Abstract: A power receiver (105) communicates to a power transmitter (101) using load modulation data symbols modulated by a chip sequence with a chip sequence being divided into load time intervals with different modulation loads. The power transmitter (101) comprises a receiver (207) which includes a load measurer (209) determining measured load values of the power transfer signal for load time intervals. A chip determiner circuit (211) determines a received chip sequence from the measured load values where the received chip sequence comprises a sequence of chip values. Each chip value is determined in response to a difference between measured load values for at least two modulation load time intervals of the chip. A store (215) stores a set of chip sequences with each chip sequence linked to a data symbol. A detector (213) detects a received data symbol value in response to a correlation between the received chip sequence and chip sequences of the set of chip sequences.

Abstract: There is provided a wireless power transfer system comprising a power transmitter for providing power to a power receiver via an inductive power signal which comprises a power transmitter which in turn comprises a transmitter resonant circuit comprising a power transmitting inductor having a transmission resonance at a first frequency and arranged for generating the power transfer signal, the power transmitting inductor being arranged to be magnetically couplable to a power receiver inductor in the power receiver, a power transmitter driver, operably coupled to the power transmitter resonant circuit and arranged to generate a drive signal for the power transmitting inductor, a transmitter communication resonant circuit, different from the transmitter resonant circuit and directly or capacitively coupled to the power transmitting inductor, being arranged to establish a transmitter communication resonance at a second frequency, different from the first frequency, for communications, wherein the power transmitti

Abstract: A power transmitter (101) provides power to a power receiver (105) via an inductive power transfer signal which is also used by the power receiver (105) for communication by load modulation. The power receiver (105) comprises a transmitter (509) arranged to transmit symbols in accordance with a first or second communication mode where the first mode modulates data symbols by a chip sequence from a set of sequences and the second communication mode does not. The power receiver (105) may transmit data symbols requesting a power transfer signal variation using a chip sequence from the set. A detector (515) may detect if the variation occurs, and if so a selector (513) selects the first communication mode and otherwise it selects the second communication mode. The approach may allow selection of an appropriate communication mode without requiring data to be transmitted from the power transmitter. The approach may provide improved backwards compatibility.

Abstract: A power transfer system comprises a power transmitter (101) wirelessly providing power to a power receiver (105) via an inductive power transfer signal. Communication from power receiver (105) to the power transmitter (101) is by load modulation using the power transfer signal. The communication uses load modulation where each symbol is represented by a chip sequence being a sequence of modulation load values. The power transmitter (101) comprises a first communicator (207) which correlates a chip sequence received from the power receiver with a set of reference chip sequences being linked to data symbol values and determines the data symbol as the data symbol linked to a reference chip sequence for which the highest correlation with the first chip sequence is determined.

Abstract: A power transmitter (101) transfers power to a power receiver (105) and comprises a power input (209) receiving supply power. A power detector (211) detects a restoring of the supply power following an outage, and a presence detector (213) detects the presence of the power receiver when supply power is being restored. A first communicator (207) can communicate with a second communicator (509) of the power receiver (105) using a short range communication channel. A message circuit (215) transmits a power restore message to the second communicator (509) when supply power is being restored. A user action detector (217) detects a power receiver user action and a controller (205) arranged to initiate a power transfer to the power receiver after power restoration in response to the detection of the user action and to inhibit initiation of the power transfer after power restoration if the user action is not detected. The power receiver (105) can generate a user alert when receiving the power restore message.

Abstract: A power transfer apparatus being a power transmitter (101) or power receiver (103) of a power transfer via a power transfer signal comprises a power coil (103, 107) for transferring power with a complementary power transfer coil (107, 103) being the other apparatus of the power transfer operation. A first communicator (205, 305) communicates data with the complementary power transfer apparatus using modulation of the power transfer signal. A second communicator (207, 307) communicates power transfer control data via a second communication channel that is independent of the power transfer signal and has a communication data rate at least ten times higher.

Abstract: A power transfer apparatus being a power transmitter (101) or power receiver (103) of a power transfer via a power transfer signal comprises a power coil (103, 107) for transferring power with a complementary power transfer coil (107, 103) being the other apparatus of the power transfer operation. A first communicator (205, 305) communicates data with the complementary power transfer apparatus using modulation of the power transfer signal. A second communicator (207, 307) communicates power transfer control data via a second communication channel that is independent of the power transfer signal and has a communication data rate at least ten times higher.

Abstract: There is provided a wireless power transfer system comprising a power transmitter for providing power to a power receiver via an inductive power signal which comprises a power transmitter which in turn comprises a transmitter resonant circuit comprising a power transmitting inductor having a transmission resonance at a first frequency and arranged for generating the power transfer signal, the power transmitting inductor being arranged to be magnetically couplable to a power receiver inductor in the power receiver, a power transmitter driver, operably coupled to the power transmitter resonant circuit and arranged to generate a drive signal for the power transmitting inductor, a transmitter communication resonant circuit, different from the transmitter resonant circuit and directly or capacitively coupled to the power transmitting inductor, being arranged to establish a transmitter communication resonance at a second frequency, different from the first frequency, for communications, wherein the power transmitti

Abstract: A power transfer apparatus being a power transmitter (101) or power receiver (103) of a power transfer via a power transfer signal comprises a power coil (103, 107) for transferring power with a complementary power transfer coil (107, 103) being the other apparatus of the power transfer operation. A first communicator (205, 305) communicates data with the complementary power transfer apparatus using modulation of the power transfer signal. A second communicator (207, 307) communicates power transfer control data via a second communication channel that is independent of the power transfer signal and has a communication data rate at least ten times higher.

Abstract: A sleep monitoring system has a movement sensing arrangement and a controller for identifying from the movement sensing arrangement output signals sleep-disordered breathing events. Seismocardiography signals are recorded and analyzed to determine repetitive patterns, from which an inter-beat interval time series is derived without identifying specific elements of the repetitive patterns. The sleep-disordered breath events are derived from the inter-beat interval time series. In this way, SCG signals can be used for sleep monitoring in a robust and reliable way.