Position identification system

Claim 2

A position identification system, comprising: a passive unit, said passive unit consisting essentially of a memory in which a location of said passive unit is stored as digitally-encoded data, a transceiver for receiving a request signal, and thereupon transmitting a response signal comprising said digitally-encoded data modulated on a carrier wave, a processor connected to said memory and transceiver for controlling transmission of said response signal in accordance with receipt of said request signal, and a display connected to said processor for providing a visual indication of the information in said memory; and an active unit, said active unit consisting essentially of, a transceiver for transmitting said request signal to said passive unit, and for receiving said response signal and de-modulating said digitally-encoded data from said carrier wave, a processor connected to said transceiver for downloading said digitally encoded data therefrom, a keyboard connected to said processor for allowing operator entry of selection criteria; a memory connected to said processor for storing said selection criteria, whereby said processor compares said digitally-encoded data with said selection criteria, a display connected to said processor for displaying said digitally encoded data to an operator; whereby said active unit transmits said request signal to said passive unit and said passive unit transmits said digitally-encoded data in response, and said active unit receives said digitally-encoded data, compares said digitally-encoded data to said selection criteria, and displays said location of said passive unit to said operator in real-time for navigational assistance in accordance with said selection criteria.

Claim 3

A position identification system according to claim 1, wherein said passive unit further comprises a battery for providing power thereto.

Claim 4

A position identification system according to claim 2, wherein said passive unit further comprises a solar cell for providing power and for providing a charging current to said battery.

Claim 5

A position identification system, comprising: a plurality of passive units arranged in a geographical network, said passive units each further comprising, a memory in which a location of said passive unit is stored as digitally-encoded data, a transceiver for receiving a request signal, and thereupon transmitting a response signal comprising said digitally-encoded data modulated on a carrier wave, a processor connected to said memory and transceiver for controlling transmission of said response signal in accordance with receipt of said request signal; and an active unit, said active unit further comprising, a transceiver for transmitting said request signal to said passive units, and for receiving said response signal from each passive unit within range and de-modulating said digitally-encoded data therefrom, a keyboard for allowing operator entry of selection criteria; a memory for storing said digitally-encoded data and said selection criteria, a processor connected to said transceiver, keyboard and memory for downloading said digitally encoded data and selection criteria from the respective transceiver and keyboard, and for controlling storage of said digitally-encoded data and said selection criteria in said memory, a display connected to said processor for displaying said digitally encoded data to an operator in real time; whereby said active unit transmits said request signal to said passive units and all passive units within range transmit said digitally-encoded data in response, and said active unit receives said digitally-encoded data, said processor being selectively operable in any one of two separate modes for comparing said digitally-encoded data with said selection criteria, said modes including a main mode wherein said active unit receives said digitally-encoded data from each of said passive units within range and displays said digitally encoded data to said operator in real time, and a selective mode wherein said active unit receives said digitally-encoded data from each of said passive units within range, compares said digitally-encoded data to said selection criteria, and displays said digitally-encoded data from one of said passive units selected in accordance with said selection criteria.

Claim 6

A position identification system, comprising: a plurality of passive units arranged in a geographical network, said passive units each further comprising, a memory in which a location of said passive unit is stored as digitally-encoded data, a transceiver for receiving a request signal, and thereupon transmitting a response signal comprising said digitally-encoded data modulated on a carrier wave, a processor connected to said memory and transceiver for controlling transmission of said response signal in accordance with receipt of said request signal; and an active unit, said active unit further comprising, a transceiver for transmitting said request signal to said passive units, and for receiving said response signal from each passive unit within range and de-modulating said digitally-encoded data therefrom, a keyboard for allowing operator entry of selection criteria; a memory for storing said digitally-encoded data and said selection criteria, a processor connected to said transceiver, keyboard and memory for downloading said digitally encoded data and selection criteria from the respective transceiver and keyboard, and for controlling storage of said digitally-encoded data and said selection criteria in said memory, a display connected to said processor for displaying said digitally encoded data to an operator in real time; whereby said active unit transmits said request signal to said passive units and all passive units within range transmit said digitally-encoded data in response, and said active unit receives said digitally-encoded data, said processor being selectively operable in any one of two separate modes for comparing said digitally-encoded data with said selection criteria, said modes including a main mode wherein said active unit receives said digitally-encoded data from each of said passive units within range and displays said digitally encoded data to said operator in real time, and a selective mode wherein said active unit receives said digitally-encoded data from each of said passive units within range, compares said digitally-encoded data to said selection criteria, and displays said digitally-encoded data from one of said passive units selected in accordance with said selection criteria.

Claim 7

A position identification system, comprising: a mobile passive unit attached to a person, place or thing to allow tracking thereof, said passive unit consisting essentially of a memory in which a location of said passive unit is stored as digitally-encoded data, a transceiver for receiving a request signal, and thereupon transmitting a response signal comprising said digitally-encoded data modulated on a carrier wave, a processor connected to said memory and transceiver for controlling transmission of said response signal in accordance with receipt of said request signal; and an active unit for tracking said passive unit, said active unit consisting essentially of, a transceiver for transmitting said request signal to said passive unit, and for receiving said response signal and de-modulating said digitally-encoded data from said carrier wave, a processor connected to said transceiver for downloading said digitally encoded data therefrom, a keyboard connected to said processor for allowing operator entry of selection criteria; a memory connected to said processor for storing said selection criteria, whereby said processor compares said digitally-encoded data with said selection criteria, a display connected to said processor for displaying said digitally encoded data to an operator; whereby said active unit transmits said request signal to said passive unit and said passive unit transmits said digitally-encoded data in response, and said active unit receives said digitally-encoded data, compares said digitally-encoded data to said selection criteria, and display said location of said passive unit to said operator in real-time for navigational assistance in accordance with said selection criteria.

Claim 8

A position identification system, comprising: a mobile passive unit attached to a person, place or thing to allow tracking thereof, said passive unit consisting essentially of a memory in which a location of said passive unit is stored as digitally-encoded data, a transceiver for receiving a request signal, and thereupon transmitting a response signal comprising said digitally-encoded data modulated on a carrier wave, a processor connected to said memory and transceiver for controlling transmission of said response signal in accordance with receipt of said request signal; and an active unit for tracking said passive unit, said active unit consisting essentially of, a transceiver for transmitting said request signal to said passive unit, and for receiving said response signal and de-modulating said digitally-encoded data from said carrier wave, a processor connected to said transceiver for downloading said digitally encoded data therefrom, a keyboard connected to said processor for allowing operator entry of selection criteria; a memory connected to said processor for storing said selection criteria, whereby said processor compares said digitally-encoded data with said selection criteria, a display connected to said processor for displaying said digitally encoded data to an operator; whereby said active unit transmits said request signal to said passive unit and said passive unit transmits said digitally-encoded data in response, and said active unit receives said digitally-encoded data, compares said digitally-encoded data to said selection criteria, and display said location of said passive unit to said operator in real-time for navigational assistance in accordance with said selection criteria.