Wireless Visitors Counter Using Arduino

The Wireless Visitors Counter system operates by detecting individuals passing through a monitored entrance and wirelessly relaying the updated tally to a display unit. At the detection site, an infrared (IR) sensor emits a beam of light towards a receiver. When a person walks through the doorway, the IR beam is temporarily broken, causing a change in the analog voltage level from the sensor. This analog signal is conditioned by an LM358 operational amplifier to ensure a clean, reliable digital threshold transition. The processed signal is then read by the Arduino Uno board, which maintains the running count of visitors. To transmit this data without wires, the count is fed into an HT12E encoder IC, which serializes the parallel data bits into a format suitable for the 434MHz RF transmitter module. On the receiving end, the 434MHz RF receiver module captures the transmitted radio frequency signals and passes them to an HT12D decoder IC. The decoder reverses the encoding process, converting the serial data back into parallel signals that represent the visitor count. Finally, the receiving circuitry interfaces with a 16x2 character LCD screen to visually present the real-time occupancy data to the user, allowing for seamless remote monitoring.