摘要 |
<p>A tracking system includes a network; a plurality of signal sources communicatively coupled to the network, the plurality of signal sources configured to transmit substantially identical signals; and an RFID tag configured to receive the substantially identical signals from the plurality of signal sources, determine points of intersection from hyperbola curves defining phase differences between the substantially identical signals, a point of intersection of three hyperbola curves defining a location of the user device. In some embodiments, the plurality of signal sources comprise a single transmitter and a predetermined plurality of substantially identical antennas coupled to the single transmitter by cables of a substantially same length.</p> |