Patent ID: 11914093
Assignee: MICROSOFT TECHNOLOGY LICENSING, LLC
Field: Measurement (Instruments)
Classification: CPC G  H | IPC G

Claim 15:
16. A computing device, comprising:
a logic subsystem; and
a storage subsystem holding instructions executable by the logic subsystem to:
drive each of a plurality of radio frequency (RF) antennas to expose a body surface of a human user to an E-field, wherein at least part of a face of the human user is positioned within a near-field region relative to the plurality of RF antennas;
scan each of the plurality of RF antennas to individually determine ground-relative changes in electrical conditions for each of the plurality of RF antennas relative to a previous time frame;
select a differential-scanning subset of RF antennas from among the plurality of RF antennas, including two or more RF antennas for which the ground-relative changes in electrical conditions exceed a frame-to-frame threshold;
for each RF antenna in the differential-scanning subset, determine a set of antenna-relative changes in electrical conditions by comparing the RF antenna to one or more other RF antennas in the differential-scanning subset as a plurality of pairs; and
based at least in part on the ground-relative changes in electrical conditions and the antenna-relative changes in electrical conditions, classify a movement performed by the human user as a recognized facial expression of a plurality of predefined facial expressions.