An apparatus includes a substrate and a three-dimensional (3D) wirewound inductor integrated within the substrate. The apparatus further includes a capacitor coupled to the 3D wirewound inductor.

The invention relates to a filter circuit which, on the hardware level, prevents charge transfers caused by one or more currents in a frequency divider (200) from generating an interference signal that can cause a signal distortion at the output of a current-to-voltage converter (300) belonging to a filter circuit. This signal distortion would otherwise have to be removed by means of laborious post-processing of the signal. In this process, the voltage curve at the input of the frequency divider (200) or the current at the second output of the frequency divider (200) are employed so that, by means of a compensation circuit arrangement, it is possible to model a compensation signal that essentially compensates for an interference signal caused by the charge transfers. The invention also relates to an associated method.

In a filter arrangement comprising a frequency filter (F) that has a bad or non-ideal ground connection (GC1, 2, 3, 4, 5, 6, 7), the defects arising from bad ground are compensated by a capacitance (CC) coupled in parallel to the frequency filter. The value of the capacitance is chosen between 1 and 50 fF. The filter arrangement may be a receiving filter (RF) in a duplexer (DU).

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.

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 electronic device includes multiple antennas to transmit one or more signals, and a transmitter electrically coupled to the antennas. The transmitter has splitter circuitry that receives an input signal and generates the signals. The splitter circuitry includes a pair of inductive elements that are inductively coupled together. The splitter circuitry includes capacitive elements to absorb parasitic input and output capacitance. In additional or alternative embodiments, the splitter circuitry may be in the form of combiner circuitry and disposed in a receiver of the electronic device.

An electronic device includes multiple antennas to transmit one or more signals, and a transmitter electrically coupled to the antennas. The transmitter has splitter circuitry that receives an input signal and generates the signals. The splitter circuitry includes a pair of inductive elements that are inductively coupled together. The splitter circuitry includes capacitive elements to absorb parasitic input and output capacitance. In additional or alternative embodiments, the splitter circuitry may be in the form of combiner circuitry and disposed in a receiver of the electronic device.