Wayne D Shanks

US Patent:

6734797, May 11, 2004

Filed:

Feb 12, 2002

Appl. No.:

10/072985

Inventors:

Wayne E. Shanks - Baltimore MD
William R. Bandy - Gambrills MD
Michael R. Arneson - Westminister MD
Kevin J. Powell - Annapolis MD

Assignee:

Matrics, Inc. - Columbia MD

International Classification:

G08B 1314

US Classification:

3405724, 3405721

Abstract:

An identification (ID) tag includes a substrate having an input capable of receiving a high frequency signal. For instance, the high frequency signal can be a radio frequency (RF) signal that is generated as part of a radio frequency (RF) ID system. A first charge pump is coupled to the input and is configured to convert the high frequency signal to a substantially direct current (DC) voltage. A data recovery circuit is coupled to the input and is capable of recovering data from the high frequency signal. A back scatter switch is coupled to the input and is capable of modifying an impedance of the input, responsive to a control signal. A state machine is disposed on the substrate and is responsive to the data recovered by the second charge pump, where the state machine is capable of generating the control signal for the back scatter switch in response to the data. The DC voltage from the first charge pump is capable of providing a voltage supply for at least one of the data recovery circuit, the back scatter switch, and the state machine. The data recovery circuit includes a second charge pump that is capable of operating on the high frequency signal simultaneously with the first charge pump.

US Patent:

6784813, Aug 31, 2004

Filed:

Feb 12, 2002

Appl. No.:

10/072870

Inventors:

Wayne E. Shanks - Baltimore MD
William R. Bandy - Gambrills MD
Kevin J. Powell - Annapolis MD
Michael R. Arneson - Westminister MD

Assignee:

Matrics, Inc. - Columbia MD

International Classification:

H03M 508

US Classification:

341 53, 3405721, 235435

Abstract:

A method, system, and apparatus for remotely calibrating data symbols received by a radio frequency identification (RFID) tag population are described. Tags are interrogated by a reader, which may be located in a network of readers. The reader transmits data symbols to the tags. Tags respond to the interrogations with symbols that each represent one or more bits of data. To calibrate the tags, the reader transmits a plurality of pulses of different lengths to the tag population. The tags receive the plurality of pulses. A characteristic of each pulse, such as a pulse length, is stored by the tags. The stored pulse lengths are used to define different data symbols that are subsequently received by the tags from the reader.

US Patent:

6956509, Oct 18, 2005

Filed:

Aug 26, 2004

Appl. No.:

10/926269

Inventors:

Wayne E. Shanks - Baltimore MD, US
William R. Bandy - Gambrills MD, US
Kevin J. Powell - Annapolis MD, US
Michael R. Arneson - Westminister MD, US

Assignee:

Symbol Technologies, Inc. - Holtsville NY

International Classification:

H03M005/08
G08B013/14
H04Q005/22

US Classification:

341 53, 3405721, 340 102

Abstract:

A method, system, and apparatus for remotely calibrating data symbols received by a radio frequency identification (RFID) tag population are described. Tags are interrogated by a reader, which may be located in a network of readers. The reader transmits data symbols to the tags. Tags respond to the interrogations with symbols that each represent one or more bits of data. To calibrate the tags, the reader transmits a plurality of pulses of different lengths to the tag population. The tags receive the plurality of pulses. A characteristic of each pulse, such as a pulse length, is stored by the tags. The stored pulse lengths are used to define different data symbols that are subsequently received by the tags from the reader.

US Patent:

6989750, Jan 24, 2006

Filed:

Feb 12, 2002

Appl. No.:

10/072984

Inventors:

Wayne E. Shanks - Baltimore MD, US
William R. Bandy - Gambrills MD, US
Michael R. Arneson - Westminister MD, US
Kevin J. Powell - Annapolis MD, US

Assignee:

Symbol Technologies, Inc. - Holtsville NY

International Classification:

G08B 13/14

US Classification:

3405724, 3405721

Abstract:

A radio frequency identification (RFID) architecture is described. RFID tags are interrogated by a reader, which may be located in a network of readers. The reader transmits symbols to the tags. Tags respond to the interrogations with symbols that each represent one or more bits of data. An RFID tag includes an antenna pad, a receiver, a state machine, and a modulator. The receiver is coupled to the antenna pad. The receiver receives a symbol from the antenna pad and outputs a received signal. The state machine is configured to determine a response symbol from the received signal and an operating state of the tag. The modulator is coupled to the antenna pad. The modulator is configured to backscatter modulate the received symbol with the response symbol. The modulator is configured to output the backscatter modulated symbol to the antenna pad.

US Patent:

7057511, Jun 6, 2006

Filed:

Feb 12, 2002

Appl. No.:

10/073000

Inventors:

Wayne E. Shanks - Baltimore MD, US
William R. Bandy - Gambrills MD, US
Kevin J. Powell - Annapolis MD, US
Michael R. Arneson - Westminster MD, US

Assignee:

Symbol Technologies, Inc. - Holtsville NY

International Classification:

G08B 13/14

US Classification:

3405721, 3405728

Abstract:

A method, system, and apparatus for communicating with a radio frequency identification (RFID) tag population that includes one or more tags are described. The tags are interrogated by a reader which may be located in a network of readers. The reader interrogates the tags by transmitting data symbols to the tags. Tags respond to the reader with backscatter symbols. Bit patterns, such as identification numbers stored in the tags, are collected from the plurality of tags without collisions. Collisions are avoided because the backscatter symbols transmitted by the tags use different characteristics to represent different data bits. For example, a first backscatter symbol frequency is used by the tag to represent a “0” bit, and a second backscatter symbol frequency is used by the tag to represent a “1” bit.

US Patent:

7068148, Jun 27, 2006

Filed:

Oct 20, 2003

Appl. No.:

10/687690

Inventors:

Wayne Shanks - Baltimore MD, US
Jens Arnold - Perry Hall MD, US

Assignee:

Symbol Technologies, Inc. - Holtsville NY

International Classification:

H04Q 5/22

US Classification:

340 101, 340 102

Abstract:

A method for reading and tracking radio frequency identification (RFID) tags in the presence of a noisy air channel is provided. In accordance with the method, a binary tree data structure is used to characterize a plurality of RFID tags, each of which is associated with a unique identification (ID) number. During communication between a tag reader and one or more RFID tags, the tag reader traverses the binary tree, eliminating tags from communication until one tag with a unique ID number is isolated and verified. As the binary tree is traversed, counters associated with each node in the tree are incremented based on tag matches, such that, over time, counters associated with nodes in tag-populated branches will tend to have a high value and counters associated with nodes in unpopulated tree branches will tend to have low values. Where the read process is subject to noise and the tag reader is forced make a decision at a branching node, the tag reader makes a branch prediction based on the current value of the node counters associated with each of the possible alternative branches.

US Patent:

7068173, Jun 27, 2006

Filed:

May 7, 2004

Appl. No.:

10/840790

Inventors:

Wayne E. Shanks - Gambrills MD, US
William R. Bandy - Gambrills MD, US
Michael R. Arneson - Westminster MD, US
Kevin J. Powell - Annapolis MD, US

Assignee:

Symbol Technologies, Inc. - Holtsville NY

International Classification:

G08B 13/14

US Classification:

3405724, 3405721

Abstract:

An identification (ID) tag includes a substrate having an input capable of receiving a high frequency signal. For instance, the high frequency signal can be a radio frequency (RF) signal that is generated as part of a radio frequency (RF) ID system. A first charge pump is coupled to the input and is configured to convert the high frequency signal to a substantially direct current (DC) voltage. A data recovery circuit is coupled to the input and is capable of recovering data from the high frequency signal. A back scatter switch is coupled to the input and is capable of modifying an impedance of the input, responsive to a control signal. A state machine is disposed on the substrate and is responsive to the data recovered by the second charge pump, where the state machine is capable of generating the control signal for the back scatter switch in response to the data. The DC voltage from the first charge pump is capable of providing a voltage supply for at least one of the data recovery circuit, the back scatter switch, and the state machine. The data recovery circuit includes a second charge pump that is capable of operating on the high frequency signal simultaneously with the first charge pump.

US Patent:

7075436, Jul 11, 2006

Filed:

Feb 12, 2002

Appl. No.:

10/072885

Inventors:

Wayne E Shanks - Baltimore MD, US
Kevin J Powell - Annapolis MD, US
William R Bandy - Gambrills MD, US
Michael R Arneson - Westminister MD, US

Assignee:

Symbol Technologies, Inc. - Holtsville NY

International Classification:

H04Q 5/22
G08B 13/14
G08B 5/22
H01H 67/00

US Classification:

3405721, 340 103, 340 1031, 340 1032, 340 1033, 340 104, 3405723, 34082502, 34082549

Abstract:

A method, system, and apparatus for interrogating a radio frequency identification (RFID) tag population are described. Tags are interrogated by a reader. The reader and tags engage in communication according to binary traversal algorithms, where single bit data symbols are exchanged between the reader and tags. Furthermore, a reader implicitly controls the operating state of every tag in the tag population by transmitting a single data symbol. Bit patterns may be collected from the tags by the reader, using a variety of interrogation techniques. In a general interrogation, the reader exchanges symbols with the tag population to interrogate the entire tag population. In a specific interrogation, a reader exchanges symbols with the tag population to target a particular tag identification number. Tags may also be placed in a superposition state by the reader, where they respond whenever a received data symbol matches the next bit of their identification number.