a third edge substantially parallel to a fourth edge. The fourth edge is divided into three segments. The outer segments are a first distance from the third edge. The middle segment is a second distance from the third edge.

The isolated port of a 0/90 degree coupler is terminated by a novel complex termination impedance circuit having a reactance. The absolute value of the reactance is at least two ohms. The coupler receives a signal on its input port, and outputs a first signal on its first output port and a second signal on its second output port. A first load is coupled to the first output port without an intervening matching network. A substantial impedance mismatch exists between the first output port and the first load. A second load is coupled to the second output port without an intervening matching network. A substantial impedance mismatch exists between the second output port and the second load. Despite the substantial impedance mismatches, the first and second signals have a phase difference in a range of from 88 degrees to 92 degrees while exhibiting an amplitude imbalance less than 2 dB.

The present disclosure relates to a coupler and a base station antenna. The coupler comprises: a first coupling member comprising a first substrate, and a first signal path and a first sub-path of a second signal path located on the first substrate, the first sub-path configured to be at least partially coupled with the first signal path to couple a portion of a signal in the first signal path into the second signal path; a second coupling member vertically stacked with the first coupling member, the second coupling member comprising a second substrate, and a second sub-path of the second signal path located on the second substrate; a shielding member disposed between the first substrate and the second substrate so as to shield the first coupling member and the second coupling member from one another, the shielding member being provided with a first connection through-hole; and a first connection member passing through the first connection through-hole and electrically connected between the first sub-path and the second sub-path.

Devices and methods related to directional couplers. In some implementations, a coupler can include a driver arm and a coupler arm implemented relative to the driver arm to detect power of an RF signal. Portions of the driver and coupler arms can form an overlapping region, with at least one of the driver and coupler arms having a non-straight arm shape. The overlapping region can include a non-zero lateral offset between the driver and coupler arms. In some implementations, a coupler can include a driver arm having input and output sides, and a coupler arm having input and output sides and implemented relative to the driver arm to detect power of an RF signal. The coupler can further include a phase-shifting feature implemented with respect to at least one of the driver and coupler arms to reduce phase difference of power ripples associated with the coupler.

Tunable, broadband directional coupler circuits employing one or more additional, switchable coupling circuits for controlling frequency response, and related methods. In exemplary aspects, the directional coupler includes one or more additional coupling circuits that each include an additional coupling line located adjacent to the primary coupling line and that can be selectively activated to change a frequency response of the directional coupler. When an additional coupling circuit is activated, its additional coupling line has the effect of extending the length of the primary coupling line through mutual inductance, thus changing the coupling frequency response of the directional coupler. The additional coupling circuit includes one or more switch(es) to allow for the selective coupling of its additional coupling line to the coupling and/or isolation ports of the directional coupler to selectively change and control the frequency response of the primary coupling line.

A power divider/combiner includes a first transmission line that includes a first part and a second part, and a second transmission line and a third transmission line that are electromagnetically coupled with the first transmission line. The first part, the second part, the second transmission line and the third transmission line are each of a particular length. The first part, the second transmission line and the third transmission line are respectively connected to a first port, a second port and a third port for inputting/outputting signals having a target wavelength equal to four times the particular length.

A coupling element is disclosed, comprising four coils that are arranged such that each one of the coils extends both in a first layer and a second layer. The first layer and the second layer are stacked with respect to each other and separated by an intermediate dielectric layer. The layout of each layer is configured to provide a transformer coupling between a first one and a third one of the coils, and between a second one and a fourth one of the coils. Further, the first coil and the second coil, and the third coil and the fourth coil, respectively, are routed so as to allow a differential signaling. A semiconductor device and a differential hybrid coupler comprising the coupling element are also disclosed.

A directional coupler including at least two coupled lines and at least three ports is disclosed. A first coupled line of the at least two coupled lines includes at least two ports such as an input port and an output port. A second coupled line of the at least two coupled lines includes a forward path and a backward path that are joined together at a third port to form a loop. To achieve a constant coupling attenuation over a broad frequency band and to minimize dimensions, the second coupled line includes a higher line impedance than the first coupled line, at least two times higher, and a coupling resistor is connected in series either in the forward path or in the backward path. In a multichannel power splitter, directional couplers are arranged in series with one another.