1. Field of the Invention
The present invention relates to an automatic identification technology that uses radio signals to identify and track objects, and more particularly, to a long range Radio Frequency IDentification (RFID) tracking and powering method and apparatus/system employing Ultra-wideband signaling.
2. Description of Related Art
Radio Frequency IDentification (RFID) is an automatic identification technology that uses radio signals to identify and track objects. Although many types of short-range RFID systems are available for inventory management and tracking of high-value items, most fall short in critical areas: range of operation (commercially available passive RFID tags operate over very short ranges), power consumption (active tags require batteries), cost, size, and security.
Conventional RFID systems—like those used by automated toll systems—include a reader that is both a transmitter and a receiver, and target tags. The reader communicates with the tags using narrowband radio signals. The tags store a serial number and perhaps other data and are attached to an antenna that transmits identification information to the reader. Most commercially available tags require an energy source, such as batteries, which are expensive, have a limited lifetime, and must be replaced periodically. Current commercial tags that are passive are highly range limited. Further, the narrowband signals that carry the identification data cannot penetrate some materials, including walls, dirt, or metal; most have short ranges (less than 2 meters); and they cannot operate in cluttered environments, such as warehouse full of metal shelving. Other commercially available RFID systems that use narrowband frequencies are vulnerable to interception and detection, making them unsuitable for most military and high security applications.
Accordingly, a need exists for an ultra wideband RFID method and system that utilizes passive (i.e., non-battery-operated) Ultra-Wideband (UWB) powering configurations at relatively long ranges in detection friendly as well as harsh and cluttered environments. The present invention is directed to such a need.