SINGLE TRANSACTION AOA/TOA/DOPPLER TAGGING TRACKING AND LOCATING

摘要

With respect to electronic tag location and tracking, this invention solves moving target and two-fold angle ambiguity without the use of bulky antenna arrays. A multi-element antenna system with fore and aft placement of the elements separated by about ¼ to ½ wave provides an angle of arrival. Antenna selection treats the multiple elements as a single electronically translatable element with an omnidirectional pattern. The elements may be oriented to line up with the fuselage of an aircraft. The antenna elements may be skewed from fore to aft to resolve ambiguity observed with static targets. The apparatus uses successive packets whose content is known at the platform's receiver so that the signal correlation functions are directly comparable. Identical successive packets or different packets of the same length and from the same sequence family may be used. The system may be rapidly calibrated with existing system components.

主权项

1. Apparatus for accurately locating a tag, including a moving tag, transmitting packets of information at a packet rate using phase-coherent signaling on a carrier frequency, the apparatus comprising:
at least two antenna elements having fore and aft positions relative to a tag to be located; wherein the antenna elements are spaced apart by about a ¼ to ½ wave of the carrier frequency; electronic circuitry receiving signals from the antenna elements, the electronic circuitry being operative to correlate the signals to determine an angle of arrival (AOA) and the difference in the distance to the tag from each antenna position.