Abstract: A wireless power transfer system comprises at least one power receiver (105) for receiving a power transfer from the power transmitter (101) via a wireless inductive power transfer signal. Configurers (207, 306) of the power transmitter and receiver may perform a configuration process to determine a set of power transfer parameter values which are used in a first power transfer. The power transfer parameter values and a first identity for the first power receiver (105) are stored. After a detection of an absence of the power receiver by a first controller (211), a detector (213) may detect a presence of a candidate power receiver. If the candidate power receiver is detected within a given duration and has an identity matching the first identity, an initialization processor (215) initializes a second power transfer using the set of stored parameter values. Otherwise it discards the set of stored parameter values.

Abstract: A wireless power transfer system comprises at least one power receiver (105) for receiving a power transfer from the power transmitter (101) via a wireless inductive power transfer signal. Configurers (207, 306) of the power transmitter and receiver may perform a configuration process to determine a set of power transfer parameter values which are used in a first power transfer. The power transfer parameter values and a first identity for the first power receiver (105) are stored. After a detection of an absence of the power receiver by a first controller (211), a detector (213) may detect a presence of a candidate power receiver. If the candidate power receiver is detected within a given duration and has an identity matching the first identity, an initialization processor (215) initializes a second power transfer using the set of stored parameter values. Otherwise it discards the set of stored parameter values.

Abstract: A wireless power receiver, method, and corresponding processing circuitry for the same are disclosed. The wireless power receiver includes a receiver coil configured to receive a wireless power transfer signal transmitted by a wireless power transmitter and a load coupled to the receiver coil. The wireless power receiver further includes communication circuitry configured to communicate a synchronization message to the wireless power transmitter which indicates time durations for repeating time intervals of foreign object detection and wireless power transfer. The foreign objection detection time periods correspond to periods of reduced power transfer to improve detection of foreign objects.

Abstract: In a wireless optical network with multiple coordinators or other access points, the coverage area of coordinators may overlap. Interference in the communication between coordinators and devices may occur in these overlapping coverage areas. Various embodiments propose an automatic allocation of reserved time slots to coordinators. These time slots support the coordinators to advertise their presence without interference and enable a device to detect the presence of a neighbour coordinator in a single MAC cycle. Cooperation of coordinators can be supervised by a global controller to determine non-interfering time schedules whereby the coordinators rely on interference reports from the devices in the overlapping coverage areas. Fast detection allows fast re-scheduling of time slots in the wireless optical network in order to prevent interference when a device that enters the overlapping coverage area of two coordinators.

Abstract: An inductive power transfer system is arranged to transfer power from a power transmitter to a power receiver via a wireless power signal. The system supports communication from the power transmitter to the power receiver based on load modulation of the power signal. The power receiver transmitting a first message to the power transmitter which comprises a standby power signal requirement for the power signal during a standby phase. The power transmitter receives the message, and when the system enters the standby phase, the power transmitter provides the power signal in accordance with the standby power signal requirement during. A power receiver configurable standby phase is provided which may for example allow devices to maintain battery charge or to provide fast initialization of the power transfer phase.

Abstract: Given the potential high data rate and privacy of Optical Wireless Communication, Li-Fi turns out to be an attractive technology for enabling high-speed wireless data transfer between remote devices. This invention is directed to various methods, systems and apparatus for enabling high-speed file transfer via a high-speed Li-Fi link (200) between a user-held apparatus (300) and a remote device (400). Upon a trigger command received by the user-held apparatus (300), a trigger signal is sent to the remote device (400) via another communication link (500) having a wide beam width. The remote device (400) provides a human perceivable indication of a dedicated reception area after receiving the trigger signal to assist a user to adjust the user-held apparatus (300) for an alignment needed to enable the high-speed Li-Fi link (200). The high-speed file transfer starts after the alignment status is determined allow for file transfer, or a start-to-send command is received by the user-held apparatus (300).

Abstract: In a wireless optical network with multiple coordinators or other access points, the coverage area of coordinators may overlap. Interference in the communication between coordinators and devices may occur in these overlapping coverage areas. Various embodiments propose an automatic allocation of reserved time slots to coordinators. These time slots support the coordinators to advertise their presence without interference and enable device to detect the presence of a neighbour coordinator in a single MAC cycle. Fast detection allows fast re-scheduling of time slots in the wireless optical network in order to prevent interference when a device that enters the overlapping coverage area of two coordinators.

Abstract: A wireless power transmitter (101) an output circuit (203, 103) comprises a transmitter coil (103) for which generates the power transfer signal a drive signal generated by a driver circuit (201) is applied. A power loop controller (209) implements a power control loop for controlling the drive signal to adjust a power level of the power transfer signal in response to power control error messages received from the power receiver (105). A mode store (213) stores a plurality of power level modes for the power receiver where each power level mode is associated with a reference power level for the power transfer signal. A mode circuit (211) adapts the drive signal to set the power level of the power transfer signal to a first reference value in response to receiving a mode request message where the first reference value corresponds to a reference power level for a first power level mode indicated in the mode request message.

Abstract: A power transmitter (101) for a wireless power transfer system comprises a transmitter coil (103) and a driver (201) generates a drive signal) for the transmitter coil (103) employing a repeating time frame with a power transfer time interval and a reduced power time interval during which a power level of the power transfer signal is reduced. A driver (201) generates a drive signal for the transmitter coil (103) to generate the power transfer signal. A communicator (205) receives messages from the power receiver (105) and an adapter (213) adapts a timing property of the reduced power time interval in response to at least a first message received from the power receiver (105). A synchronizer (206) for synchronizing a foreign object detection and the generation of a test signal to occur during the reduced power time interval. The operation may typically be a foreign object detection or communication, and the timing property may e.g. be a duration of the reduced power time interval.

Abstract: For time-division based wireless optical networks, it is important to keep neighboring coordinators synchronized to a common time base, in order to avoid interference to a network device located in the overlapping area of such neighboring coordinators. However, given that the common time base is located remotely, there is still timing synchronization uncertainty remaining at a coordinator side. A novel auxiliary scheduler subsystem, and the related methods and systems, are disclosed in this invention. By reserving time margins in the allocated time slots by the auxiliary scheduler subsystem, interference due to timing synchronization uncertainty is reduced.

Abstract: A wireless power transfer system includes a power transmitter (201) arranged to provide a power transfer to a power receiver (205) via a power transfer signal. The power receiver (205) comprises a first mode controller (709) for transmitting a standby mode exit request to the power transmitter (201) by changing a loading of a communication inductor (209) of the power transmitter (201). The power transmitter (201) comprises a mode controller (405) which controls the power transmitter (201) to operate in a standby mode wherein a presence of the power receiver (205) is detected but no power transfer signal is generated. It furthermore comprises a detector (403) for detecting an impedance change of the communication inductor (209). The mode controller (405) is arranged to initiate a transition from the standby mode to a power transfer mode in response to the detector (403) detecting the impedance change.

Abstract: A power transmitter (101) for a wireless power transfer system comprises a transmitter coil (103) and a driver (201) generates a drive signal for the transmitter coil (103) employing a repeating time frame with a power transfer time interval and a foreign object detection time interval. A test generator (211) generates a test drive signal for a test coil (209) during the foreign object detection time interval. A foreign object detector (207) performs a foreign object detection test based on a measured parameter for the test drive signal. Prior to entering a power transfer phase, an adapter (213) controls the power transmitter (101) to operate in a foreign object detection initialization mode in which a preferred value of a signal parameter for the test drive signal is determined in response to at least a first message received from the power receiver (105). During the foreign object detection time interval the signal parameter of is set to the preferred value.

Abstract: A wireless power transfer system includes a power receiver (105) receiving a power transfer from a power transmitter (101) via a wireless inductive power transfer signal. The power transmitter (101) comprises a transmit power coil (103) generating the power transfer signal. A test signal coil (209) coupled to a test signal generator (211) generates a magnetic test signal. A plurality of spatially distributed detection coils (213) is coupled to measurement unit (215) generating a set of measurement values reflecting signals induced in the detection coils (213) by the magnetic test signal. A processor (217) determines a measurement spatial distribution of the measurement value where the spatial distribution reflects positions of the detection coils (213). A foreign object detector (219) detects a presence of a foreign object in response to a comparison of the measurement spatial distribution to a reference spatial distribution.

Abstract: According to one aspect disclosed herein, there is provided a system (500) comprising at least two light cells (504, 508) connected to form a light communication network. The system comprises at least two light cells each formed by a respective first beam of light comprising a respective data signal and a second beam of light comprising a pilot signal. Each data signal has an amplitude profile with a portion above a pre-determined threshold level (316), and said portion of the respective data signals of the at least two light cells partially overlap to form an overlapping region (306) with an amplitude profile (720, 730) above the predetermined threshold level. Each pilot signal in turn has an amplitude profile (740, 750) which comprises an ascending edge and a descending edge and a footprint which is aligned with a footprint of the respective data signal for use in performing a pre-handover and/or handover.

Abstract: The invention proposes a method of encoding data packet by encoding type information and size information of said data packet into the same field. The invention also proposes a method of processing data packets received. The data packet comprises a header part and a message part. The header part comprises at least one bit for indicating the type of said data packet, said method comprising a step 101 of obtaining the size information of said data packet based on said at least one bit.

Abstract: A power receiver receives a wireless power transfer from a power transfer signal generated by a wireless power transmitter during a power transfer phase. The power transfer signal employing a repeating time frame during the power transfer phase where the frame comprises at least a power transfer time interval and a foreign object detection time interval. The power receiver comprises a synchronizer (311) which synchronizes a local time reference to the repeating time frame and a load controller (309) which disconnects a load (303) during at least part of the foreign object time detection time intervals during at least part of the power transfer phase. The timing of the disconnecting is dependent on the local time reference. A mode controller (313) switches between a first operational mode and a second operational mode for the power transfer time intervals in response to a reliability measure for the synchronization.

Abstract: A system comprising: a plurality of first devices, each configured to transmit a low-frequency, LF, light signal comprising an identifier of the respective first device, and to transmit and/or receive a high-frequency, HF, light signal comprising data content; and a second device configured to receive a LF light signal from each of the first devices, and to transmit and/or receive a HF light signal from at least one first device, wherein the second device has an adaptable receiving and/or transmitting direction for respectively receiving and/or transmitting the HF light signal, and wherein the second device comprises a controller configured to: based on the identifiers encoded in the LF light signals, determine a position of the second device relative to the first devices and select a first device; and based on the determination, adapt the receiving and/or transmitting direction toward the selected first device.

Abstract: The invention proposes a method of encoding data packet by encoding type information and size information of said data packet into the same field. The invention also proposes a method of processing data packets received. The data packet comprises a header part and a message part. The header part comprises at least one bit for indicating the type of said data packet, said method comprising a step 101 of obtaining the size information of said data packet based on said at least one bit.

Abstract: A power receiver receives a wireless power transfer from a power transfer signal generated by a wireless power transmitter during a power transfer phase. The power transfer signal employing a repeating time frame during the power transfer phase where the frame comprises at least a power transfer time interval and a foreign object detection time interval. The power receiver comprises a synchronizer (311) which synchronizes a local time reference to the repeating time frame and a load controller (309) which disconnects a load (303) during at least part of the foreign object time detection time intervals during at least part of the power transfer phase. The timing of the disconnecting is dependent on the local time reference. A mode controller (313) switches between a first operational mode and a second operational mode for the power transfer time intervals in response to a reliability measure for the synchronization.

Abstract: Power loss is calculated in an inductive power transfer system comprising a power transmitter for transmitting power inductively to a power receiver via transmitter coil and receiver coil. The power transmitter obtains time information for time alignment to enable the power transmitter to align the time of calculating the power loss with the power receiver. Power loss is calculated during power transfer according to the obtained time information and received power parameter communicated from the power receiver.