Today the U.S. Patent and Trademark Office officially granted Apple a patent that relates to detecting presence based on audio.
Apple's granted patent covers a process and system that can determine if two (or more) devices and users are within an audible zone (e.g., within the same room) based on audio. Based on whether the devices and users are within an audible zone, the devices can automatically modify the manner in which it processes audio. This can be beneficial for many reasons.
For example, multiple users can be on a conference call with each other. In such a case, two or more users can be in communication with each other through, for example, mobile devices and/or headphone sets. At a first point in time, a second user can enter a building that a first user is in, both being on the same call. At some point during the call, the second user can enter the same room as the second user.
As the two users get closer, the first user may be able to hear voice of the second user directly through physical space (as well as through the first user's device). At this point, it may be desirable to turn down or turn off the second user's voice heard through speakers of the first user's device.
Depending on the latency of the communication network, there can be a recognizable delay between the playback of the second user's speech through the first user's device and the arrival of the second user's speech to the first user's ears through physical space.
This delay can create an unpleasant echo effect for the first user. Thus, it may be beneficial for the first user's mobile device to be able to detect the proximity of the second user and modify the processing of the audio signal (e.g., attenuate or "turn off" the audio signal) coming from the second user, when it is determined that the first user is close enough to the second user that the first user can hear the second user through physical space.
Apple's patent FIG. 6 below illustrates a use case for detecting presence based on audio; FIG. 2 illustrates a system with echo canceler for detecting presence based on audio.
For more details, review Apple's granted patent 11,146,909.