Wireless transmitting/receiving system, wireless receiving device and wireless transmitting/receiving method

A wireless transmitting/receiving system includes a transmitter, a first directional receiver, a camera, a storage device and a processor. The transmitter is disposed on a target object and transmits a wireless signal. The first directional receiver is disposed with respect to an entry/exit boundary. The first directional receiver receives the wireless signal and generates a first received signal strength indication. The camera captures an image of the entry/exit boundary. The storage device stores a mapping table of target object location and received signal strength. The processor is electrically connected to the storage device and determines a location of the target object and a moving direction of the target object with respect to the entry/exit boundary according to the image and the mapping table.