Zhang Chun-hua, Xie Yong-jun, Zhou Zheng-yi, et al. Design of People Counting Systems in Public Areas[J]. 2012, 29(3): 63-67.DOI: 10.3969/j.issn.1007-7162.2012.03.012.
With passive infrared pyroelectric sensors and ultrasonic sensors as the detecting element
and the STM8S105C4 microcontroller as the core controller
the direction and number of traffic foot are detected. The data communication at all entrances and exits and the counting of people in public areas are conducted through the NRF24L01 wireless module.