Vehicle identification classification and communication system
First Claim
1. An interrogator transponder system for electronically interrogating and communicating with multiple closely spaced vehicles including at least one interrogating device which transmits a sequence of differing address and associated message digital codes, said codes being interleaved with a sequence of identical interrogation signals, said interrogating devices being located remotely from multiple vehicles and transponder means on the vehicles for receiving the interrogator signals decoding the message codes whose associated address code is identical to the transponder identifying code and responding to the interrogation signal at a time that is precisely synchronized with the interrogation signal after a number of interrogations have been received and means in the transponders to insure that each transponder responds to a difference sequence of interrogation signals after a plurality of interrogation signals have been received.
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Accused Products
Abstract
An interrogator-transponder system in which multiple vehicle mounted transponders which may be closely spaced in distance and moving at similar velocities are interrogated by interrogation signals that are identical for all interrogations. Digital coded data blocks consisting of an address code and a message code are transmitted on the interrogation frequency and are interleaved with the interrogation signals. Transponders respond with a coherent identification code and a message data code signal that is displaced in frequency from the interrogation signal by an amount that is identical for each transponder. The transponders decode interrogator data blocks that are associated with an address that is identical to the transponder identification code. The response signal spacings in time are difference for each transponder but are always multiples of the pulse repetition interval of the interrogation signal. Means are provided in the interrogation device to determine the velocity of each transponder, its range with respect to the interrogator, its identity and the contents of the transponder messages. Means are also provided to determine the range and velocity of transponder and nontransponder-equipped vehicles using the vehicle skin reflection of the interrogation signal.
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Citations
8 Claims
- 1. An interrogator transponder system for electronically interrogating and communicating with multiple closely spaced vehicles including at least one interrogating device which transmits a sequence of differing address and associated message digital codes, said codes being interleaved with a sequence of identical interrogation signals, said interrogating devices being located remotely from multiple vehicles and transponder means on the vehicles for receiving the interrogator signals decoding the message codes whose associated address code is identical to the transponder identifying code and responding to the interrogation signal at a time that is precisely synchronized with the interrogation signal after a number of interrogations have been received and means in the transponders to insure that each transponder responds to a difference sequence of interrogation signals after a plurality of interrogation signals have been received.
Specification