Method, system and computer program product for distance determination between persons

A system for determining a distance between persons, comprising:

• a plurality of devices, each associated with a person and each comprising a battery, ultra-wideband (UWB) tag and UWB anchor, the battery configured to power the UWB tag and the UWB anchor and wherein the UWB anchor is substantially disabled;
• wherein each of the plurality of devices is configured to periodically or quasiperiodically repeat a typical operating pattern;
• the typical operating pattern configured for:
• enabling the UWB anchor during an announcing period;
• transmitting an announcing signal of the UWB tag comprising an indication of a transmission time;
• and
• transmitting a ranging signal at the transmission time;
• wherein a second device is configured to initiate an atypical operating pattern when an announcing signal from a first device is received on the second device during an announcing period of this second device;
• the atypical operating pattern configured for:
• determining an anchor wake-up period for the second device based on the transmission time of the received announcing signal;
• enabling the UWB anchor of the second device during the determined anchor wake-up period;
• and
• receiving the ranging signal on the second device during the determined anchor wake-up period;
• wherein the system is configured to determine a distance between the first device and the second device based on the ranging signal from the first device received on the second device.

A computer program product for determining a distance between persons, wherein a plurality of devices is provided, each associated with a person and each comprising a battery, ultra-wideband (UWB) tag and UWB anchor, the UWB tag and the UWB anchor being energized by the battery and the UWB anchor being substantially disabled;

• wherein the computer program product comprises instructions for periodically or quasiperiodically repeating a typical operating pattern on each of the plurality of devices;
• the typical operating pattern comprising:
• enabling the UWB anchor during an announcing period;
• transmitting an announcing signal of the UWB tag comprising an indication of a transmission time;
• and
• transmitting a ranging signal at the transmission time;
• wherein the computer program product comprises instructions for initiating an atypical operating pattern on a second device when an announcing signal from a first device is received on the second device during an announcing period of this second device;
• the atypical operating pattern comprising:
• determining an anchor wake-up period for the second device based on the transmission time of the received announcing signal;
• enabling the UWB anchor of the second device during the determined anchor wake-up period;
• and
• receiving the ranging signal on the second device during the determined anchor wake-up period;
• wherein the computer program product comprises instructions for determining a distance between the first device and the second device based on the ranging signal from the first device, which is received on the second device.