In certain aspects, an apparatus includes a power detector coupled between a power amplifier and an antenna, and a voltage detector coupled between the power amplifier and the antenna. The apparatus also includes a phase shifter coupled to the power detector, and a load measurement circuit coupled to the power detector, the voltage detector, and the phase shifter.

In certain aspects, an apparatus includes a power detector coupled between a power amplifier and an antenna, and a voltage detector coupled between the power amplifier and the antenna. The apparatus also includes a phase shifter coupled to the power detector, and a load measurement circuit coupled to the power detector, the voltage detector, and the phase shifter.

A measuring device for measuring current effective power in a circuit of a transmission system, including an evaluation device and a calibration device, the evaluation device having a connection for measuring current, voltage, and phase shift between the current and the voltage in the circuit, wherein the evaluation device and the calibration device are connected to one another, the evaluation device configured to measure power by evaluating measured current and measured voltage, the calibration device configured to correct the measured current and/or the measured voltage via a cos ( ) value of a measured phase shift between the measured current and the measured voltage and/or via a holding time, the evaluation device configured to calculate a power value with a corrected value of the measured current and/or a corrected value of the measured voltage, and the calibration device configured to make available the calculated power as the current effective power.

The invention relates to a method for determining a state of at least one cell of a battery, wherein the battery has a plurality of cells, which are connected in series with each other, the method comprising at least the following steps: a) applying an alternating current to the plurality of cells; b) measuring the alternating voltage produced thereby at at least a first cell and a second cell; c) analyzing a phase position of the measured alternating voltage of each cell; wherein a difference at least between a first phase position of a first alternating voltage measured at the first cell and a second phase position of a second alternating voltage measured at the second cell forms a conclusion about a difference between the states of at least the first cell and the second cell.

A system for passive microwave remote sensing using at least one microwave radiometer includes a fixed body portion, the fixed body portion being configured to attach to a mobile platform, and a mobile body portion, the mobile body portion being configured for rotatably coupling with the fixed body portion for rotation about a rotation axis. The mobile body portion is configured for supporting the at least one microwave radiometer therein such that the at least one microwave radiometer rotates about the rotation axis when the mobile body portion is rotated about the rotation axis such that a polarization axis of the at least one radiometer is aligned with an earth axis. The fixed body portion includes a motor mechanism for effecting rotation of the mobile body portion such that the at least one microwave radiometer provides a vertical scanning below and above the mobile platform.

A method for determining and/or adjusting phases of at least two electrical signals is disclosed. The method includes the following steps: a first frequency and/or a first power level for a first signal is set and a second frequency and/or a second power level for a second signal is set. The first signal and the second signal are superposed, thereby obtaining a superposed signal. A power parameter of the superposed signal is determined via a power measurement unit for several different phase offsets of the first signal and/or of the second signal. A relative phase between the first signal and the second signal is determined and/or set based on the determined power parameters. Moreover, a signal generator system is disclosed.

The invention provides a method and system for precisely measuring AC power and detecting load impedance using a precise analog front-end, zero-crossing detectors, and a phase detection system capable of extracting precise phase information from the sensed voltage and current measurements. More particularly, the invention provides an apparatus, comprising a transmit circuit configured to generate a wireless field via an antenna for transferring charging power to a receiver device, for determining a phase difference between a first signal and a second signal. The apparatus further comprises a phase detection circuit to output a phase signal indicating a duration of a phase offset between a time-varying voltage and a time-varying current of the transmit circuit. The apparatus further comprises a capacitor configured to receive a variable current from a current source for the duration of the phase offset between the time-varying voltage and a time-varying current.

The invention provides a method and system for precisely measuring AC power and detecting load impedance using a precise analog front-end, zero-crossing detectors, and a phase detection system capable of extracting precise phase information from the sensed voltage and current measurements. More particularly, the invention provides an apparatus, comprising a transmit circuit configured to generate a wireless field via an antenna for transferring charging power to a receiver device, for determining a phase difference between a first signal and a second signal. The apparatus further comprises a phase detection circuit to output a phase signal indicating a duration of a phase offset between a time-varying voltage and a time-varying current of the transmit circuit. The apparatus further comprises a capacitor configured to receive a variable current from a current source for the duration of the phase offset between the time-varying voltage and a time-varying current.

A phase adjustment device includes: a detection signal generator configured to generate a pair of first and second detection signals for detecting a phase difference between two signals whose phases have been adjusted by two phase adjusters, respectively, a maximum sensitivity phase difference of one of the first and second detection signals being not overlap with that of the other, and detection sensitivity of the phase difference becoming maximum at the maximum sensitivity phase difference; a detection signal selector configured to select one of the first and second detection signals whose predetermined range around the maximum sensitivity phase difference covers a preset phase difference; and a phase controller configured to control an amount of phase-adjusting by at least one of the two phase adjusters based on a difference between the phase difference detected within the predetermined range using the selected detection signal and the preset phase difference.

A phase adjustment device includes: a detection signal generator configured to generate a pair of first and second detection signals for detecting a phase difference between two signals whose phases have been adjusted by two phase adjusters, respectively, a maximum sensitivity phase difference of one of the first and second detection signals being not overlap with that of the other, and detection sensitivity of the phase difference becoming maximum at the maximum sensitivity phase difference; a detection signal selector configured to select one of the first and second detection signals whose predetermined range around the maximum sensitivity phase difference covers a preset phase difference; and a phase controller configured to control an amount of phase-adjusting by at least one of the two phase adjusters based on a difference between the phase difference detected within the predetermined range using the selected detection signal and the preset phase difference.