Identification system

Claim 2

A passive identification system comprising:

Claim 3

means for generating an electromagnetic field, containing circuit means comprising: a power supply; and a self-resonating power supply oscillator electrically connected to said power supply; and a first coil electrically connected to said power oscillator wherein said power supply activates said self-resonating oscillator for a first time interval, during which first time interval said self-resonating oscillator drives said coil at a first frequency; a plurality of means for transmitting radio frequency radiation separate and spaced from said generating means each including: a second coil for receiving electrical energy from said generating means at a position remote therefrom; and means powered by said second coil for encoding a digital signal and transmitting through said second coil the encoded signal at a second frequency different from said first frequency during a second time interval different from said first time interval, said generating means not delivering electrical energy to said coil means during said second timer interval; and receiving means remote from said transmitting means for receiving the transmitted encoded signal; and decoding means; and comparison means electrically connected to said decoding means and including means for storage of digital data and for comparing the received decoded signal with stored data to identify the specific transmitting means whose signal has been received and compared.

Claim 4

means for generating an electromagnetic field, containing circuit means comprising: a power supply; and a self-resonating power supply oscillator electrically connected to said power supply; and a first coil electrically connected to said power oscillator wherein said power supply activates said self-resonating oscillator for a first time interval, during which first time interval said self-resonating oscillator drives said coil at a first frequency; a plurality of means for transmitting radio frequency radiation separate and spaced from said generating means each including: a second coil for receiving electrical energy from said generating means at a position remote therefrom; and means powered by said second coil for encoding a digital signal and transmitting through said second coil the encoded signal at a second frequency different from said first frequency during a second time interval different from said first time interval, said generating means not delivering electrical energy to said coil means during said second timer interval; and receiving means remote from said transmitting means for receiving the transmitted encoded signal; and decoding means; and comparison means electrically connected to said decoding means and including means for storage of digital data and for comparing the received decoded signal with stored data to identify the specific transmitting means whose signal has been received and compared.

Claim 5

The passive identification system of claim 1 wherein said second coil in each of said transmitting means includes circuit means including: a receiving coil for receiving a portion of the electromagnetic energy radiated by said generating means during said first time interval, electrically connected through rectifier means to storage means for storing the energy received until a predetermined signal voltage is reached, whereupon the encoding means is capable of transmitting the encoded signal at said second frequency.

Claim 6

The passive identification system of claim 2 wherein said generating means generates electromagnetic energy at a frequency of greater than 125 Khz.

Claim 7

The passive identification system of claim 3 wherein said transmitting means transmits radio frequency radiation at 125 Khz and less.

Claim 8

The passive identification system of claim 2 wherein the receiving means utilizes the same power supply as said generating means.

Claim 11

The method of claim 6 wherein the article is ambulatory and the first means provided to said ambulatory article comprises a passive tag that is placed on or worn by said ambulatory article.

Claim 12

The method of claim 7 further including the step of providing responsive means coupled to said second means for effectuating a desired action in response to identifying the ambulatory article bearing the first means.

Claim 13

The method of claim 8 wherein the ambulatory article comprises an animal, and the desired action comprises dispensing a predetermined amount of feed for the particular animal that is identified.

Claim 16

A tag or other device for use in an identification system comprising: means for receiving a burst of electromagnetic radiation through a single antenna circuit from a source remote from said tag to provide power for the other functions of said tag; means for transmitting radio frequency radiation through said same single antenna circuit at a frequency different from said burst of electromagnetic radiation, said radio frequency radiation being transmitted subsequent to the receipt of said electromagnetic radiation burst, and said radio frequency radiation being capable of being received at a point remote from said tag; and means for providing digital encoded information in said tag, said digital encoded means being electrically powered by the received electromagnetic radiation and being used to modulate said radio frequency radiation that is transmitted to a receiver external of said tag.

Claim 17

A tag or other device for use in an identification system comprising: means for receiving a burst of electromagnetic radiation through a single antenna circuit from a source remote from said tag to provide power for the other functions of said tag; means for transmitting radio frequency radiation through said same single antenna circuit at a frequency different from said burst of electromagnetic radiation, said radio frequency radiation being transmitted subsequent to the receipt of said electromagnetic radiation burst, and said radio frequency radiation being capable of being received at a point remote from said tag; and means for providing digital encoded information in said tag, said digital encoded means being electrically powered by the received electromagnetic radiation and being used to modulate said radio frequency radiation that is transmitted to a receiver external of said tag.

Claim 18

An identification system for uniquely identifying a plurality of objects comprising identifier circuit means for transmitting and receiving bursts of first and second signals, respectively, at first and second frequencies, respectively, through a single antenna tank circuit; a portable transponder unit comprising single antenna circuit means for receiving said first signal burst at said first frequency or for transmitting said second signal burst at said second frequency, start circuit means for generating a start signal in response to reception of said first signal through said antenna circuit means, encoding means for generating a pre-programmed coded signal in response to said start signal, modulation means for generating said second signal at said second frequency, and for modulating said second signal with said pre-programmed coded digital signal, and for presenting said modulated second signal to said antenna circuit means; said identifier circuit means including control means for generating said first signal and for delivering a burst of said first signal to said antenna tank circuit only at desired times and for desired durations; decoding means for generating a decoded signal from the second signal received through said antenna tank circuit, said decoded signal being relatable to said pre-programmed coded signal of said transponder unit's encoding means, and storage means coupled to said decoding means for storing and holding said decoded signal; whereby said decoded signal may be used to uniquely identify an object to which said portable transponder unit is attached when said transponder unit is pre-programmed with a unique identifying coded signal.

Claim 19

An identification system for uniquely identifying a plurality of objects comprising identifier circuit means for transmitting and receiving bursts of first and second signals, respectively, at first and second frequencies, respectively, through a single antenna tank circuit; a portable transponder unit comprising single antenna circuit means for receiving said first signal burst at said first frequency or for transmitting said second signal burst at said second frequency, start circuit means for generating a start signal in response to reception of said first signal through said antenna circuit means, encoding means for generating a pre-programmed coded signal in response to said start signal, modulation means for generating said second signal at said second frequency, and for modulating said second signal with said pre-programmed coded digital signal, and for presenting said modulated second signal to said antenna circuit means; said identifier circuit means including control means for generating said first signal and for delivering a burst of said first signal to said antenna tank circuit only at desired times and for desired durations; decoding means for generating a decoded signal from the second signal received through said antenna tank circuit, said decoded signal being relatable to said pre-programmed coded signal of said transponder unit's encoding means, and storage means coupled to said decoding means for storing and holding said decoded signal; whereby said decoded signal may be used to uniquely identify an object to which said portable transponder unit is attached when said transponder unit is pre-programmed with a unique identifying coded signal.

Claim 20

The identification system of claim 12 wherein said identifier means further comprises comparison means for electronically comparing the decoded signal against a plurality of stored signals in order to identify the specific transponder unit from which the decoded signal was derived; and response means for generating a plurality of control signals in response to the identification made by said comparison means; and undertaking a predetermined activity in response to said control signals.

Claim 21

The identification system of claim 12 wherein said portable transponder unit further comprises delay means for delaying the delivery of start signal to said encoding means for a pre-determined time, whereby the transmission of the modulated second signal back to the identifier circuit means may be delayed until after the transmission of said first signal to said transponder unit.

Claim 22

The identification system of claim 14 wherein the antenna circuit means of said portable transponder unit includes automatic tuning means for tuning the antenna circuit means to said first frequency when said first signal is being transmitted to said transponder unit, and for tuning the antenna circuit means to said second frequency when said second signal is being transmitted from said transponder unit.

Claim 23

The identification system of claim 15 wherein said first signal is an electromagnetic signal and wherein said portable transponder unit is a passive device that derives its operating power from the electromagnetic energy associated with said first signal.

Claim 24

The identification system of claim 16 wherein the start circuit means of said portable transponder unit includes means for storing the energy derived from said first signal, and means for detecting when said stored energy exceeds a specified threshold level, said start signal being generated when said threshold level is exceeded.

Claim 25

The identification system of claim 17 wherein said modulation means of said portable transponder unit includes an oscillator that generates a signal at said second frequency that is keyed on and off by said pre-programmed coded signal.