Patents by Inventor Christopher W. Rice

Christopher W. Rice 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).

  • Patent number: 6643504
    Abstract: Automatic activation (i.e., first time access) of digital wireless/cellular mobile telephones with a private/localized wireless/cellular system (i.e. a secondary system) occurs within an area having an overlapping macrocellular primary wireless communication system (i.e., a dominant system). Operation of the secondary access procedure is achieved by shielding/masking an access and authentication process for the secondary system from interference from the control signal levels of the dominant wireless communication system. During the first time access, the secondary system is supplied with the SID and MIN and ESN numbers for authentication and resultant access.
    Type: Grant
    Filed: July 10, 2000
    Date of Patent: November 4, 2003
    Assignee: AT&T Corp.
    Inventors: Albert T. Chow, Richard Henry Erving, Robert Raymond Miller, II, Christopher W. Rice, Jesse Eugene Russell, Wenchu Ying
  • Publication number: 20030156685
    Abstract: A subscriber loop test apparatus relates to the testing of a subscriber loop by the use of a touchtone telephone. The touchstone buttons on a telephone provide Dual-Tone, Multiple Frequencies for each key pressed. For example, referring to FIG. 1, pressing the ‘3’ key causes tones at 697 and 1477 Hz to be sent across the telephone line. Pressing a sequence of keys provides discrete coverage of the frequency band from 697 to 1477 Hz, through the use of the touchtone telephone. The frequency band from 697 to 1477 Hz can be characterized in this fashion. Information about the line: loop loss (loop length), presence of bridge taps (i.e., excessively long bridge taps in particular) or loading coils, and the presence of Digital Loop Carriers (DLCs), et cetera. The use of the switch-hook flash provides the ability to determine the channel (impulse) response of the loop, including any noise and hum that may be on the loop due to imbalance or coupled interference.
    Type: Application
    Filed: February 12, 2002
    Publication date: August 21, 2003
    Inventors: Richard Henry Erving, Maura Elizabeth Marcus, Robert Raymond Miller, Christopher W. Rice
  • Patent number: 6580710
    Abstract: Broadband services are provided to customer premises, whose existing premise wiring does not have broadband capability, by disaggregating the various signals, including broadband services, supplied to the premise from a broadband communication link at the customer premise's edge, so that the existing POTS wires, within the customer premises, may function as separate channels for varied broadband and narrow band services. Intra premises broad band services are disaggregated so that POTS service responds normally to the network while internal LAN networks operate independently of the outside system network.
    Type: Grant
    Filed: November 19, 1999
    Date of Patent: June 17, 2003
    Assignee: AT&T Corp.
    Inventors: Donald John Bowen, Richard Henry Erving, Robert Raymond Miller, II, John F. Murray, Christopher W. Rice, Jesse Eugene Russell
  • Publication number: 20030060178
    Abstract: The present invention is a system for increasing Signal-to-Noise Ratio (SNR) in a wireless communication system comprising a plurality of antennas each antenna providing a signal, a device for selecting a subset of signals provided by the plurality of antennas, a maximum ratio combiner for summing the selected subset of signals provided by the plurality of antennas, and a decision device for measuring the selected subset of signals against a predefined threshold. The device for selecting the subset of signals is coupled to the plurality of antennas. The maximum ratio combiner is coupled to the selected subset of signals and the decision device for measuring the selected subset of signals against a predefined threshold. The decision device is coupled to the selecting device such that one selected signal of the selected subset of signals is replaced by an unused signal provided by the plurality of antennas.
    Type: Application
    Filed: September 25, 2001
    Publication date: March 27, 2003
    Inventors: Saeed S. Ghassemzadeh, Richard Henry Erving, Robert Raymond Miller, Christopher W. Rice
  • Publication number: 20030058827
    Abstract: An architecture is described for providing IP push-to-talk (IPP2T) service using a wireless local area network (WLAN) serving a plurality of subscriber terminals (STs), having at least one broadband access network terminal (BANT), the BANT coupled to and interacting with at least one of a plurality of Access Points (APs) via a local area network (LAN), the plurality of APs in communication with the plurality of subscriber terminals; a multicast-enabled network, the multicast-enabled network coupled to and interacting with at least one BANT via a broadband access network; an IP network coupled to, and interacting with, the multicast-enabled network via an edge router; and a WLAN mobile radio service (WLMRS) controller (WLMRSC) coupled to and interacting with the IP network via a multicast-enabled router (MR).
    Type: Application
    Filed: July 26, 2002
    Publication date: March 27, 2003
    Applicant: AT&T Corp.
    Inventors: Albert T. Chow, Robert Raymond Miller, John F. Murray, Christopher W. Rice
  • Publication number: 20030053434
    Abstract: A wireless subscriber terminal (ST) for use with IP push-to-talk (IPP2T) service using a wireless local area network (WLAN) operating in a plurality of modes, including a mobile terminal having an ability to communicate over the air to a wireless Access Point (AP), the mobile terminal further programmable to use conventional WLAN protocols, and a method for operating the wireless terminal are described.
    Type: Application
    Filed: July 26, 2002
    Publication date: March 20, 2003
    Applicant: AT&T Corp.
    Inventors: Albert T. Chow, Robert Raymond Miller, John F. Murray, Christopher W. Rice
  • Patent number: 6424215
    Abstract: High efficiency and high power output are attained in a multi-tone FF RF amplifier by eliminating fundamentals in a first loop and then operating on the IMD products only in a second loop. Since lower power tones are adjusted in the IMD product reduction, less complex, lower power processing circuitry is required and higher efficiency is realized since both amplifiers add in-phase and approximately equally at the RF output.
    Type: Grant
    Filed: April 12, 2001
    Date of Patent: July 23, 2002
    Assignee: AT&T Corp.
    Inventor: Christopher W Rice
  • Patent number: 6388539
    Abstract: Parallel combined redundancy and switched redundancy are provided for active RF devices (i.e., amplifiers) in a cable plant system with a switch/coupler circuit of passive magnetic devices and switches that respond to an amplifier failure by switching the circuit into a combined or switched redundancy mode as needed to maintain a suitable dynamic range of operation. In either redundancy mode, the switch/coupler circuit operates with a constant 3dB reduction of dynamic range.
    Type: Grant
    Filed: April 16, 2001
    Date of Patent: May 14, 2002
    Assignee: AT&T Corp.
    Inventor: Christopher W Rice
  • Patent number: 6198346
    Abstract: A multi-tone signal amplifier topology and an amplifying method in which a first amplifier outputs a first signal having at least one fundamental frequency signal and a first distortion signal. A second amplifier outputs a second signal that has a fundamental frequency signal corresponding to each fundamental frequency signal of the first signal and a second distortion signal. Each fundamental frequency signal of the second signal is substantially in-phase with the corresponding fundamental frequency signal of the first signal, while the second distortion signal is substantially 180° out-of-phase with the first distortion signal. An output coupler combines the first and second signals to form a third signal having the corresponding fundamental frequency signals of the first and second signals constructively combined and a third distortion signal that is a difference between the first distortion signal and the second distortion signal.
    Type: Grant
    Filed: November 18, 1998
    Date of Patent: March 6, 2001
    Assignee: AT&T Corp.
    Inventors: Christopher W. Rice, Irene Triantafillou
  • Patent number: 5929701
    Abstract: A dual loop feed forward amplifier and method of amplification. The dual loop feed forward amplifier contains at least two amplification stages that introduce unwanted intermodulation products into the output signal. A spreading tone is introduced to the RF signal in between the first and second amplification stages. The spreading tone is created by a bi-phase modulator that spreads an input tone in accordance with a spread PN-code. After the spreading tone is amplified by the subsequent stages of the feed forward amplifier, the spreading tone is despread by the same spread PN-code. The resulting output tone is mixed with the original input tone. The output of the mixer is then filtered to remove the unwanted spurious products produced by the mixer. The feed forward amplifier is then actively adjusted by a computer controller to reduce any difference between input tone and the output tone until a desired signal-to-interference ratio is obtained.
    Type: Grant
    Filed: December 13, 1996
    Date of Patent: July 27, 1999
    Assignee: AT&T Corp.
    Inventor: Christopher W. Rice
  • Patent number: 5917387
    Abstract: In an RF filter having an input terminal, an output terminal, a plurality of resonator elements, and a plurality of coupling reactances for coupling one resonator element to another resonator element, for coupling the input terminal to a resonator element, and for coupling the output terminal to a resonator element, techniques are disclosed for providing an RF filter having an electronically tunable center frequency and an electronically tunable bandwidth. According to a specific embodiment disclosed herein, a first shunt reactance is provided from the input terminal to ground, and a second shunt reactance is provided from the output terminal to ground. The values of the coupling reactances remain constant, while the values of the resonator elements, the first shunt reactance, and the second shunt reactance are tuned to provide a specified filter bandwidth and/or a specified center frequency.
    Type: Grant
    Filed: September 27, 1996
    Date of Patent: June 29, 1999
    Assignee: Lucent Technologies Inc.
    Inventors: Christopher W. Rice, Harry R. Worstell
  • Patent number: 5208553
    Abstract: An n-stage amplifier circuit includes n+1 directional couplers connected in series between the circuit input, the amplifier stages, and the circuit output. Each coupler includes first and third ports forming an inverting interface, and second and fourth ports forming a non-inverting interface, the ports being coupled through suitable windings. Feedback lines are connected between adjacent successive couplers. The interfaces of the couplers are connected such that feedback loops covering one or more contiguous successive amplifier stages provide negative feedback for the amplifier circuit.
    Type: Grant
    Filed: April 5, 1991
    Date of Patent: May 4, 1993
    Assignee: Q-Bit Corporation
    Inventor: Christopher W. Rice
  • Patent number: 4795922
    Abstract: An amplitude/phase discriminator network the entirety of which is integrated on the same (GaAs) semiconductor chip, obtains a quadrature phase split through the use of a pair of orthogonal phase generators each of which comprises an all-pass network coupled with a pair of differential amplifiers. An unknown signal of interest, the phase and amplitude of which are to be derived, is applied to one pair of all-pass networks, while a reference signal, the amplitude and phase of which are known, is applied to the other pair of all-pass networks. Four quadrature outputs produced by the differential amplifiers contained within the pair of orthogonal phase generators are selectively coupled to a signal combining stage comprised of a diode detector-low pass filter network.
    Type: Grant
    Filed: April 9, 1987
    Date of Patent: January 3, 1989
    Assignee: Harris Corp.
    Inventors: Christopher W. Rice, Seward T. Salvage