COVID-19 Contact Tracing Using Low Calibrated Transmission Power from BLE—Approach and Algorithm Experimentation

Within a short period of time, the highly infectious COVID-19 virus has progressed into a pandemic which has forced countries to develop contact tracing solutions for closer monitoring of its further spread into the society. Bluetooth low energy (BLE) has been extensively adopted to implement contact tracing focusing mainly on utilizing received signal strength indicator (RSSI) for its distance estimation toward close contact identification (CCI). Nevertheless, when observed closely, many of these solutions were not able to accurately carry out the contact tracing as required by Centers for Disease Control (CDC) and Prevention. The provisions set were distance of within 6-ft (~ 2 m) and period of no less than 15 min for close contact identification. This is mainly because usage of RSSI is highly unstable and volatile. In closing the gap, we proposed a novel approach that utilizes low calibrated transmission power (Tx) employing nRF52832 BLE chipset as wearables, in which, at a distance of greater than 2 m, no close contact will be detected making the accuracy to high and low error distance estimation under ideal condition. Algorithm in establishing close contacts is also demonstrated with complete experimentation. Results show that our proposed solution has maximum error of 0.3209 m in distance estimation of 2 m and 71.43% accuracy in CCI with 4 devices and distance of 2 ± 0.3 m consideration.