| 摘要 |
A security system using infrared rays is provided to prevent interference between infrared signals of adjacent light transmitting units by generating the infrared signals in different waveforms according to channels. A security system using infrared rays includes a light transmitting unit for generating and radiating infrared rays and a light receiving unit for sensing an invader by using the infrared rays of the light transmitting unit. The light transmitting unit comprises an on-block and an off-block of a predetermined period. In the on-block, the infrared signals including a plurality of square pulses are generated by repeating on-duration and off-duration. The light receiving unit synchronizes the received infrared signals with each channel pattern signal and generates an invasion signal by processing the selected channel pattern signal when the off-time exceeds the predetermined period. |
