Abstract: The disclosed computer-implemented method may include transmitting, by at least one radar device, to at least one transponder located within a physical environment surrounding a user, a frequency-modulated radar signal that has a first type of polarization, and receiving, by the at least one radar device, signals that have a second type of polarization, the second type of polarization being different than the first type of polarization, detecting, by a processing device communicatively coupled to the at least one radar device, a signal that has the second type of polarization and was returned to the at least one radar device from the at least one transponder in response to the frequency-modulated radar signal, and calculating, by the processing device, a distance between the at least one transponder and the at least one radar device. Various other methods, systems, and computer-readable media are also disclosed.

Abstract: The disclosed apparatus may include at least one transponder that (1) is located on a wearable device worn by a user and (2) retransmits signals received at the transponder after shifting frequencies of the received signals to a certain frequency range. The apparatus may also include at least one radar device that (1) transmits a frequency-modulated radar signal to the transponder and (2) receives signals whose frequencies are within the certain frequency range. In addition, the apparatus may include a processing device that (1) detects a signal returned to the radar device from the transponder, (2) calculates, based on the returned signal, a distance between the transponder and the radar device, and then (3) determines, based on the distance between the transponder and the radar device, a current physical location of at least a portion of the user. Various other apparatuses, systems, and methods are also disclosed.

Abstract: A radar system may include a wearable device dimensioned to be worn by a user of an artificial reality system. The radar system may also include at least one radar device that is secured to the wearable device and transmits at least one frequency-modulated radar signal to at least one transponder located within a physical environment of the user. The radar system may further include at least one processing device communicatively coupled to the radar device. The processing device may detect a signal returned to the radar device from the transponder in response to the frequency-modulated radar signal and then calculate, based at least in part on a frequency of the returned signal, a distance between the transponder and the radar device. Various other devices, systems, and methods are also disclosed.

Abstract: The disclosed computer-implemented method may include transmitting, by at least one radar device, a frequency-modulated radar signal to at least one transponder located within a physical environment surrounding a user, detecting, by a processing device communicatively coupled to the at least one radar device a signal returned to the at least one radar device from the at least one transponder in response to the frequency-modulated radar signal, determining a beat frequency of the returned signal by performing a zero-crossing analysis of the returned signal in the time domain, and calculating, based at least in part on the beat frequency of the returned signal, a distance between the at least one transponder and the at least one radar device. Various other methods, systems, and computer-readable media are also disclosed.

Abstract: The disclosed apparatus may include at least one radar device that transmits a frequency-modulated radar signal to a plurality of transponders located on a wearable device worn by a user. The apparatus may also include a processing device that (1) directs at least one of the plurality of transponders to be in an active state that enables the transponder to receive and transmit signals, (2) detects, while the transponder is in the active state, a signal returned to the radar device from the transponder in response to the frequency-modulated radar signal, (3) calculates, based at least in part on the returned signal, a distance between the transponder and the radar device, and (4) determines, based at least in part on the distance between the transponder and the radar device, a current physical location of at least a portion of the user. Various other apparatuses, systems, and methods are also disclosed.