Claims Analysis
Total Claims: 25
Claim 1
Independent Claim
154 words
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, 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 a part of said identification code.
Claim 2
Dependent Claim
154 words
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, 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 a part of said identification code.
Claim 3
Dependent Claim
20 words
An object identification system according to claim 1, wherein said variable code generator comprises a random or pseudo-random code generator.
Claim 4
Dependent Claim
38 words
An object identification system according to claim 1, wherein said means for creating an identification signal are adapted such that said identification signal is amplitude modulated by the logical state of the bits which constitutes said identification code.
Claim 5
Dependent Claim
172 words
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.
Claim 6
Dependent Claim
172 words
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.
Claim 7
Dependent Claim
32 words
An object identification system according to claim 4, wherein said modulation and amplification means are adapted such that amplitude variations during the transmission of said identification signal is less than 15 volts.
Claim 8
Dependent Claim
18 words
An object identification system according to claim 5, wherein the amplitude variation is between 1 and 10 volts.
Claim 9
Dependent Claim
24 words
An object identification system according to claim 5, wherein the maximum amplitude during the transmission of said identification signal is less than 15 volts.
Claim 10
Dependent Claim
35 words
An object identification system according to claim 1, wherein said means for transmitting a write signal are adapted such that said amplitude variation of the write signal during its transmission is greater than 15 volts.
Claim 11
Dependent Claim
24 words
An object identification system according to claim 8, wherein said amplitude variation of the write signal during its transmission is greater than 200 volts.
Claim 12
Dependent Claim
24 words
An object identification system according to claim 8, wherein the maximum amplitude during the transmission of said write signal is greater than 15 volts.
Claim 13
Dependent Claim
27 words
An object identification system according to claim 1, wherein said variable code generator comprises a counter whose contents vary asynchronously with the transmission of said write signal.
Claim 14
Dependent Claim
19 words
An object identification system according to claim 11, wherein the counter is not reset to zero during its initialization.
Claim 15
Dependent Claim
26 words
An object identification system according to claim 1, wherein said memory device is at least partially constituted by a non-volatile memory for storing said variable code.
Claim 16
Dependent Claim
42 words
An object identification system according to claim 1, wherein said identification code stored in said memory device includes, as well as said variable code, a code which may be determined in advance of the reception of said write signal by said transponder.
Claim 17
Dependent Claim
36 words
An object identification system according to claim 14 wherein said memory device is further constituted by a volatile memory for storing said code which may be determined in advance of the reception of said write signal.
Claim 18
Dependent Claim
27 words
An object identification system according to claim 1, wherein the variable code generator is provided with a feedback shift register for generating a pseudo random number sequence.
Claim 19
Dependent Claim
29 words
An object identification system according to claim 1, wherein the variable code generator is provided with a noise source followed by a limiter-amplifier for outputting a random bit sequence.
Claim 20
Dependent Claim
169 words
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.
Claim 21
Dependent Claim
169 words
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.
Claim 22
Dependent Claim
21 words
An object identification system according to claim 18, wherein the output counter is clocked with pulses derived from an interrogation field.
Claim 23
Dependent Claim
20 words
An object identification system according to claim 19, wherein the output counter receives a stop pulse via the interrogation field.
Claim 24
Dependent Claim
41 words
An object identification system according to claim 18, wherein the output counter is stopped by a control counter upon reaching a predetermined control counter count, the latter in turn receiving its incrementing pulses from a free running oscillator within the transponder.
Claim 25
Dependent Claim
23 words
An object identification system according to claim 21, wherein the oscillator is adapted to be switched on and off via the interrogation field.