Real-time locating systems (RTLS) is used to identify as well as to track the location of objects or people in real time, within a building or other available area. Wireless RTLS tags are attached to objects that are worn by people and in most of the RTLS, fixed reference points receives wireless signals from tags to determine their particular location. Examples of real-time locating systems consist of tracking automobiles through an assembly line, location of the pallets of merchandise in a warehouse, or getting medical equipment in a hospital. Most of the wireless technologies are mainly used to establish the communication between tags and readers. Most popular ones are Wi-Fi, GPS, Infrared, Bluetooth, and active and passive RFID systems. After positioning the readers at fixed locations in a given limited environment, the location of the mobile tags are usually determined by the analysis of the various aspects of the communications between readers and tags. The choice of a method depends on the application requirements. The physical layer of RTLS technology is usually some form of radio frequency (RF) communication, but some systems use optical (usually infrared) or acoustic (usually ultrasound) technology instead of or in addition to RF.