US Patent No. 10,893,488

RADIO FREQUENCY (RF) POWER BACK-OFF OPTIMIZATION FOR SPECIFIC ABSORPTION RATE (SAR) COMPLIANCE


Patent No. 10,893,488
Issue Date January 12, 2021
Title Radio Frequency (rf) Power Back-off Optimization For Specific Absorption Rate (sar) Compliance
Inventorship Charbel Khawand, Redmond, WA (US)
Sean Russell Mercer, Issaquah, WA (US)
Mahesh M. Pai, Sammamish, WA (US)
Assignee Microsoft Technology Licensing, LLC, Redmond, WA (US)

Claim of US Patent No. 10,893,488

1. A method comprising:detecting a specific absorption rate (SAR) trigger at a mobile computing device indicative of potential for non-compliance with SAR legal limits;
determining current signal conditions of the mobile computing device, the current signal conditions including a current radio-frequency (RF) transmission power of one or more antennas of the mobile computing device for communicating with one or more base stations;
predicting future signal conditions of the mobile computing device using a prediction model, the prediction model including a predicted RF transmission power for maintaining the communication of the one or more antennas of the mobile computing device with the one or more base stations over a future period of time and for satisfying the SAR legal limits over the future period of time, the prediction model configured to derive a predicted change over the future period of time in a received signal strength indicator (RSSI) detectable at the one or more base stations based on analysis of historical usage data for the mobile computing device; and
adjusting the RF transmission power of the one or more antennas of the mobile computing device a selected amount in response to detecting the SAR trigger, the selected amount based on the determined current signal conditions and the predicted future signal conditions.