A flexible multi-path RF adaptive tuning network switch architecture that counteracts impedance mismatch conditions arising from various combinations of coupled RF band filters, particularly in a Carrier Aggregation-based (CA) radio system. In one version, a digitally-controlled tunable matching network is coupled to a multi-path RF switch in order to provide adaptive impedance matching for various combinations of RF band filters. Optionally, some or all RF band filters include an associated digitally-controlled filter pre-match network to further improve impedance matching. In a second version, some or all RF band filters coupled to a multi-path RF switch include a digitally-controlled phase matching network to provide necessary per-band impedance matching. Optionally, a digitally-controlled tunable matching network may be included on the common port of the multi-path RF switch to provide additional impedance matching capability. In a third version, CA direct mapped adaptive tuning networks include filter tuning blocks for selected lower frequency bands.

Electromagnetic coupler systems including built-in frequency detection, and modules and devices including such. One example of an electromagnetic coupler system include an electromagnetic coupler having an input port, an output port, a coupled port, and an isolation port, the electromagnetic coupler including a main line extending between the input port and the output port, and a coupled line extending between the coupled port and the isolation port, the electromagnetic coupler being configured to produce a coupled signal at the coupled port responsive to receiving an input signal at the input port. An adjustable termination impedance is connected to the isolation port. A frequency detector is connected to the adjustable termination impedance and to the coupled port, and configured to detect a frequency of the coupled signal and provide an impedance control signal to tune the adjustable termination impedance based on the frequency of the coupled signal.

A flexible multi-path RF adaptive tuning network switch architecture that counteracts impedance mismatch conditions arising from various combinations of coupled RF band filters, particularly in a Carrier Aggregation-based (CA) radio system. In one version, a digitally-controlled tunable matching network is coupled to a multi-path RF switch in order to provide adaptive impedance matching for various combinations of RF band filters. Optionally, some or all RF band filters include an associated digitally-controlled filter pre-match network to further improve impedance matching. In a second version, some or all RF band filters coupled to a multi-path RF switch include a digitally-controlled phase matching network to provide necessary per-band impedance matching. Optionally, a digitally-controlled tunable matching network may be included on the common port of the multi-path RF switch to provide additional impedance matching capability. In a third version, CA direct mapped adaptive tuning networks include filter tuning blocks for selected lower frequency bands.

Disclosed are techniques for wireless communication. In an aspect, a band-pass filter of a radio frequency front end (RFFE) of a user equipment (UE) receives an analog radio frequency (RF) signal having a first bandwidth associated with a first sampling rate, the analog RF signal comprising a positioning reference signal (PRS). An analog-to-digital converter (ADC) of the UE samples the analog RF signal at a second sampling rate to generate a digital RF signal representing the analog RF signal, wherein the ADC operates at a second bandwidth lower than the first bandwidth, and wherein the second sampling rate is lower than the first sampling rate by an inverse of a folding factor for the first bandwidth. The digital RF signal is then output to a baseband processor of the UE.

A method of stabilizing a variable filter for an analog electromagnetic signal against circuit oscillation includes the steps of: providing a signal loop comprising a signal input, a signal output, and a plurality of variable circuit elements connected in the signal loop, the plurality of variable circuit elements comprising an adjustable resonator and an adjustable gain block, the signal loop having a variable frequency response that is characterized by a central frequency, a frequency passband, a response Q, and an operating point and a resonator response curve that are plottable in a Cartesian s-plane having an origin, a real axis, and an imaginary axis; and maintaining stability of the variable filter within an operating range by controlling the adjustable resonator and the adjustable gain block such that, in the Cartesian s-plane, the resonator response curve satisfies an orthogonality stability condition.

The present disclosure relates to a converter. The converter may include a first connector configured to transmit one or more signals, a second connector configured to receive the one or more signals, a first cable with a first impedance, a second cable with a second impedance, and an impedance module. The first connector may be connected to the impedance module via the first cable. The second connector may be connected to the impedance module via the second cable. The impedance module may be configured to convert the first impedance of the first cable to the second impedance of the second cable such that the one or more signals are transmitted from the first connector to the second connector via the first cable and the second cable.

A band pass filter includes a first filter circuit, a second filter circuit, a first intermediate circuit, a second intermediate circuit, and a ninth capacitor. The first intermediate circuit includes a seventh inductor connected between a fifth capacitor and a sixth capacitor. The second intermediate circuit includes an eighth inductor connected between a seventh capacitor and an eighth capacitor. The ninth capacitor is connected between the first intermediate circuit and the second intermediate circuit.

In tuning a radio frequency (RF) module including a non-volatile tunable RF filter, a desired frequency and an undesired frequency being provided by an amplifier of the RF module are detected. The non-volatile tunable RF filter is coupled to an output of the amplifier of the RF module. A factory setting of an adjustable capacitor in the non-volatile tunable RF filter is changed by factory-setting a state of a non-volatile RF switch, such that the non-volatile tunable RF filter substantially rejects the undesired frequency and substantially passes the desired frequency. The adjustable capacitor includes the non-volatile RF switch, and the factory setting of the adjustable capacitor corresponds to a factory-set state of the non-volatile RF switch. An end-user is prevented access to the non-volatile RF switch, so as prevent the end-user from modifying the factory-set state of the non-volatile RF switch.

A multilayer LC filter includes a multilayer body in which insulator layers, a ground electrode, capacitor electrodes, a planar electrode, and via electrodes includes open-side via electrodes connecting the capacitor electrodes and the planar electrode and short-circuit side via electrodes connecting the planar electrode and the ground electrode, an inductor is provided by a conductive path extending from the capacitor electrodes to the ground electrode through the open-side via electrodes, the planar electrode, and the short-circuit side via electrodes, a capacitor is provided by capacitance generated between the ground electrode and the capacitor electrodes, the inductor and the capacitor are connected in parallel to define LC resonators, and it is assumed that the short-circuit side via electrodes of all of the LC resonators in the multilayer body are made common.

Motion-detection systems are often used to detect presence of humans. Such motion-detection systems are often based on passive infrared (PIR) sensors. Unfortunately, such detection systems are unable to reliably distinguish between humans and other entities such as animals and moving heat sources. To address this issue, it is proposed to detect a presence of real time clock (RTC) devices in addition to detecting the heat sources to better determine whether a detected entity is a human.