The present invention discloses a tracking apparatus and system thereof, useful for objects affixed with a smart tags entering and exiting an enclosed area through a gate. A gate consists of two directional antennas directed respectively inward and outward from the gate crossing line and connected to an RF beacon. Each smart tag affixed to an object approaching the gate area, receives a transmission of ID associated with each directional antenna. The smart tag detects crossing of the gate line and direction of crossing by method of processing the ID of the two directional antennas. The detected crossing data is transmitted via a wireless communication link, to a base station located at the enclosed zone. The base station transmits the gate detection data to a service center.