Bluetooth Beacon in Check-in and Attendance Application

1.      Bluetooth beacon introduction

BLE Beacon is a hardware device based on the Bluetooth low energy (Bluetooth 4.0 and above) broadcast protocol. As a BLE device, it is usually installed in a specific location indoors. As the reference point of the indoor location, it continuously broadcasts to the surrounding environment. It does not need to be connected to any host device, but only needs to be scanned and analyzed by the host device. The Bluetooth beacons produced by HYXKIOT have the following features:

a.      Low power consumption, long standby time, no external power supply required;

b.      Easy to install. Use 3M glue to install;

c.       Lower cost and reduced project budget;

d.      It has high compatibility and adaptability and can be used with most models on the market.

2.      What is the relationship between Bluetooth beacon distance and signal strength RSSI

d=10^((ABS(RSSI)-A)/(10*n)) ———- (1)

d is the distance,unit is m.

RSSI is the signal strength of the Bluetooth beacon received by the mobile phone, which is a negative number.

A is the absolute value of the RSSI value received when the mobile phone is 1m away from the Bluetooth beacon.

n is the environmental attenuation factor, which needs to be tested and corrected.

The following figure is a graph based on A=63, n=1.56:

We can see from the above figure, RSSI and distance have a nonlinear relationship. When the distance exceeds 8 meters, the change of RSSI with distance is not obvious.

3.      Introduction of check-in and attendance based on Bluetooth beacon

When we use the mobile APP for check-in and punch-in, due to differences in the received signal strength of different mobile phones, signal occlusion, signal reflection, etc., we cannot simply reduce the signal strength of the bluetooth beacon or use the signal strength of a single measurement (RSSI ), our recommendations are as follows:

a.      Through the actual test, according to the punching distance required by the business, the corresponding signal strength value is actually tested, and the signal strength is filtered in the WeChat applet or mobile APP.

b.      Perform multiple signal measurements, and take the one with the strongest signal strength as the operation basis (because of occlusion and other reasons, the signal will only become weaker, not stronger, so the reliability of the strong signal strength is higher).

4. Practical application of HYXKIOT beacon in check-in and attendance

HYXKIOT's Bluetooth beacons HY-KTB801, HY-KTB801E are widely used in the following application scenarios:

Bluetooth beacon and Bluetooth + NB-IOT work card are used to automatically punch in. When the Bluetooth work card scans the signal of the Bluetooth beacon, it is sent to the background server through NB-IOT for punching.

Use the Bluetooth beacon combined with the mobile APP to punch in.

The Bluetooth beacon triggers the body camera, and when the body camera reaches the vicinity of the Bluetooth beacon, the camera function is automatically turned on.

The Bluetooth beacon triggers other applications. When entering a certain distance near the Bluetooth beacon, a specific operation is automatically triggered (such as broadcasting a product introduction, etc.)