In one embodiment, an impedance matching network includes variable capacitors. A first variable capacitor has a terminal electrically connected to the RF input. A second variable capacitor has a terminal electrically connected to the RF output. At least one of the variable capacitors is an electrically variable capacitor (EVC). The EVC includes a plurality of parallel-coupled capacitors comprising fine capacitors increasing in capacitance and coarse capacitors having a greater capacitance. A capacitor position for the EVC for enabling an impedance match is determined by a processor using software. An impedance match is enabled by directly switching the electronically variable capacitor to the determined capacitor position.

A capless impedance tuner can include first node and second nodes, a first series path, a second series path, and an inductance path, each between the first node and the second node and including a switch to allow the path to couple or uncouple the first and second nodes. Each series path can be configured to allow a substantially continuous flow of a direct current between the first node and the second node when coupled. The tuner can further include a shunt path with a switch to allow coupling or uncoupling of the second node and ground. The tuner can further include a switchable grounding path implemented along the inductance path and configured to allow the inductance path to function as a series inductance path between the first and second nodes, or as a shunt inductance path between the ground and a node along the inductance path.

In a high-frequency transformer element includes a primary coil including first coil conductors and a secondary coil including second coil conductors are disposed in a multilayer body that includes a plurality of insulating layers. A magnetic-field cancellation conductor pattern is disposed in the multilayer body, is adjacent to some conductors of the first coil conductors in a lamination direction of the insulating layers, is arranged along a surface of the insulating layers, and allows a high-frequency current to flow in a direction opposite a high-frequency current flowing in the first coil conductors.

Impedance matching transceivers may include a tuning circuit to match the transceiver module impedance to the housing conditions. In some examples, the impedance matching is controlled by tuning-circuits that may be integrated into a transceiver module by using a fan-out package (FO PKG). One example of a tuning circuit may include a switch to isolate the parallel capacitors, such that when the switch is on or closed the parallel capacitors are active.

The present invention is directed to communication systems and electrical circuits. According to an embodiment, the present invention provides a termination circuit that includes an inductor network. The inductor network is coupled to a termination resistor and a capacitor network, which includes a first capacitor and a second capacitor. The termination resistor, the first capacitor, and the second capacitor are adjustable, and they affect attenuation of the termination circuit. There are other embodiments as well.

A series noise absorption circuit, comprises: a differential signal transmission cable and a matching circuit. The differential signal transmission cable is electrically connected to two signal feedlines. The differential signal transmission has a first and second transmission line, the first transmission line and the second transmission line are configured to receive a differential pair of input signals from the two signal feedlines. The matching circuit is connected in series with the second transmission line. The matching circuit is configured to receive a reflective electrical signal from a noise reflection circuit, and match an input impedance corresponding the series noise absorption circuit with a common-mode impedance corresponding the two signal feedlines. A distance between the matching circuit and the noise reflection circuit is a minimal electrical length. The minimal electrical length is associated with a real part and an imaginary part of a matching impedance of the matching circuit.

A generator including a power combiner is provided. The power combiner includes a plurality of inputs, each input connectable to a respective power amplifier for receiving a respective power signal. A plurality of impedance matching circuit branches is connected to a respective one of the plurality of inputs. Each impedance matching circuit branch includes at least one high pass filter section and at least one low pass filter section through which the respective power signal passes. The impedance matching circuit branches are connected so as to combine the power signals from each power amplifier. An output is provided for outputting the combined power signal.

A method of manufacturing an RF switch includes adding a first mutual inductance portion to a first self-inductance portion of a first transmission line; and adding a second mutual inductance portion to a second self-inductance portion of a second transmission line, wherein values of the first and second mutual inductance portions and values of the first and second self-inductance portions equalize an impedance difference between the first transmission line and the second transmission line.

A radio-frequency switching apparatus that can be used to turn a signal path on or off or to attenuate a radio-frequency signal. The switching apparatus comprises at least one radio-frequency input, at least one radio-frequency output, at least one transmission line providing a signal path between the at least one radio-frequency input and the at least one radio-frequency output, and at least one transition metal oxide portion. The radio-frequency switching apparatus also comprises direct current blocking means electrically coupled between the at least one transition metal portion and the at least one radio-frequency input. The radio-frequency switching apparatus also comprises biasing means for providing a bias across the at least one transition metal oxide portion such that power transferred between the radio-frequency input and the radio-frequency output is controlled by controlling the bias level across the at least one transition metal oxide portion.

Disclosed is an impedance matcher for use in a communication system, operable to match a transmitter or receiver, respectively, to an associated antenna, comprising a stub matching circuit and a phase shifter, whereby, in use, energy flows from a source to the phase shifter, to the stub matching circuit and to a load.