Distributed network for multi-lateration with circularly polarized antenna for hemispherical coverage

A system for identifying the geographical locations of objects having tags containing transmitters, a respective tag's transmitter being operative to transmit signals containing information identifying its associated tag, comprising:

• a plurality of geographically dispersed receivers having known geographical positions, and being operative to receive signals transmitted from one or more of said tags;
• a plurality of detection processors coupled to said receivers, and being operative to process signals received thereby to identify earliest time-of-arrival signals received from a tag, a respective detection processor being operative to transmit a respective message, containing the identification of a tag and the earliest time-of-arrival of signals received therefrom by a receiver to which said each detection processor is coupled, over a communication framework to a selected one of a plurality of association processors, such that messages transmitted by detection processors for the same tag are transmitted to the same association processor;
• each association processor being operative to store contents of messages received from one or more detection processors as a respective association report for a respective tag, and to transmit association reports over said communication framework to a plurality of location processors;
• and wherein
• each location processor is operative to determine the geographical location of tags identified in association reports received thereby, in accordance with time-of-arrival information for said tags contained in said association reports.

A distributed data processing system for use with a geo-location system for identifying geographical locations of objects having tags containing transmitters, a respective tag's transmitter being operative to transmit signals containing information identifying its associated tag, and including a plurality of geographically dispersed receivers having known geographical positions, and being operative to receive signals transmitted from one or more of said tags, said system comprising

• a plurality of detection processors, partitioned among said plurality of geographically dispersed receivers, and being coupled to derive, from signals received by a receiver coupled thereto, times-of-arrival of earliest detectable portions of tag transmissions and tag identification information data contained therein, and wherein a respective detection processor is operative to transmit, over a communication framework to one of a partitioned set of association processors, a tag detection report containing the time-of-arrival of and tag identification information within a received transmission for a single tag;
• a respective association processor being operative to store received messages from one or more detection processors and to transmit association reports for respective tags over said communication framework to one of a partitioned set of location processors, such that an association report for a given tag is transmitted to one location processor;
• and wherein
• a respective location processor is operative to determine the geographical location of a tag using time-of-arrival information derived from information in association reports derived from messages from said detection processors associated with said tag.