Patents by Inventor Raj Bridgelall

Raj Bridgelall has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Publication number: 20060125690
    Abstract: The location of unmodified wireless assets in a wireless communication network may be identified using time differences of arrivals of a communication sequence at different network receivers. Time-stamping devices may include correlator circuits in parallel with signal decoders to time-stamp communication sequences. Cellular wireless networks may be frequency-multiplexed to increase spatial time-stamping density. Tags may be attached to passive assets to provide location identification information to network devices. Locations of assets broadcasting standard 802.11 radio frequency structures may be identified. Noise inherent in correlating a communication sequence may be reduced by using a selected correlation function.
    Type: Application
    Filed: February 3, 2006
    Publication date: June 15, 2006
    Inventors: David Goren, Dean Kawaguchi, Raj Bridgelall, Benjamin Bekritsky, Chris Zegelin
  • Publication number: 20060107307
    Abstract: A system and method for controlling access to a wireless networking system using RFID tags is provided. The security system and method uses RFID tags to determine the location of mobile computing device. The security system and method selectively allows access to the wireless networking system based on the determined location of the mobile computing device. For example, the security system and method will permit access to the wireless networking system if the mobile computing device is determined to be in an area of permitted access. Conversely, the security system and method will deny access to the wireless networking system if the mobile computing device is determined to be not within an area of permitted access. Thus, the system and method is able to effectively control access to the wireless networking system by only permitting access to mobile devices within designated areas.
    Type: Application
    Filed: September 29, 2004
    Publication date: May 18, 2006
    Inventors: Michael Knox, Raj Bridgelall
  • Patent number: 7039027
    Abstract: A Mobile Station (MS) is able to vertically roam in either direction between two different nerworks, i.e, WWAN and WLAN. The MS is equipped with a dual mode Radio for WWAN and WLAN transmissions. The WLAN Radio is linked to a WLAN Enterprise Gateway Controller (EGC) via a first air link and the WWAN Radio is linked to a WWAN Base Transceiver Station (BTS) via a second air link. An outgoing VoIP call from the WLAN Radio to a remote party on the WWAN will transition or seamlessly switch over to a WWAN connection when the MS detects packet error rates, frequent scale back or consistent signal degradation.
    Type: Grant
    Filed: December 14, 2001
    Date of Patent: May 2, 2006
    Assignee: Symbol Technologies, Inc.
    Inventor: Raj Bridgelall
  • Patent number: 7030812
    Abstract: A system and method for synchronizing internal clocks of receiving stations of a locating system are described. A beacon transmits reference data packets at a known position. A first arrival time is compared to a second arrival time to determine a correlated arrival time data. The first arrival time is a time of reception of the reference data packets by a first receiving station, and the second arrival time is a time of reception of the reference data packets by a second receiving station. A linear polynomial fit is computed as a function of the correlated arrival time data and the first and second arrival times. Times of arrival of data packets at the first and second receiving stations is synchronized as a function of the linear polynomial fit.
    Type: Grant
    Filed: November 14, 2001
    Date of Patent: April 18, 2006
    Assignee: Symbol Technologies Inc.
    Inventors: Benjamin J. Bekritsky, David Goren, William Sakoda, Raj Bridgelall
  • Patent number: 7030761
    Abstract: A multi-resolution object location system and method for locating objects is provided. The multi-resolution system and method uses a long-range object locator together with a more precise RFID locator to efficiently and accurately determine the location of objects that include an RFID tag. The long-range object locator has a relatively longer range and can cover a relatively large area to determine the general location of the object within the large area. The RFID locator has a relatively shorter range, but is able to locate the object more precisely. The object location system uses the long-range locator to first determine the general location of the object, and then the RFID locator is used to determine a more accurate location of the object. Thus, the multi-resolution object location system is able to provide both a long range location of objects over a large area and a precise location of objects.
    Type: Grant
    Filed: March 16, 2004
    Date of Patent: April 18, 2006
    Assignee: Symbol Technologies
    Inventors: Raj Bridgelall, Mark William Duron, Martin J. Strzelczyk
  • Patent number: 7030811
    Abstract: The location of unmodified wireless assets in a wireless communication network may be identified using time differences of arrivals of a communication sequence at different network receivers. Time-stamping devices may include correlator circuits in parallel with signal decoders to time-stamp communication sequences. Cellular wireless networks may be frequency-multiplexed to increase spatial time-stamping density. Tags may be attached to passive assets to provide location identification information to network devices. Locations of assets broadcasting standard 802.11 radio frequency structures may be identified. Noise inherent in correlating a communication sequence may be reduced by using a selected correlation function.
    Type: Grant
    Filed: November 14, 2001
    Date of Patent: April 18, 2006
    Assignee: Symbol Technologies, Inc.
    Inventors: David P. Goren, Dean Kawaguchi, Raj Bridgelall, Benjamin J. Bekritsky, Chris Zegelin
  • Publication number: 20060071790
    Abstract: Methods and apparatus are provided to locate a terminal within a workspace. Radio frequency identification (RFID) tags are provided in known locations, preferably in, on or adjacent the light fixtures or other workspace infrastructure. The terminal comprises an RFID tag interrogation transceiver, processor and memory. The transceiver interrogates the tags which respond with information correlatable with their unique locations. The terminal determines its locations relative to the known locations of responding tags by, for example, varying its transmit power and/or receiver sensitivity and/or by trilateration using, for example, phase or time difference of arrival measurements on the tag response signals. Once it has determined its own location it may transmit or otherwise announce its location as desired by the user.
    Type: Application
    Filed: September 29, 2004
    Publication date: April 6, 2006
    Inventors: Mark Duron, Raj Bridgelall
  • Publication number: 20060066441
    Abstract: A portable/handheld device is provided having a processing module configured to selectively operate a reading mode selected from a far-field mode and a near-field mode, and a directional antenna array coupled to the processing module. The directional antenna array includes a first antenna element configured to radiate electromagnetic (EM) radiation in a far-field, and a second antenna element coupled to the first antenna element. The second antenna element is configured to radiate EM radiation in a near-field. The second antenna element includes an antenna transducer configured to selectively cancel far-field EM radiation from the first antenna element. A method of reading inductively coupled radio frequency identification (RFID) tags is also provided having the steps of scanning at least one frequency band to detect a RFID tag, and selectively radiating one of a near-field electromagnetic (EM) field and a far-field EM field based on the detected RFID tag.
    Type: Application
    Filed: September 30, 2004
    Publication date: March 30, 2006
    Inventors: Richard Knadle, Hal Charych, Mark Duron, Raj Bridgelall
  • Publication number: 20060044112
    Abstract: A wearable RFID system of wearing on the body of a user is disclosed. The wearable RFID system comprises an RFID reader, a network controller coupled to the RFID reader and a network transceiver coupled to the network controller. The wearable RFID reader reads data stored on RFID tags, such as a product code. This data can then be sent to the network controller and then to the network transceiver. The network transceiver can send the information to an external network for processing or storage.
    Type: Application
    Filed: August 31, 2004
    Publication date: March 2, 2006
    Inventor: Raj Bridgelall
  • Publication number: 20060044147
    Abstract: An object location system and method is provided for locating objects. The system includes an RFID reader, an angle calculator, and a distance calculator to determine which of a plurality of zones an object is located in or passing through. An RFID tag is affixed with the object that is to be located. The RFID reader transmits signals to the RFID tag and receives backscatter-modulated signals from the RFID tag at one or more RFID antennas. From those received signals, the angle calculator determines an angle of position of the RFID tag relative to the RFID antenna. From the angle of position the zone in which the object is located is determined.
    Type: Application
    Filed: August 31, 2004
    Publication date: March 2, 2006
    Inventors: Michael Knox, Raj Bridgelall, Mark Duron, Richard Knadle, James Bender
  • Patent number: 7005968
    Abstract: A locating and tracking system is provided in which the assets desired to be located and tracked are associated with either radio frequency (RF) tags or radio frequency identification and radio frequency data communication (RFID/RFDC) devices. Depending on which device is attached to the asset, the other device is located at known locations. The RFID/RFDC devices interrogate and receive signals from the RF tags. The received information is sent to a host computer. With the location of either the RF tags or RFID/RFDC devices known, the assets may be located and tracked. An improved RF tag antenna design is also provided by using a switching mechanism connected to at least two antennas.
    Type: Grant
    Filed: June 7, 2000
    Date of Patent: February 28, 2006
    Assignee: Symbol Technologies, Inc.
    Inventor: Raj Bridgelall
  • Publication number: 20060033609
    Abstract: A locating and tracking system is provided in which the assets are desired to be located and tracked are associated with either radio frequency (RF) tags or radio frequency identification and radio frequency data communication (RFID/RFDC) devices. Depending on which device is attached to the asset, the other device is located at known locations. The RFID/RFDC devices interrogate and receive signals from the RF tags. The received information is sent to the host computer. With the location of either the RF tags or the RFID/RFDC devices known, the assets may be located and tracked. An improved RF tag antenna design is also provided by using a switching mechanism connected to at least two antennas.
    Type: Application
    Filed: October 5, 2005
    Publication date: February 16, 2006
    Inventor: Raj Bridgelall
  • Patent number: 6998983
    Abstract: Described are RF tracking system and method. The RF system may include a shell for holding a plurality of containers which store a material that interferes with RF communications. The shell includes a bottom container supporting surface and a plurality of leg extensions attached thereto; the shell extends away from the bottom surface. The tracking system also includes at least one RF tag attached to a first one of the leg extensions. The tag has a memory arrangement storing data relating to at least one of an identity of the shell, an identity of the containers held in the shell and a material stored in the containers. Furthermore, the tracking system includes at least one RF scanner communicating with the tag to collect the data and a computing arrangement which includes a database and communicating with the scanner to update the database as a function of the collected data.
    Type: Grant
    Filed: November 19, 2003
    Date of Patent: February 14, 2006
    Assignee: Symbol Technologies, Inc.
    Inventors: Hal Charych, Raj Bridgelall, Avi Nudelman
  • Publication number: 20060022802
    Abstract: A wireless communication system implements various RFID-based methods for wireless communication devices and wireless network infrastructures. The communication system includes an RFID tag and a wireless communication device. The RFID tag is configured to receive an RFID interrogation signal and, upon receipt thereof, to supply one or more transition signals. The wireless communication device is configured to operate in a plurality of operational states, is coupled to receive the transition signals, and is configured, upon receipt thereof, to transition from at least a first operational state to a second operational state.
    Type: Application
    Filed: July 30, 2004
    Publication date: February 2, 2006
    Inventor: Raj Bridgelall
  • Publication number: 20050285742
    Abstract: Methods and apparatus are provided for locating one among many items equipped with RFID tags. The apparatus comprises a portable system interrogating the RFID tags and receiving responses therefrom that depend at least on their bearing angle. A comparator selects responses from the one item and ignores others. An annunciator indicates the presence of the one item in the interrogator field of view and, desirably but not essentially, its relative proximity. A directional antenna whose beam pattern is limited in azimuth and/or elevation provides bearing angle information. Its field of view becomes progressively smaller as the antenna approaches the one item so that a user can substantially pinpoint its location without needing any of the usual RFID infrastructure. Tag response hit rate and/or signal strength provides range related information to the interrogator. Optionally, the presence of each new tag is announced until all new tags have been identified.
    Type: Application
    Filed: June 29, 2004
    Publication date: December 29, 2005
    Inventors: Hal Charych, Raj Bridgelall, Sumita Malik, Michael O'Haire
  • Publication number: 20050206555
    Abstract: A multi-resolution object location system and method for locating objects is provided. The multi-resolution system and method uses a long-range object locator together with a more precise RFID locator to efficiently and accurately determine the location of objects that include an RFID tag. The long-range object locator has a relatively longer range and can cover a relatively large area to determine the general location of the object within the large area. The RFID locator has a relatively shorter range, but is able to locate the object more precisely. The object location system uses the long-range locator to first determine the general location of the object, and then the RFID locator is used to determine a more accurate location of the object. Thus, the multi-resolution object location system is able to provide both a long range location of objects over a large area and a precise location of objects.
    Type: Application
    Filed: March 16, 2004
    Publication date: September 22, 2005
    Inventors: Raj Bridgelall, Mark Duron, Martin Strzelczyk
  • Publication number: 20050201301
    Abstract: Methods and apparatus are provided for automatically and autonomously forming a wireless personal area network (WPAN) from an array of intercommunicating personal area network (PAN) devices. The devices comprise first communicators associated with primary functions of the devices and second communicators coupled to the first communicators for determining a subset of the devices meeting predetermined association criteria, from which subset the first communicators form the WPAN. In a preferred embodiment, the second communicators include range measuring transceivers and processors coupled to the transceivers that cooperate to determine range and relative motion of elements within communication range of the first communicators for comparison to range and relative motion association criteria stored in one or more of the devices. Memory is desirably included for storing the association criteria.
    Type: Application
    Filed: June 30, 2004
    Publication date: September 15, 2005
    Inventor: Raj Bridgelall
  • Publication number: 20050200457
    Abstract: An apparatus is provided for an inventory transport device having a fixed section and a movable section. The apparatus comprises a RFID reader device mounted on the movable section; and a RFID power device mounted on the fixed section. The RFID power device provides power to the RFID reader device without physical contact.
    Type: Application
    Filed: March 11, 2004
    Publication date: September 15, 2005
    Inventors: Raj Bridgelall, Michael Knox, Hal Charych, Mark Duron, Richard Knadle
  • Publication number: 20050200456
    Abstract: A system for communicating data through a network is disclosed. The system includes at least one access point and at least one mobile unit. The access point includes an access point processor, a wireless transceiver and an RFID transceiver. The wireless transceiver is coupled to the access point processor and the wireless transceiver is configured to receive and transmit data to a wireless device in the wireless local area network. The RFID transceiver is coupled to the access point processor and the RFID transceiver is configured to receive data from at least one mobile unit in the wireless local area network when the wireless transceiver is unavailable. The mobile unit includes a mobile unit processor, a mobile unit wireless transceiver and a mobile unit RFID transceiver. The mobile unit wireless transceiver is coupled to the mobile unit processor and the mobile unit wireless transceiver is configured to receive and transmit data to the access point.
    Type: Application
    Filed: March 11, 2004
    Publication date: September 15, 2005
    Inventor: Raj Bridgelall
  • Publication number: 20050201300
    Abstract: Methods and apparatus are provided for forming a wireless personal area network (WPAN) from an array of intercommunicating personal area network (PAN) devices. The system comprises a location determinator configured to determine a location for each of the PAN devices, a comparator coupled to the determinator for comparing the location of each of the PAN devices with WPAN association criteria to choose a subset meeting the WPAN criteria at least in part, and a communication link coupled to the comparator to transmit identification data of the subset to some or all of the subset of PAN devices. When received, the information causes the subset to form the WPAN, which then intercommunicate substantially ignoring the non-WPAN devices. In a preferred embodiment, the comparator selects the WPAN from those of the plurality of PAN devices that are within a predetermined distance of each other and/or move as a group.
    Type: Application
    Filed: March 11, 2004
    Publication date: September 15, 2005
    Inventor: Raj Bridgelall