Abstract: This disclosure provides systems, methods and apparatus for mitigating electromagnetic radiation emissions. In one aspect, a power transfer device of a wireless electric vehicle charging (WEVC) system is provided. The power transfer device includes a ferrite material and at least one electrically conductive coil. The ferrite material and the at least one coil are configured to wirelessly transfer energy either from or to a second power transfer device of the WEVC system. The power transfer device further includes at least one shield comprising a plurality of electrically conducting regions and one or more electrically insulating regions. The plurality of electrically conducting regions and one or more electrically insulating regions are configured to mitigate electromagnetic radiation emissions from the WEVC system that do not contribute to the wireless power transfer between the at least one electrically conductive coil and the second power transfer device.

Abstract: Systems, methods, and devices of the various embodiments enable local visual identification and verification of robotic vehicles. Various embodiments may enable disambiguation of a robotic vehicle from among a plurality of robotic vehicles.

Abstract: Certain aspects of the present disclosure propose methods for determining power level of one or more transmitters based on a power level of a primary transmitter when the transmitters are located in close proximity of each other. The power levels may be determined such that a combined power of all the transmitters is compliant with regulatory radio frequency (RF) safety requirements. For certain aspects, power level of the lower priority transmitters may be determined utilizing one or more look-up tables. For another aspect, power level of the lower priority transmitters may be calculated using an algorithm based on the power level of the priority transmitter. In aspects, the power level of lower priority transmitters and the time duration for which the transmitters are active may be selected dynamically so that the time averaged power of the transmitters for a defined period of time falls below the RF exposure limit.

Abstract: A device and method for determining power density measurements of electromagnetic (EM) transmissions from an antenna of a wireless electronic device are disclosed. The method can include determining one or more worst case configurations within an exposure plane based on a power density distribution of the antenna in free space. The method can also include measuring power density distribution across a first plane at a first distance from the exposure plane and across a second plane at a second distance from the exposure plane. The method can also include first back transforming power density distribution of the first plane to the second plane, second back transforming power density distribution from the first plane to the exposure plane, and third back transforming power density distribution from the second plane to the exposure plane, for the one or more worst case configurations.

Abstract: A method and apparatus for determining transmit power limits for multiple transmitter devices is provided. The method begins when a two-dimensional area scan and a localized three-dimensional volume scan are performed for each transmitter and antenna. These two-dimensional area scans are converted to a three-dimensional full volume data using analytical estimations to determine the peak averaged SAR value, and subsequently determining the error associated with the analytical estimation. The error associated with the analytical estimation is determined by comparison with the measured value. The combined peak averaged SAR may then be determined for simultaneous transmissions of multiple transmitters with varying transmit powers by combining the scaled and analytically determined three-dimensional full volume data for each transmitter. The value is then further scaled by the worst-case conversion error for all active transmitters.

Abstract: Embodiments disclosed herein provide a method and apparatus for optimizing time-averaged transmitter power of a communications device. A time-averaged SAR is computed over a predefined time window using past transmitter power levels with minimum transmitter power equal to reserve transmitter power for any time interval. Based on the time-averaged SAR a maximum allowable transmitter power for a future fixed time interval is determined. The communication device then transmits at a power equal to or less than the maximum allowable transmitter power. The communication device may back off from high transmitter power to a reserve transmitter power when calculated time-averaged SAR approaches the SAR limit. When old high power transmissions expire, the communication device gains SAR margin and may then transmit at high power. The apparatus comprises: at least one antenna, a transmitter in communication with a power supply, a receiver, a timer in communication with a processor, and a memory.

Abstract: Embodiments disclosed herein provide a method and apparatus for optimizing time-averaged transmitter power of a communications device. A time-averaged SAR is computed over a predefined time window using past transmitter power levels with minimum transmitter power equal to reserve transmitter power for any time interval. Based on the time-averaged SAR a maximum allowable transmitter power for a future fixed time interval is determined. The communication device then transmits at a power equal to or less than the maximum allowable transmitter power. The communication device may back off from high transmitter power to a reserve transmitter power when calculated time-averaged SAR approaches the SAR limit. When old high power transmissions expire, the communication device gains SAR margin and may then transmit at high power. The apparatus comprises: at least one antenna, a transmitter in communication with a power supply, a receiver, a timer in communication with a processor, and a memory.

Abstract: This disclosure provides systems, methods and apparatus for assessing electromagnetic exposure. In one aspect an apparatus is provided. The apparatus includes at least a first circuit configured to calculate electromagnetic exposure of at least a portion of at least one human in proximity to a wireless electric vehicle charging system. The portion of the at least one human is modeled by at least one homogeneous phantom model having dielectric properties that are representative of human tissue. The apparatus further includes at least a second circuit configured to scale the calculated electromagnetic exposure to simulate an electromagnetic exposure based on an inhomogeneous anatomical model of the portion of the at least one human.

Abstract: Methods and apparatus are disclosed for wirelessly transmitting power. In one aspect, an apparatus for wireless transmitting power is provided. The apparatus comprises a first coil loop defining a first area, the first coil loop conducting current at a first current value for generating a first magnetic field. The apparatus further comprises a second coil loop surrounding the first coil loop and defining a second area, the second coil loop conducting current at a second current value generating a second magnetic field, wherein a ratio of the first current value to the first area is substantially equal to a ratio of the second current value to the second area.

Abstract: Embodiments described herein provide a method and apparatus for determining a maximum transmitter power for a mobile device. First, a maximum specific absorption rate (SAR) value is determined. Then, a maximum transmitter power based on the maximum SAR value is determined. The maximum SAR value may be determined using any or all of the following methods: using a composite worst-case SAR map, determining a usage position of the mobile device, and a running average of transmitter power. A further embodiment provides an apparatus for managing transmitter power. The apparatus includes a modem that is in communication with a transmitter; a processor in communication with the modem; and a memory in communication with the processor.

Abstract: A method and apparatus for avoiding transmit power limitations due to specific absorption rate (SAR) constraints. The method maximizes transmit power by transmitting on a first transmitter for a first period of time, second transmitter for a second period of time, through an Nth transmitter for an Nth period of time. The transmission time periods may or may not overlap, and the SAR distributions may or may not overlap. The transmitters may or may not transmit at different frequencies and may or may not share antennas. The average transmit power may be reduced by the number of transmitters that are periodically transmitting. The period of transmission for a given transmitter may be inversely proportional to the measured SAR for that particular transmitter.

Abstract: A method and apparatus for determining transmit power limits for multiple transmitter devices is provided. The method begins when a two-dimensional area scan and a localized three-dimensional volume scan are performed for each transmitter and antenna. These two-dimensional area scans are converted to a three-dimensional full volume data using analytical estimations to determine the peak averaged SAR value, and subsequently determining the error associated with the analytical estimation. The error associated with the analytical estimation is determined by comparison with the measured value. The combined peak averaged SAR may then be determined for simultaneous transmissions of multiple transmitters with varying transmit powers by combining the scaled and analytically determined three-dimensional full volume data for each transmitter. The value is then further scaled by the worst-case conversion error for all active transmitters.

Abstract: Efficient techniques for determining compliance of a wireless device with radio-frequency (RF) exposure standards and regulations. In an aspect, two-dimensional surface scans of a device are determined and stored in a memory during a certification phase. Each scan corresponds to a basis surface scan wherein only one transmitter and one antenna of the device are active. During real-time operation, the basis surface scans corresponding to the real-time active transmitters and antennas of the device are retrieved. The retrieved scans are processed according to the real-time operating parameters to determine an estimated RF exposure metric, e.g., a peak specific absorption rate (SAR). The transmit power levels of the device may be adjusted in real time to ensure compliance of the estimated RF exposure metric with applicable standards and regulations.

Abstract: This disclosure provides systems, methods and apparatus for mitigating electromagnetic radiation emissions. In one aspect, a power transfer device of a wireless electric vehicle charging (WEVC) system is provided. The power transfer device includes a ferrite material and at least one electrically conductive coil. The ferrite material and the at least one coil are configured to wirelessly transfer energy either from or to a second power transfer device of the WEVC system. The power transfer device further includes at least one shield comprising a plurality of electrically conducting regions and one or more electrically insulating regions. The plurality of electrically conducting regions and one or more electrically insulating regions are configured to mitigate electromagnetic radiation emissions from the WEVC system that do not contribute to the wireless power transfer between the at least one electrically conductive coil and the second power transfer device.

Abstract: Efficient techniques for estimating specific absorption rate (SAR) for wireless devices. In an aspect, electric and/or magnetic field measurements are made over a two-dimensional (2D) surface in the proximity of a wireless device. The field measurements are used to generate a near-field equivalent source representation of the wireless device. Specific absorption rate over, e.g., a 1 g/10 g mass may then be calculated by performing electromagnetic simulations using the near-field equivalent source representation. In an aspect, an elementary dipole array may be used to generate the near-field equivalent source representation from the field measurements.

Abstract: This disclosure provides systems, methods and apparatus for assessing electromagnetic exposure. In one aspect an apparatus is provided. The apparatus includes at least a first circuit configured to calculate electromagnetic exposure of at least a portion of at least one human in proximity to a wireless electric vehicle charging system. The portion of the at least one human is modeled by at least one homogeneous phantom model having dielectric properties that are representative of human tissue. The apparatus further includes at least a second circuit configured to scale the calculated electromagnetic exposure to simulate an electromagnetic exposure based on an inhomogeneous anatomical model of the portion of the at least one human.

Abstract: Efficient techniques for determining compliance of a wireless device with radio-frequency (RF) exposure standards and regulations. In an aspect, two-dimensional surface scans of a device are determined and stored in a memory during a certification phase. Each scan corresponds to a basis surface scan wherein only one transmitter and one antenna of the device are active. During real-time operation, the basis surface scans corresponding to the real-time active transmitters and antennas of the device are retrieved. The retrieved scans are processed according to the real-time operating parameters to determine an estimated RF exposure metric, e.g., a peak specific absorption rate (SAR). The transmit power levels of the device may be adjusted in real time to ensure compliance of the estimated RF exposure metric with applicable standards and regulations.

Abstract: Efficient techniques for estimating specific absorption rate (SAR) for wireless devices. In an aspect, electric and/or magnetic field measurements are made over a two-dimensional (2D) surface in the proximity of a wireless device. The field measurements are used to generate a near-field equivalent source representation of the wireless device. Specific absorption rate over, e.g., a 1 g/10 g mass may then be calculated by performing electromagnetic simulations using the near-field equivalent source representation. In an aspect, an elementary dipole array may be used to generate the near-field equivalent source representation from the field measurements.

Abstract: A self-test prediction system predicts the impact that a host device has on an embedded wireless device's receiver performance by recording the wireless device's received power. No carrier or pilot signal is necessary to predict the impact. The wireless device's embedded receiver monitors its own received power (e.g., RSSI) from any type of radiated noise from the host device. For receivers that do not provide RSS referenced to absolute power, an external reference tone can be used in order to scale the measured receiver carrier to noise or signal to noise data to an absolute power. The increase in measured received power on the wireless device's receiver correlates to the impact the host device will have on the embedded wireless device's receiver sensitivity performance, providing a faster approach with less external equipment than current approaches that use external equipment to simulate the wireless device's forward link signal.

Abstract: Certain aspects of the present disclosure propose methods for determining power level of one or more transmitters based on a power level of a primary transmitter when the transmitters are located in close proximity of each other. The power levels may be determined such that a combined power of all the transmitters is compliant with regulatory radio frequency (RF) safety requirements. For certain aspects, power level of the lower priority transmitters may be determined utilizing one or more look-up tables. For another aspect, power level of the lower priority transmitters may be calculated using an algorithm based on the power level of the priority transmitter. In aspects, the power level of lower priority transmitters and the time duration for which the transmitters are active may be selected dynamically so that the time averaged power of the transmitters for a defined period of time falls below the RF exposure limit.