Object identification system

An object identification system comprising:

• a transceiver having a first signal detection sensitivity and including means for transmitting a write signal;
• and
• a transponder having a second signal detection sensitivity less than said first sensitivity, the transponder including
• means for receiving and detecting said write signal,
• memory device for storing an identification code of said transponder, said identification code including bits able to have a plurality of logical states, and
• means for creating an identification signal representative of said identification code such that said identification signal is modulated by the logical state of said bits;
• said transceiver further comprising means for receiving and interpreting said identification signal;
• said transponder further comprising
• a variable code generator,
• means for writing in said memory device, in response to the detection of said write signal, a variable code from said variable code generator such that said variable code constitutes at least part of said identification code, and
• modulation and amplification means for modulating a carrier with said identification code in order to create said identification signal.

An object identification system comprising:

• a transceiver having a first signal detection sensitivity and including means for transmitting a write signal;
• and
• a transponder having a second signal detection sensitivity less than said first sensitivity, the transponder including
• means for receiving and detecting said write signal,
• a memory device for storing an identification code of said transponder, said identification code including bits able to have a plurality of logical states, and
• means for creating an identification signal representative of said identification code such that said identification signal is modulated by the logical state of said bits;
• said transceiver further comprising means for receiving and interpreting said identification signal;
• said transponder further comprising
• a variable code generator, and
• means for writing in said memory device, in response to the detection of said write signal, a variable code from said variable code generator such that said variable code constitutes at least part of said identification code;
• and
• wherein said variable code generator includes a cyclically incremented and non-determinatedly stopping output counter.