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公开(公告)号：CA2267437A1
公开(公告)日：2000-01-17
申请号：CA2267437
申请日：1999-03-30
Applicant: LUCENT TECHNOLOGIES INC
Inventor： SHOBER R ANTHONY , MACLELLAN JOHN AUSTIN
Abstract: A system provides short range wireless data communication from a central control point (e.g., interrogator) to inexpensive endpoints (e.g., tags). The endpoints utilize the technology of modulated backscatter for transmission from the tags to the interrogator. The system uses a new downlink protocol for data transmission from the interrogator to the tags and a new uplink protocol for data transmission from the tags to the interrogator. Both protocols use a backoff/retry algorithm to randomly retransmit any non-acknowledged messages. System capacity from the tags to the interrogator is further enhanced by the use of uplink subcarrier frequency division multiplexing.
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公开(公告)号：CA2219268A1
公开(公告)日：1998-06-30
申请号：CA2219268
申请日：1997-10-23
Applicant: LUCENT TECHNOLOGIES INC
Inventor： WRIGHT GREGORY ALAN , MACLELLAN JOHN AUSTIN , SHOBER R ANTHONY
Abstract: In accordance with the present invention, the communication system comprises an Interrogator and one or more Tags. The Interrogator generates a modulated carrier signal by modulated a first information signal onto a radio si gnal. The Interrogator transmits a downlink signal which comprises the modulated carri er signal and the radio signal. A Tag receives and processes the downlink signal. Specifically, the Tag demodulates the first information signal from the modulate d carrier signal and generates a second information signal typically based on the contents of the first information signal. The second information signal is used to modulate a subcarrier signal, thereby generating a modulated subcarrier signal. A Backscatter Modulator using this modulated subcarrier signal modulates the reflection of the radio signal, wherein the reflected signal is an uplink signal . The Interrogator receives and demodulates the uplink signal using homodyne detection to obtain the modulated subcarrier signal, which is then demodulated using a subcar rier demodulator to obtain the second information signal. In one embodiment, frequenc y of the subcarrier signal is an integer multiple of the second information signal symbol rate and is up to half the sampling rate of the subcarrier demodulator.
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公开(公告)号：CA2267437C
公开(公告)日：2002-10-01
申请号：CA2267437
申请日：1999-03-30
Applicant: LUCENT TECHNOLOGIES INC
Inventor： SHOBER R ANTHONY , MACLELLAN JOHN AUSTIN
Abstract: A system provides short range wireless data communication from a central control point (e.g., interrogator) to inexpensive endpoints (e.g., tags). The endpoints utilize the technology of modulated backscatter for transmission from the tags to the interrogator. The system uses a new downlink protocol for data transmission from the interrogator to the tags and a new uplink protocol for data transmission from the tags to the interrogator. Both protocols use a backoff/retry algorithm t o randomly retransmit any non-acknowledged messages. System capacity from the tags to t he interrogator is further enhanced by the use of uplink subcarrier frequency division multiplexing.
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公开(公告)号：CA2248508C
公开(公告)日：2002-08-13
申请号：CA2248508
申请日：1998-09-30
Applicant: LUCENT TECHNOLOGIES INC
Inventor： MACLELLAN JOHN AUSTIN , SHOBER R ANTHONY , WRIGHT GREGORY ALAN
Abstract: The present invention involves an adaptive digital radio communications arch itecture which can be reconfigured by reprogramming at least one programmable device, and thus more efficiently use the available bandwidth of a time-varying RF channel and/or to provide a flexibl e and adaptive digital communications system. In certain embodiments, the programmable device uses a Programmable Logic Device (PLD) to perform the digital communications processing functions of t he transmitter or the receiver of a radio communications system. In this context, PLD is a general term rep resenting a family of programmable logic devices; examples of this family are a Programmable Array Logic (PAL), a Complex PLD (CPLD), and a Field Programmable Gate Array (FPGA). The architecture is reconfigurable in the sense that any or all of the digital communications processing algorithms ca n be modified by reprogramming the PLD. The architecture of the digital communications system can be characterized by the following parameters; the channel symbol rate, the occupied bandwidth, t he modulation technique, and the multiple access technique. A reconfiguration is a modification of the ar chitecture of the digital communications system, and can occur by reprogramming the PLD through extern al control, for example in the event a radio communications base station wishes to change the radio architecture being used for a particular piece of radio spectrum. A reconfiguration can also occur, for ex ample, by dynamically reprogramming the digital communications system depending upon time-varying radio channel conditions, such as the effect of the number of channel users, the offered load, quality of service measurements, or the characteristics of the desired application(s), including voice, data, video and/or tracking. Methods to measure the time varying radio channel conditions are disclosed, and further how those measurements can impact a reconfiguration. This invention discloses how the architecture for the digital communications system can be dynamically reprogrammed based upon current channel conditions and/or through external control.
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Patent Agency Ranking
公开(公告)号：CA2219270C
公开(公告)日：2001-07-31
申请号：CA2219270
申请日：1997-10-23
Applicant: LUCENT TECHNOLOGIES INC
Inventor： MACLELLAN JOHN AUSTIN , VANNUCCI GIOVANNI
Abstract: The present invention enables a Tag and Interrogator to exchange proprietary information using Modulated BackScatter (MBS) technology. This invention discloses a method for encrypting the RFID user's PIN and thereby making the interception and the subsequent illegal use of RFID accounts at l east as difficult as a present day ATM cards. For example, the encryption method can be based upon the US Digital Encryption Standard (DES), either first or third l evel. The Tag's personal encryption key is only known by the financial database an d the RFID Tag. This method can be applied to any type of financial, debt, identif ication, or credit card.
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公开(公告)号：DE69702493D1
公开(公告)日：2000-08-17
申请号：DE69702493
申请日：1997-12-16
Applicant: LUCENT TECHNOLOGIES INC
Inventor： MACLELLAN JOHN AUSTIN , VANNUCCI GIOVANNI
Abstract: The present invention enables a Tag and Interrogator to exchange proprietary information using Modulated BackScatter (MBS) technology. This invention discloses a method for encrypting the RFID user's PIN and thereby making the interception and the subsequent illegal use of RFID accounts at least as difficult as a present day ATM cards. For example, the encryption method can be based upon the US Digital Encryption Standard (DES), either first or third level. The Tag's personal encryption key is only known by the financial database and the RFID Tag. This method can be applied to any type of financial, debt, identification, or credit card.
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公开(公告)号：CA2248508A1
公开(公告)日：1999-05-07
申请号：CA2248508
申请日：1998-09-30
Applicant: LUCENT TECHNOLOGIES INC
Inventor： MACLELLAN JOHN AUSTIN , SHOBER R ANTHONY , WRIGHT GREGORY ALAN
Abstract: The present invention involves an adaptive digital radio communications architec ture which can be reconfigured by reprogramming at least one programmable device, and thus more efficiently use the available bandwidth of a time-varying RF channel and/or to provide a flexible an d adaptive digital communications system. In certain embodiments, the programmable device uses a Pr ogrammable Logic Device (PLD) to perform the digital communications processing functions of the t ransmitter or the receiver of a radio communications system. In this context, PLD is a general term represe nting a family of programmable logic devices; examples of this family are a Programmable Array Log ic (PAL), a Complex PLD (CPLD), and a Field Programmable Gate Array (FPGA). The architecture is reco nfigurable in the sense that any or all of the digital communications processing algorithms can be modified by reprogramming the PLD. The architecture of the digital communications system can be characterized by the following parameters; the channel symbol rate, the occupied bandwidth, the m odulation technique, and the multiple access technique. A reconfiguration is a modification of the archit ecture of the digital communications system, and can occur by reprogramming the PLD through external c ontrol, for example in the event a radio communications base station wishes to change the radio arch itecture being used for a particular piece of radio spectrum. A reconfiguration can also occur, for exampl e, by dynamically reprogramming the digital communications system depending upon time-varying radi o channel conditions, such as the effect of the number of channel users, the offered load, quality of service measurements, or the characteristics of the desired application(s), including voice, data, video and/ or tracking. Methods to measure the time varying radio channel conditions are disclosed, and further how those measurements can impact a reconfiguration. This invention discloses how the architecture for the digital communications system can be dynamically reprogrammed based upon current channel conditions and /or through external control.
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公开(公告)号：CA2219270A1
公开(公告)日：1998-06-30
申请号：CA2219270
申请日：1997-10-23
Applicant: LUCENT TECHNOLOGIES INC
Inventor： VANNUCCI GIOVANNI , MACLELLAN JOHN AUSTIN
Abstract: The present invention enables a Tag and Interrogator to exchange proprietary information using Modulated BackScatter (MBS) technology. This invention discloses a method for encrypting the RFID user's PIN and thereby making the interception and the subsequent illegal use of RFID accounts at least as difficult as a present day ATM cards. For example, the encryption method can be based upon the US Digital Encryption Standard (DES), either first or third level . The Tag's personal encryption key is only known by the financial database and th e RFID Tag. This method can be applied to any type of financial, debt, identificat ion, or credit card.
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公开(公告)号：CA2219266A1
公开(公告)日：1998-06-30
申请号：CA2219266
申请日：1997-10-23
Applicant: LUCENT TECHNOLOGIES INC
Inventor： MACLELLAN JOHN AUSTIN , WRIGHT GREGORY ALAN , VANNUCCI GIOVANNI , SHOBER R ANTHONY
Abstract: In accordance with the present invention, a duplex radio communication system comprises an Interrogator which generates a radio signal to at least one remote Tag. The remote Tag receives the radio signal. The Tag then generates a subcarrier signal, and using Quadrature Phase Shift Keying (QPSK), modulates an information signal onto the subcarrier. A Backscatter Modulator, us ing this modulated subcarrier, modulates the reflection of the radio signal, the ref lected signal being a reflected modulated signal. The Interrogator receives and demodul ates the reflected modulated signal to obtain the information signal. In one embodime nt, demodulation utilizes a homodyne detector. In another embodiment, the Interrogat or modulates an information signal onto the radio signal, transmits that modulated radio signal to the Tag, and the Tag demodulates that modulated radio signal to recove r the information signal. In another embodiment, higher order phase modulations are us ed to modulate an information signal onto the subcarrier.
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