Abstract: A measuring system includes a first measuring device and a second measuring device. The measuring system is configured to, between the first measuring device and the second measuring device, determine a first phase shift at a first frequency, determine a second phase shift at a second frequency, and determine a third phase shift at a third frequency. The first measuring device includes a phase difference calculator configured to calculate a first phase difference between the first phase shift and the second phase shift, and a second phase difference between the second phase shift and the third phase shift. The first measuring device also includes a range/velocity calculator configured to determine a first biased distance estimate from the first phase difference, a second biased distance estimate from the second phase difference, and an unbiased distance and/or velocity from the first biased distance estimate and the second biased distance estimate.

Abstract: Example embodiments relate to methods for adjusting an impedance of a tunable matching network, One embodiment includes a method for adjusting an impedance of a tunable matching network (TMN) connected between an antenna and a transceiver front-end. The TMN includes a receive path to provide signals from the antenna to a receiver during a receive (Rx) mode and a transmit path to provide signals from a transmitter to the antenna during a transmit (Tx) mode. The method includes tuning the TMN. The method also includes measuring values of an output DC-offset at the receiver while tuning the TMN. The output DC-offset is caused by a coupling between the transmitter and the receiver. Further, the method includes determining a maximum value of the output DC-offset from the measured output DC-offset values. Additionally, the method includes adjusting the impedance of the TMN by tuning the TMN to the output DC-offset maximum value.

Abstract: The present disclosure is directed to an impedance spectroscopy system for bio-impedance measurement. The impedance spectroscopy system includes a signal generator configured to generate a signal with a broadband frequency spectrum and to generate an analog injection current from the signal with the broadband frequency spectrum. The analog injection current has a high pass frequency characteristic. The impedance spectroscopy system also includes an amplifier configured to measure a voltage signal in response to the analog injection current and to simultaneously measure a biopotential signal. Further, the impedance spectroscopy system includes a processor configured to analyze the voltage signal to derive a bio-impedance spectrum as well to derive further information from the biopotential signal.

Abstract: A method of detecting a vital sign comprising at least one of a heart rate and a respiratory rate of a subject is provided. In one aspect, the method includes transmitting a radio frequency signal towards the subject; and receiving a reflected signal from the subject, wherein the transmitted signal is reflected by the subject and Doppler-shifted due to at least one of the heart rate and the respiratory rate to form the reflected signal. The method also includes mixing the reflected signal with a first reference signal; and providing a vital sign carrying signal based on the mixing to a first input of a phase or frequency comparator. The method further includes generating an adjustable second reference signal and providing the reference signal to a second input of the phase or frequency comparator; and generating an output signal, by the phase or frequency comparator.

Abstract: A method for localization and monitoring of living being targets in an environment comprise: transmitting (302) a sequence of radio frequency waveforms, the waveforms being a continuous-wave waveform modulated in frequency and/or phase; detecting (304) a sequence of reflected waveforms being reflected by a target and Doppler-shifted due to a movement of the target, forming (306) a sequence of waveform transforms, wherein the waveform transform comprises discretized information in a plurality of range bins, and wherein the information in a single range bin corresponds to reflections occurring at a specific sector in the environment; analyzing (308) information for a single specific sector in a sub-sequence of the sequence of waveform transforms, and determining (310) movement of a target in the specific sector based on the waveform transform information for that specific sector during a time period corresponding to the sub-sequence.

Abstract: A method for detecting a vital sign of a subject (102) comprises: receiving (302) a reflected radio frequency signal from the subject (102), the reflected signal being based on a transmitted signal, which is Doppler-shifted due to mechanical movements corresponding to the heart rate and/or the respiratory rate; dividing (304) a baseband signal into a sequence of sliding windows (200), each sliding window (200) representing a time interval; estimating (306) a vital sign parameter in at least one sliding window (200); determining (308) whether a vital sign parameter may be reliably estimated in at least one sliding window (200); on condition that the vital sign parameter may not be reliably estimated in a sliding window (200), determining (310) a vital sign parameter of the sliding window (200) based on vital sign parameters estimated in a plurality of windows representing time intervals close to the time interval of the window (200).

Abstract: A method for stimulating a human leg, a stimulation system, and a garment including the stimulation system are disclosed. The method comprises: measuring, by a measuring unit, an electrical characteristic indicative of a physiological condition in a portion of the leg via a subset of skin electrodes comprised in a plurality of skin electrodes integrated in a leg part of a garment arranged to be worn about at least a part of the human leg; determining, by evaluating the measured electrical characteristic, if the portion of the leg is to be stimulated; and if it is determined that the portion is to be stimulated, applying a stimulation via a subset of stimulation units, comprised in a plurality of stimulation units being arranged in the leg part of the garment, such that the portion of the leg is stimulated. A stimulation system and a garment comprising such as stimulation system are also disclosed.

Abstract: An oscillator is configured to generate a signal with a frequency sweep, the oscillator having circuitry comprising a set of capacitors, each capacitor of the set of capacitors being switchably connectable in parallel in the circuitry so that the frequency of the signal has an intrinsic dependence on the number of the capacitors connected, a shift register controllable by a clock line and comprising a number of bits, each bit of the number of bits controlling connection of a respective capacitor of the set of capacitors so that the capacitors are connectable or disconnectable in a pre-determined order by shifting, respectively, activation or de-activation bits into the shift register, wherein the shifting is paced by the clock line; and a clock signal generator configured to output a clock signal with a time modulation on the clock line.

Abstract: A method for determining a distance between a first radio signal transceiver and a second radio signal transceiver using narrowband ranging comprises calculating a preliminary estimate of a value proportional to a one-way frequency domain channel response, based on measurements of signal phase and signal strength; calculating, for pairs of adjacent frequencies, an estimate of a value proportional to a time synchronization offset between a clock used by the first radio signal transceiver and a clock used by the second radio signal transceiver, and determining a final estimate of a value proportional to the one-way frequency domain channel response based on the preliminary estimate and adjacent estimates for the value proportional to the time synchronization offset, where the final estimate is used for the final distance determination.

Abstract: An LC oscillator powering arrangement comprises an LC oscillator configured to provide an oscillating signal output; a current source configured to supply the LC oscillator with a supply current, the current source during operation being controlled by a control voltage and supplied with a supply voltage subject to supply voltage ripple; and a replication block configured to generate an amplified replica of the supply voltage ripple directly from the supply voltage and to overlay the replica on the control voltage.

Abstract: A battery operated device and method of removing a battery therefrom are described. The battery operated device includes a battery compartment, a battery in the battery compartment, and an electric component powered by the battery. The battery compartment is mounted on a deformable base and includes a top surface which is adapted to be ruptured by deforming the deformable base, thereby enabling removal of the battery from the battery compartment. The method of removing a battery from a battery compartment of a battery operated device includes rupturing a top surface of the battery compartment by deforming a deformable base of the battery compartment, and removing the battery from the battery compartment.

Abstract: A switched-capacitor power amplifier comprising a plurality of cells and methods for its operation are described. Switched signal lines switch supply to respective capacitors. Switches connect respective signal lines to a first supply and switches connect respective signal lines to a second supply. Pairs of switches on each signal line are switched so that one is switched off whilst the other is switched on. In a “full amplitude” mode, operation of the switches provides an output having a peak determined by the first supply. A switch signal line is provided between nodes in respective signal lines, a switch being provided in the switch signal line. In a “half amplitude” mode, switch is switched at the radio frequency in the other direction to that of switches connecting the signal lines to respective ones of the first and second supplies with the other switches being kept open.

Abstract: A signal generator comprises (i) a first set of capacitors at least partially switchably connectable for adjusting a frequency of an oscillator as part of a phase-locked loop and (ii) a second set of capacitors comprised in one or more oscillator control subsystems. A method of controlling the signal generator comprises: (i) acquiring a frequency lock in the phase-locked loop, (ii) calculating, in conjunction with the acquiring of the frequency lock, a systematic capacitance error of the first set of capacitors due to process, voltage, and temperature variations based on the frequency of the oscillator and a switching state of the first set of capacitors, and (iii) calibrating the one or more oscillator control subsystems using the systematic capacitance error, thereby compensating for process, voltage, and temperature variations common between the first set of capacitors and the second set of capacitors.

Abstract: An example oscillator device comprises (i) an oscillation circuit arranged for generating and outputting an oscillation signal and comprising an active circuit to ensure oscillation is maintained, (ii) a voltage-to-current conversion replica circuit of the active circuit arranged for receiving the oscillation signal and for outputting a current proportional to the oscillation signal, (iii) biasing means arranged to generate a constant bias current to activate the oscillation circuit, and (iv) subtraction means for subtracting the current proportional to the oscillation signal from the bias current, thereby obtaining a resulting current which can be used for adapting the oscillation signal's amplitude.

Abstract: A solid-state device for photo detection, in general, of terahertz radiation is disclosed. One aspect is a detector device comprising a body having a photoconductive material, a first antenna element connected to a first portion of the body, and a second antenna element connected to a second portion of the body. The first antenna element and the second antenna element are arranged to induce an electric field in the body in response to an incident signal. Further, the device has a waveguide arranged to couple light into the photoconductive material via a coupling interface between the waveguide and the body, where the coupling interface faces away from the first portion and the second portion of the body and is closer to the first portion than to the second portion.

Abstract: A differential Colpitts oscillator circuit is described which has center-tapped inductors which are cross-coupled with gates of second transistors of first and second transistor pairs which can reduce the minimum power supply voltage and the bias voltage for the circuit. In addition, a capacitive ladder can be implemented which also has the potential benefit of increased tuning range.

Abstract: A low dropout, LDO, voltage regulator comprising: an LDO input configured to receive an input voltage signal; an LDO output configured to output an output voltage signal; an error amplifying circuit, which is configured to receive a reference signal and a feedback signal associated with the output voltage signal, the error amplifying circuit being further configured to output an error signal; an output stage, which is configured to receive the error signal and output a control signal; and an output device, which is connected to the LDO input and configured to provide the output voltage signal and which is controlled by the control signal for regulating the output voltage signal; wherein the output stage is connected to the input voltage for receiving an adaptive bias current.

Abstract: According to an aspect of the present inventive concept there is provided a method for eye tracking, comprising: capturing a sequence of digital images of an eye of a user; outputting data including said sequence of images to an image processing unit; processing said data by the image processing unit to determine a sequence of positions of the eye, each position being indicative of a gaze direction, acquiring biosignal data representing an activity of the eye; and in response to detecting closing of the eye based on the acquired biosignal data, pausing at least one of said capturing, said outputting and said processing. A system for implementing the method is also disclosed.

Abstract: According to one aspect of the inventive concept there is provided a system for monitoring incontinence comprising: a urine sensitive circuit arranged to present a changed electrical characteristic when exposed to urine; a measurement circuit arranged to perform a measurement on a urine bladder of a wearer to determine at least one parameter which varies with a fill level of the urine bladder; a sensor arranged to determine an orientation and/or a movement of the sensor; and a processing circuit arranged to: determine whether the urine sensitive circuit has been exposed to urine; estimate an amount of urine released on to the urine sensitive circuit; and in response to determining that the urine sensitive circuit has been exposed to urine, record data representing said at least one parameter determined by the measurement circuit, an estimated movement and/or posture of the wearer based on an orientation and/or a movement determined by the sensor, and an estimate of the amount of urine released on to the urine

Abstract: A digital power amplification circuit includes a decoding block configured to receive a first stream of digital codes and to derive from the first stream a second stream of digital codes, the decoding block including a decoder configured to decode the digital codes of the first stream and the second stream at a first clock rate, a main digital power amplifier configured to receive the decoded digital codes of the first stream, an upsampler configured to upsample the decoded digital codes of the second stream to a second clock rate that is greater than the first clock rate, an auxiliary digital power amplifier configured to receive the decoded digital codes of the second stream upsampled to the second clock rate, and a summer configured to sum (i) a main output signal of the main digital power amplifier and (ii) an auxiliary output signal of the auxiliary digital power amplifier.