Aspects of the subject disclosure may include, for example, a coupling device includes a circuit that receives a signal. At least one passive electrical circuit element generates an electromagnetic field in response to the signal. A portion of the electromagnetic field is guided by a surface of a transmission medium to propagate as a guided electromagnetic wave longitudinally along the transmission medium. Other embodiments are disclosed.

Aspects of the subject disclosure may include, for example, a coupling device includes a circuit that receives a signal. At least one passive electrical circuit element generates an electromagnetic field in response to the signal. A portion of the electromagnetic field is guided by a surface of a transmission medium to propagate as a guided electromagnetic wave longitudinally along the transmission medium. Other embodiments are disclosed.

Methods and apparatus for providing adaptive grounding in mixed-signal electronic dies, circuits, modules, or other devices. In one example a module in which adaptive grounding is implemented includes a substrate having disposed thereon a plurality of signal contacts and a ground connection, and a mixed-signal die disposed on the substrate and including a signal section and a control section, the signal section having a plurality of radio frequency components each connected to a respective one of the plurality of signal contacts on the substrate by a corresponding signal connector, and the control section having at least two ground paths that selectively connect the control section to the ground connection on the substrate and which are physically spaced apart from one another, the mixed-signal die further including at least two switches, each operable to selectively connect one of the ground paths to the ground connection.

Methods and apparatus for providing adaptive grounding in mixed-signal electronic dies, circuits, modules, or other devices. In one example a module in which adaptive grounding is implemented includes a substrate having disposed thereon a plurality of signal contacts and a ground connection, and a mixed-signal die disposed on the substrate and including a signal section and a control section, the signal section having a plurality of radio frequency components each connected to a respective one of the plurality of signal contacts on the substrate by a corresponding signal connector, and the control section having at least two ground paths that selectively connect the control section to the ground connection on the substrate and which are physically spaced apart from one another, the mixed-signal die further including at least two switches, each operable to selectively connect one of the ground paths to the ground connection.

Aspects of the subject disclosure may include, a system that obtains a group of signals that are each representative of a corresponding one of a group of electromagnetic waves, analyzes the group of signals to determine signal characteristics, and determines, according to the signal characteristics, predicted characteristics for a communication signal that is to be transmitted by a circuit. Other embodiments are disclosed.

A high-frequency transmission element is provided. The high-frequency transmission element includes a connecting wire structure and an impedance matching plate structure. The connecting wire structure includes a connecting wire and a connecting pad. The connecting pad is located at an end of the connecting wire. The impedance matching plate structure includes an impedance matching plate body, an opening, and an impedance matching portion. The connecting pad is located in a projection range of the opening in a direction of orthographic projection of the impedance matching plate structure. The impedance matching portion is located in a periphery of the opening and extends in the direction from the connecting wire towards the connecting pad.

A high-frequency transmission element is provided. The high-frequency transmission element includes a connecting wire structure and an impedance matching plate structure. The connecting wire structure includes a connecting wire and a connecting pad. The connecting pad is located at an end of the connecting wire. The impedance matching plate structure includes an impedance matching plate body, an opening, and an impedance matching portion. The connecting pad is located in a projection range of the opening in a direction of orthographic projection of the impedance matching plate structure. The impedance matching portion is located in a periphery of the opening and extends in the direction from the connecting wire towards the connecting pad.

An impedance matching device includes a first dielectric substrate; a first transmission line circuit; a first conductive pad which extends toward the first transmission line circuit on the first dielectric substrate to at least partially vertically overlap the first transmission line circuit: a first reference potential layer; and a first matching load which is electrically connected to the first conductive pad and has a first resistance. An area where the first conductive pad vertically overlaps the first transmission line circuit has a size configured such that a load reactance associated with the first transmission line circuit is equal to or less than a predetermined threshold and an absolute value of a difference between a load resistance associated with the first transmission line circuit and the first resistance is equal to or less than a predetermined resistance threshold.

An impedance matching device includes a first dielectric substrate; a first transmission line circuit; a first conductive pad which extends toward the first transmission line circuit on the first dielectric substrate to at least partially vertically overlap the first transmission line circuit: a first reference potential layer; and a first matching load which is electrically connected to the first conductive pad and has a first resistance. An area where the first conductive pad vertically overlaps the first transmission line circuit has a size configured such that a load reactance associated with the first transmission line circuit is equal to or less than a predetermined threshold and an absolute value of a difference between a load resistance associated with the first transmission line circuit and the first resistance is equal to or less than a predetermined resistance threshold.

The planar Balun of the present invention can be used in various hundred to and thousand-watt level push-pull power amplifiers, which can greatly reduce the area and the amount of second harmonics of the power amplifier, and improve the flexibility of circuit layout and spectral purity, especially at high frequencies, such as around 915 MHz, and can replace the widely used coaxial Balun to simplify amplifier design.