An apparatus for tuning a plurality of antennas is provided. The apparatus includes a plurality of antenna ports connected to the plurality of antennas; a plurality of user ports; first adjustable impedance elements, each being connected to one of the antenna ports and ground; second adjustable impedance elements, each being connected to one of the user ports and another one of the user ports; and a plurality of connecting elements, each being connected to one of the antenna ports and one of the user ports, wherein the first and second adjustable impedance elements are configured to be adjustable so to tune the plurality of antennas.

An apparatus for a network matching switch is provided. The apparatus includes a primary winding, a first secondary winding, a second secondary winding and a plurality of matching network paths. The primary winding is configured to generate a magnetic field based on an analog input signal. The first secondary winding is configured is inductively coupled to the primary winding. The second secondary winding is inductively coupled to the primary winding. The plurality of matching network paths are coupled to the first secondary winding and the second secondary winding. An active path is selected from the plurality of matching network paths and provides power to an active load.

An electromagnetic coupler apparatus includes a plurality of couplers, each having a coupled port and an isolation port. The coupler apparatus includes an output port configured to provide a coupled signal from one or more of the plurality of couplers, and a number of selection control inputs. Each of the selection control inputs is configured to control one or more switches to select an individual one of the plurality of couplers to provide at least a portion of the coupled signal at the output port.

A branching device (10) includes a switch (SW1), a fixed filter circuit (11), and a tunable filter (TF1). The switch (SW1) includes a common terminal (Ps11) and individual terminals (Ps12, Ps13). The fixed filter circuit (11) is connected to the individual terminal (Ps12) and has a fixed pass band. The tunable filter (TF1) is connected to the individual terminal (Ps13) and has a tunable pass band. The fixed filter circuit (11) includes filters (FIL1, FIL2) having different pass bands. The pass bands of the filters (FIL1, FIL2) correspond to frequency bands to be used in carrier aggregation.

An integrated circuit (IC) device includes a die having an integrated passive device (IPD) layer. The integrated circuit device also includes a substrate supporting the die, a molding compound surrounding the die. The integrated circuit device further includes a backside conductive layer on a surface of the die that is distal from the IPD layer. The integrated circuit device also includes vias coupling the backside conductive layer to a ground plane through the molding compound.

Certain aspects of the present disclosure provide a directional coupler. In certain aspects, the directional coupler generally includes a first inductor and a second inductor wirelessly coupled to the first inductor. In certain aspects, the directional coupler generally includes an input port at a first terminal of the first inductor and a transmitted port at a second terminal of the first inductor. In certain aspects, the directional coupler generally includes a coupled port at a first terminal of the second inductor and an isolated port at a second terminal of the second inductor. In certain aspects, the directional coupler generally includes a first complex impedance component directly coupled to the isolated port and a second complex impedance component directly coupled to the coupled port.

Methods and apparatus, including computer program products, are provided filters. In some example embodiments, there is provided a radio frequency filter including at least one resonant circuit selectable to vary at least the selectivity of the radio frequency filter, wherein the selectivity is varied based on at least one of a first amount of transmit power being used at a user equipment and a second amount of received signal power. Related apparatus, systems, methods, and articles are also described.

An integrated circuit (IC) device includes a die having an integrated passive device (IPD) layer. The integrated circuit device also includes a substrate supporting the die, a molding compound surrounding the die. The integrated circuit device further includes a backside conductive layer on a surface of the die that is distal from the IPD layer. The integrated circuit device also includes vias coupling the backside conductive layer to a ground plane through the molding compound.

An apparatus for tuning a plurality of antennas is provided. The apparatus includes a plurality of antenna ports connected to the plurality of antennas; a plurality of user ports; first adjustable impedance elements, each being connected to one of the antenna ports and ground; second adjustable impedance elements, each being connected to one of the user ports and another one of the user ports; and a plurality of connecting elements, each being connected to one of the antenna ports and one of the user ports, wherein the first and second adjustable impedance elements are configured to be adjustable so to tune the plurality of antennas.

A wide band directional coupler comprises a first transmission line, a second transmission line and at least one inductor, wherein the first transmission line and the second transmission line are adjacent each other, and the inductor connects to the second transmission. As a RF signal passes through the first transmission line, the second transmission line will couple with the RF signal in the first transmission line to generate a coupling signal. The inductor is connected to the second transmission line to improve the coupling factor and/or the insertion loss of the wide band directional coupler at high frequency band.