US Patent 11711638 Audience monitoring systems and related methods

Audience monitoring systems and related methods are described herein. An example audience monitoring system includes a beacon to be disposed proximate a media presentation device. The beacon is to transmit a ping signal. The system also includes a portable metering device to be carried by a person. The portable metering device includes a microphone to receive an audio signal and a processor to determine a distance value indicative of a distance between the portable metering device and the beacon based on the ping signal.