Patents by Inventor Philip L. Stephenson
Philip L. Stephenson 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).
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Patent number: 7190683Abstract: A communications system employs the use of both synchronous CDMA and FDMA to provide a variable bandwidth waveform with multiple bonded transmitters and receivers that are agile in both frequency and PN code to permit a variable bandwidth and variable rate multiple access system. In a first aspect the teachings provide the use of both CDMA and FDMA together to enable an improved concentration efficiency by making a larger pool of bandwidth available to each user. In a second aspect these teachings enable channel bonding across both code space and frequency space, thus making the system capable of operating within a variable (not necessarily contiguous) bandwidth and at a finely variable rate.Type: GrantFiled: April 9, 2001Date of Patent: March 13, 2007Assignee: L-3 Communications CorporationInventors: Thomas R. Giallorenzi, Eric K. Hall, Richard B. Ertel, Philip L. Stephenson, Dan M. Griffin, Lee A. Butterfield
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Patent number: 7054286Abstract: This invention provides a highly flexible multiplexing scheme for Direct Sequence CDMA systems enabling the CDMA system to flexibly allocate CDMA channel resources between packet-switched broadcast channels and fast-circuit-switched dedicated channels in order to optimize system throughput. A method and system are provided for operating a communication system. The method has steps of: flexibly allocating CDMA channel resources between packet-switched broadcast channels and fast-circuit-switched dedicated channels in order to optimize system throughput, and employing a side channel as required to send all or a part of a total amount of data, depending on the total amount of the data. A bandwidth allocation scheme allocates a set of CDMA channels for burst packet-switched channels, and data is time division multiplexed over the set of burst CDMA channels providing a wide bandwidth data pipe for packet-switched data.Type: GrantFiled: April 9, 2001Date of Patent: May 30, 2006Assignee: L-3 Communications CorporationInventors: Richard B. Ertel, Eric K. Hall, Thomas R. Giallorenzi, Philip L. Stephenson, Johnny M. Harris, Edward P. Newren
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Patent number: 6999446Abstract: A method is disclosed for operating a wireless communications system, such as a DS-CDMA communications system, by transmitting a waveform that includes a plurality of repeating frames each having x header training base symbols in a header training symbol field (TH) and y tail training base symbols in a tail training symbol field (TT). The frame is received and functions as one of a plurality of different types of frames depending on the content of at least TT. In the preferred embodiment the frame functions as one of a normal traffic frame, a termination frame, or a legacy frame providing backwards compatibility with another waveform. A given one of the frames includes four equal-size data fields separated by three equal-sized control fields, the header training symbol field (TH) and the tail training symbol field (TT).Type: GrantFiled: October 26, 2001Date of Patent: February 14, 2006Assignee: L-3 Communications CorporationInventors: Eric K. Hall, Thomas R. Giallorenzi, Richard B. Ertel, Lee A. Butterfield, Dan M. Griffin, Philip L. Stephenson
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Publication number: 20020126650Abstract: A method is disclosed for operating a wireless communications system, such as a DS-CDMA communications system, by transmitting a waveform that includes a plurality of repeating frames each having x header training base symbols in a header training symbol field (TH) and y tail training base symbols in a tail training symbol field (TT). The frame is received and functions as one of a plurality of different types of frames depending on the content of at least TT. In the preferred embodiment the frame functions as one of a normal traffic frame, a termination frame, or a legacy frame providing backwards compatibility with another waveform. A given one of the frames includes four equal-size data fields separated by three equal-sized control fields, the header training symbol field (TH) and the tail training symbol field (TT).Type: ApplicationFiled: October 26, 2001Publication date: September 12, 2002Inventors: Eric K. Hall, Thomas R. Giallorenzi, Richard B. Ertel, Lee A. Butterfield, Dan M. Griffin, Philip L. Stephenson
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Publication number: 20020071479Abstract: A method and apparatus for operating a communication system having subscriber stations (SSs) and at least one base station (BS). The communication system operates in accordance with a method that includes steps of: (a) arranging the forward link and the reverse link to operate with a common waveform; and (b) using common forward link and reverse link signal processing circuitry in the BS and individual ones of the SSs. A further step provides switching circuitry for cross-connecting RF signal paths for enabling one of the SSs to function as a BS. The common waveform enables essential parameters of the forward link and the reverse link to be identical, where the essential parameters can include some or all of the following parameters: the modulation format, chip rate, symbol rate, bit rate, frame rate, superframe rate, frame structure, error control coding scheme, sync words, and control field structure. Other parameters may also be made equal between the forward link and the reverse link.Type: ApplicationFiled: April 9, 2001Publication date: June 13, 2002Applicant: L-3 Communications CorporationInventors: Thomas R. Giallorenzi, Eric K. Hall, Richard B. Ertel, Philip L. Stephenson, Dan M. Griffin, Lee A. Butterfield
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Publication number: 20020051462Abstract: This invention provides a highly flexible multiplexing scheme for Direct Sequence CDMA systems enabling the CDMA system to flexibly allocate CDMA channel resources between packet-switched broadcast channels and fast-circuit-switched dedicated channels in order to optimize system throughput. A method and system are provided for operating a communication system. The method has steps of: flexibly allocating CDMA channel resources between packet-switched broadcast channels and fast-circuit-switched dedicated channels in order to optimize system throughput, and employing a side channel as required to send all or a part of a total amount of data, depending on the total amount of the data. A bandwidth allocation scheme allocates a set of CDMA channels for burst packet-switched channels, and data is time division multiplexed over the set of burst CDMA channels providing a wide bandwidth data pipe for packet-switched data..Type: ApplicationFiled: April 9, 2001Publication date: May 2, 2002Applicant: L-3 Communications CorporationInventors: Richard B. Ertel, Eric K. Hall, Thomas R. Giallorenzi, Philip L. Stephenson, Johnny M. Harris, Edward P. Newren
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Publication number: 20020051435Abstract: A communications system employs the use of both synchronous CDMA and FDMA to provide a variable bandwidth waveform with multiple bonded transmitters and receivers that are agile in both frequency and PN code to permit a variable bandwidth and variable rate multiple access system. In a first aspect the teachings provide the use of both CDMA and FDMA together to enable an improved concentration efficiency by making a larger pool of bandwidth available to each user. In a second aspect these teachings enable channel bonding across both code space and frequency space, thus making the system capable of operating within a variable (not necessarily contiguous) bandwidth and at a finely variable rate.Type: ApplicationFiled: April 9, 2001Publication date: May 2, 2002Applicant: L-3 Communications CorporationInventors: Thomas R. Giallorenzi, Eric K. Hall, Richard B. Ertel, Philip L. Stephenson, Dan M. Griffin, Lee A. Butterfield
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Patent number: 6061339Abstract: A method is disclosed for operating a fixed wireless system having a radio base unit (RBU) that uses a code division multiple access (CDMA) airlink for communicating with a plurality of subscriber units (SUs). The method includes steps of (a) estimating a signal to noise ratio (SNR) of the FWS; (b) comparing the estimated SNR to a threshold SNR value; and (c) one of allowing service to another SU or not allowing service to another SU based on the result of the step of comparing. The step of estimating preferably uses a normalized SNR, and further employs the use of a null PN code detection technique. More particularly, the step of estimating determines a normalized signal to noise ratio given by Eb/No=20 log (SUT/MUT)-xdB, wherein SUT represents a single user test measurement, wherein MUT represents a multiple user test measurement, and wherein xdB is an adjustment factor. Other types of CDMA systems may also use this technique.Type: GrantFiled: December 10, 1997Date of Patent: May 9, 2000Assignee: L-3 Communications CorporationInventors: Leon L Nieczyporowicz, Thomas R Giallorenzi, Philip L Stephenson, Randal R Sylvester
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Patent number: 6023462Abstract: Disclosed is a method for operating a fixed wireless system (FWS) having a radio base unit (RBU) that uses a code division multiple access (CDMA) airlink for communicating with a plurality of subscriber units (SUs) within a coverage area of the RBU. The method includes establishing, from a set of pseudonoise (PN) spreading codes, a subset of PN spreading codes that are currently assigned to SUs and a subset of PN spreading codes that are currently not assigned to SUs. The method further ranks the PN spreading codes from the subset of non-assigned PN spreading codes by an amount of interference experienced by the use of each non-assigned PN spreading code, and assigns to an SU requiring a PN spreading code a PN spreading code from the set of non-assigned PN spreading codes that is ranked as having a least amount of interference.Type: GrantFiled: December 10, 1997Date of Patent: February 8, 2000Assignee: L-3 Communications CorporationInventors: Leon L Nieczyporowicz, Philip L Stephenson, Thomas R Giallorenzi, Robert W Steagall
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Patent number: 5966373Abstract: Disclosed is a method for transmitting information in a CDMA communication system, the method including steps of (a) multiplexing data and control information into a data stream; (b) encoding the data stream to form a stream of encoded I/Q symbol pairs; (c) inserting synchronization information into the stream of encoded I/Q symbol pairs; and (d) spreading the encoded I/Q symbol pairs and the inserted synchronization information using a same pseudonoise (pn) spreading code prior to transmission as a frame. The preferred frame structure includes an unencoded synchronization field followed by a plurality of multi-byte data fields. Individual ones of the plurality of data fields are separated by a control message field. Individual ones of the control message fields contain a single byte of a multi-byte control message frame.Type: GrantFiled: December 10, 1997Date of Patent: October 12, 1999Assignee: L-3 Communications CorporationInventors: Philip L Stephenson, Thomas R Giallorenzi, Johnny M Harris, Lee A Butterfield, Michael J Hurst, Dan M. Griffin, Rolf K. Thompson