公开(公告)号：JPH10206538A

公开(公告)日：1998-08-07

申请号：JP1003198

申请日：1998-01-05

Applicant: LUCENT TECHNOLOGIES INC

Inventor： ALEX PIDWARBEKKY ,  R ANTHONY SHOVER

IPC: G01S13/524 ,  G01S3/48 ,  G01S5/04 ,  G01S13/536 ,  G01S13/74 ,  G01S13/87 ,  G01S13/90 ,  G06K7/00 ,  H04B1/40

Abstract: PROBLEM TO BE SOLVED: To provide FRID(radio frequency discriminator) in which necessary tag data are quickly transmitted even in the case where a plurality of tags exist in a reading area, which has up-link of relatively high speed and in which synchronization is quickly taken. SOLUTION: A radio transmission system generates a first modulation signal modulating a first information signal on a radio carrier signal, and has interrogators 103, 104 for transmitting it. The first information signal instructs by which of a plurality of response modes receiving tags 105-107 responds. At least one tag of the system receives the first modulation signal, and decodes to obtained the first information signal. A backscatterring modulator modulates the reflection of the first modulation signal by means of a second information signal. The contents, the data rate or the modulation of the second information signal are determined by the first information signal to form a second reflection modulation signal. The interrogators 103, 104 receive the second modulation signal, and decode to obtain the second information signal.

公开(公告)号：JP2000049656A

公开(公告)日：2000-02-18

申请号：JP7268099

申请日：1999-03-17

Applicant: LUCENT TECHNOLOGIES INC

Inventor： MACLELLAN JOHN AUSTIN ,  R ANTHONY SHOVER

IPC: H04B7/26 ,  G06K7/00 ,  H04B1/59 ,  H04B5/02 ,  H04J1/00 ,  H04L5/16 ,  H04L12/28

Abstract: PROBLEM TO BE SOLVED: To provide a short-distance radio data communication from a central control point (interrogator) to many inexpensive end points (tag). SOLUTION: A tag 105 uses a modulation back-scatter method for a communication from the tag 105 to an interrogator 103. A new down-link protocol is used for data transmission from the interrogator 103 to the tag 105 and a new up-link protocol is used for data transmission from the tag 105 to the interrogator 103. Either protocol resends messages which are neither confirmed nor answered at random by using back-off/retry algorithm. The transmission capacity from the tag 105 to the interrogator 103 is improved more by using up-link subcarrier frequency-division multiplexing. In concrete, the tag 105 includes a sensor for temperature, smoke, or living body information and sends its output to the interrogator 103 with an up-link information signal.

公开(公告)号：JPH10209912A

公开(公告)日：1998-08-07

申请号：JP35721397

申请日：1997-12-25

Applicant: LUCENT TECHNOLOGIES INC

Inventor： YOSUN UU ,  R ANTHONY SHOVER

IPC: H04L27/22 ,  H03D1/22 ,  H03D3/00 ,  H04B1/59 ,  H04B5/00

Abstract: PROBLEM TO BE SOLVED: To ensure the appropriateness of an RFID (radio frequency identification) system by using a phase shifter which causes a 90-degree phase shift out of one of modulator output signals in regard to the 2nd frequency and an adder which adds another modulator output signal to a phase-shifted output signal in terms of vector. SOLUTION: An in-phase/quadrature phase coupler of an RFID system utilizes a modulation rear dispersion technique with which a modulated subcarrier undergoes the rear dispersion modulation for a CW carrier signal. Then the phase coupler connects together the quadrature and in-phase outputs of an quadrature demodulator in terms of non-destruction. The I and Q outputs of the quadrature demodulator are orthogonal to each other in relation to the carrier frequency. The I output is applied to the input side of a phase shifter 200 and causes a 90-degree phase shift to the I mixer output in relation to the subcarrier frequency. The output of the shifter 200 is connected to the input side of an adder 202. The output of the adder 202 is equal to the vector sum of the Q output and the phase-shifted I output.

公开(公告)号：JPH10209914A

公开(公告)日：1998-08-07

申请号：JP1003098

申请日：1998-01-05

Applicant: LUCENT TECHNOLOGIES INC

Inventor： MACLELLAN JOHN AUSTIN ,  R ANTHONY SHOVER ,  VANNUCCI GIOVANNI ,  WRIGHT GREGORY ALAN

IPC: H04B5/02 ,  G06K7/00 ,  H04B1/59 ,  H04L27/20 ,  H04L27/233

Abstract: PROBLEM TO BE SOLVED: To eliminate the influence of noises, etc., of an oscillator by using an orthogonal phase shift key and also to extend this key to a higher dimension in an MBS(modulation back scatter) system. SOLUTION: An application processor 101 communicates with the question units 103 and 104 via a LAN 102, and the units 103 and 104 communicate with one or plural ones of tags 105 to 107. The unit 103 receives and fetches an information signal from the processor 101 and sends a message (down link message) and then the continuous wave radio signals to the tags. The tags modulate the received continuous wave radio signals via an MBS system. An antenna is switched to a reflector state from an absorber state for radiation of the radio frequency by a modulation signal. Thus, the communication to the question units from the tags via the MBS system is made possible.