Systems and methods of identifying motion of a subject

A system for monitoring movements of a subject spaced apart from and out of contact with an electronic device, the system comprising:

• at least one processor;
• and
• at least one memory device operably coupled to the at least one processor and storing processor instructions that, when executed by the system via the at least one processor, cause the system to perform operations comprising:
• transmitting sound energy toward the subject using a first transducer operatively coupled to the electronic device, wherein the first transducer is configured to generate sound energy over a range of frequencies that includes frequencies less than 20 kHz, wherein transmitting sound energy toward the subject comprises emitting a plurality of audio chirps from the first transducer, and wherein individual audio chirps linearly sweep from a first frequency to a second, higher frequency over a predetermined time duration;
• receiving echoes from the subject corresponding to the transmitted sound energy using a second transducer operatively coupled to the electronic device, wherein the second transducer is configured to produce electrical signals corresponding to the received echoes;
• generating a waveform using the electrical signals;
• and
• detecting a plurality of peaks in the waveform, wherein individual peaks have a corresponding amplitude, and further wherein individual peaks are indicative of breathing motion of the subject.