COVID-19 contact tracing is one of preventive solution to slow down the spread of the virus. Some of countries have been implementing manual contact tracing and also digital tracing using smartphone application. The success of the digital tracing implementation requires cooperation from the community and firm leadership from the government as well as medical record reporting from the public health so that the data can be analyzed as soon as possible for the next preventive action required. However, for countries with large population like Indonesia, it is difficult to control the society while the health facilities are quite overwhelmed enough to cope with the number of infected, which has not decreased to date. Proximity-based COVID-19 contact tracing system devices using BLE (Bluetooth Low Energy) technology is focusing on tracing and controlling the spread of virus in local community. For example, the system devices will be implemented in a factory, the devices are put in front pocket of factory employee' shirt or hooked on the shirt. The devices will record the proximity between employees and the data is synchronized using their smartphone or via application to be stored in database. The proximity records will be used once there is an infected employee to obtain information of possibility of other employees are being infected, to avoid massive test and isolation. In addition, the use of this device can be expanded even further.

COVID-19 contact tracing is a preventive solution to slow the spread of the virus. Several countries have implemented manual contact tracing as well as digital tracking using smartphone applications. A proximity-based COVID-19 contact tracing system device using BLE (Bluetooth Low Energy) technology focuses on tracking and controlling the spread of the virus in local communities. The devices consist of a signal sending device (tag) and a signal receiving device (scanner). Suppose a system device is implemented in a factory. The tag will be used by employees by placing it in the front pocket of the factory employee's clothes or hooked on the shirt. The tag will continuously send a signal that will be read by the scanner. This received signal with the received signal strength indicator (RSSI) format will be used to calculate the distance between the scanner and the tag. Then the distance will be used to determine the coordinate point of the tag, with calculations using the trilateration algorithm. Therefore, the distance between tags can be obtained, while with signal fluctuation, the actual coordinate point cannot be obtained, yet proximity information can still be obtained by filtering distance data at a specified time interval that is less than the threshold value of the distance, 2 meters, then comparing the data with the overall data, resulting in a percentage value. A high percentage, above 80%, indicates the closeness between tags.