Patents Represented by Attorney David R. Gildea
  • Patent number: 6002721
    Abstract: A method and apparatus for estimating a carrier frequency of an incoming signal. The carrier frequency estimator determines the phase difference between the phases for two successive modulation symbols when the two successive modulation symbols are within a particular magnitude range having at least two evenly spaced modulation phase states. The carrier frequency estimator includes a magnitude selector for selecting modulation symbols within the particular magnitude range and a phase subtractor coupled to the magnitude selector for determining phase differences between the successive modulation symbol phases. A signal receiver of the present invention uses the phase differences for tuning a locally generated frequency for tracking a carrier frequency of an incoming radio frequency (RF) signal.
    Type: Grant
    Filed: July 20, 1998
    Date of Patent: December 14, 1999
    Assignee: Stanford Telecommunications, Inc.
    Inventors: Ahmed M. Said, Herbert W. Huang
  • Patent number: 5969561
    Abstract: A bipolar radio frequency (RF) integrated circuit having a functional equivalent of a PIN diode. The RF integrated circuit includes a low frequency lateral PNP transistor having an emitter having a P+ region, a collector having a P+ region, a base having an N+ region and an N region having a current dependent stored charge having a relatively low level when no current is flowing between the emitter and a junction connecting the base and collector. An RF resistance between the emitter and the junction is controlled by a bias applied from the emitter to the junction. By varying the bias, the low frequency lateral PNP transistor from the emitter to the junction is used as a variable RF resistor or as an RF signal carrying component in a variable attenuator or RF switch.
    Type: Grant
    Filed: March 5, 1998
    Date of Patent: October 19, 1999
    Assignee: Diablo Research Company, LLC
    Inventor: Michael E. McGillan
  • Patent number: 5944770
    Abstract: A method and an apparatus using a low Earth orbiting (LEO) satellite signal to augment the Global Positioning System (GPS) for finding a location vector between a GPS user receiver and a GPS reference receiver. The GPS user receiver computes a LEO user-reference carrier phase difference and a GPS user-reference carrier phase difference for the LEO satellite signal and a GPS satellite signal, respectively, received simultaneously at the GPS user receiver and the GPS reference receiver. Carrier phase double differences are computed from a difference between the GPS user-reference carrier phases from two GPS satellites and either the LEO user-reference carrier phases from two LEO satellites or the GPS user-reference carrier phase from one GPS satellite and the LEO user-reference carrier phase from one LEO satellite. The location vector is computed from a difference between the double differences for two satellite geometries.
    Type: Grant
    Filed: November 28, 1997
    Date of Patent: August 31, 1999
    Assignee: Trimble Navigation Limited
    Inventors: Per K. Enge, Nicholas Charles Talbot
  • Patent number: 5926776
    Abstract: A smart thermostat having a transceiver for two-way communication with an energy provider. The smart thermostat includes a temperature sensor for measuring a temperature, a user interface for displaying and receiving information to and from a user, a port connecting to a cooling or heating device, a processor, and the transceiver. The transceiver receives a current energy price from an energy provider. The user interface receives temperature setpoints and associated acceptable energy costs. The processor issues a control signal to the cooling or heating device to operate when the temperature is different than the temperature setpoint and the acceptable energy cost is not greater than the current price of energy. The transceiver transmits information for the control signal, temperature setpoints and associated costs to the energy provider.
    Type: Grant
    Filed: June 4, 1997
    Date of Patent: July 20, 1999
    Assignee: Gas Research Institute
    Inventors: Charles A. Glorioso, William Wade Bassett, Robert M. Russ, Jr.
  • Patent number: 5914672
    Abstract: A system of multiple remote meter interfaces (RMI)s and multiple base stations. Each base station concentrates meter reading information received from several RMIs and passes the concentrated information up through a wide area network to a central office. Each RMI may be field installed to communicate with only one base station. Each base station maintains an identification (ID) list having its own base station ID and the RMI IDs for the RMIs with which the base station is enabled to communicate. To install or reinstall a particular RMI without communicating with the central office, a field installer tool operated by a field installation or repair person establishes communication with the base station using the base station ID, then directs the base station to add the RMI ID for the particular RMI to the ID list.
    Type: Grant
    Filed: June 13, 1997
    Date of Patent: June 22, 1999
    Assignee: Whisper Communications Incorporated
    Inventors: Charles A. Glorioso, Ali R. Naddaf
  • Patent number: 5914956
    Abstract: A cache apparatus and method for improving the connection capacity of an Asynchronous Transfer Mode (ATM) switch. The cache updates the ATM switch with information for configuring connections while maintaining a separate connection table. Incoming data cells are examined by a cell router and routed either directly to the switch, if a connection is already configured, or to a cell holding area while the connection is being set up in the switch. Unused or underused connections are detected in the connection table by a reclaim ager and marked underused. An updater then reviews the connection table to use the connection resources represented by the underused connections for configuring connections for the data cell stored in the cell holding area.
    Type: Grant
    Filed: February 3, 1997
    Date of Patent: June 22, 1999
    Inventor: Joel R. Williams
  • Patent number: 5909640
    Abstract: A wireless communication system with one or more remote transceivers for transmitting a wireless data signal at an actual frequency that is different than the expected frequency and a base transceiver that can automatically adjust to receive the actual frequency. Each remote transceiver is adapted to initiate a wireless data signal at a selected time that is unique to that remote transceiver. The expected frequency is sequentially pre-determined in a pseudo-random sequence with each remote transceiver having a unique sequence. The base transceiver can respond to the remote transceiver at the actual frequency. Both the remote transceiver and the base transceiver can convert the wireless signals in a single step to baseband.
    Type: Grant
    Filed: October 6, 1997
    Date of Patent: June 1, 1999
    Assignee: Whisper Communications, Inc.
    Inventors: Leland M. Farrer, Joseph S. Chan, Robert F. Garry, Jr., Charles A. Glorioso, Norman F. Krasner
  • Patent number: 5898684
    Abstract: A time division multiple access (TDMA) burst receiver and a method for recognizing and providing a time-of-arrival of a TDMA burst transmission having a selected preamble. The TDMA burst receiver includes a blanker for blanking the TDMA burst transmission when the signal level exceeds a pre-selected noise threshold, a signal threshold detector for providing a first tentative time-of-arrival when a correlation of the TDMA burst transmission and the selected preamble exceeds a first threshold and a second tentative time-of-arrival only when the correlation exceeds a second threshold within a selected time period following the first tentative time-of-arrival, and a state machine for providing an operational time-of-arrival corresponding to the first tentative time-of-arrival when the second tentative time-of-arrival is not received and the second tentative time-of-arrival when the second time-of-arrival is received.
    Type: Grant
    Filed: December 19, 1996
    Date of Patent: April 27, 1999
    Assignee: Stanford Telecommunications, Inc.
    Inventors: Bruce J. Currivan, Allen P. Edwards
  • Patent number: 5883594
    Abstract: A message system, global positioning system (GPS) receiver apparatus, and method for providing a fast time to first location fix and a low average power consumption in a GPS receiver. The message system includes a GPS base station for receiving a GPS signal and providing GPS acquisition and location information including GPS satellite visibility, health, and ephemeris; and a message system manager for transmitting a radio message signal including a wakeup call and the GPS information. A message transceiver or receiver receives the radio message signal and passes the wakeup call and GPS information to a GPS receiver having a low power standby mode. The GPS receiver awakens from the standby mode and enters an operational mode for using the GPS information for acquiring the GPS signal and deriving the first location fix. In a first embodiment, the GPS receiver initiates the first fix by requesting the message transceiver to transmit a radio request signal.
    Type: Grant
    Filed: February 20, 1997
    Date of Patent: March 16, 1999
    Assignee: Trimble Navigation Limited
    Inventor: Chung Y. Lau
  • Patent number: 5883596
    Abstract: A GPS timing receiver for providing a GPS-derived time signal. The GPS timing receiver includes a filter for filtering a GPS signal to a certain information bandwidth, a reference clock for generating a reference clock signal having a clock rate at least ten times the information bandwidth, a sampler using the reference clock signal for oversampling the filtered GPS signal, a correlation subsystem including a microprocessor for correlating the sampled GPS signal to the reference clock signal to measure a time difference between the GPS signal and the reference clock signal, and a time clock to issue a GPS-derived time signal based upon the reference clock signal and adjusted by the measured time difference in increments of the period of the reference clock signal. An optional frequency multiplier multiplies the reference clock rate enabling the time clock to adjust the GPS-derived time signal in increments of the period of the frequency multiplied reference clock signal.
    Type: Grant
    Filed: November 13, 1997
    Date of Patent: March 16, 1999
    Assignee: Trimble Navigation Limited
    Inventor: Eric B. Rodal
  • Patent number: 5880464
    Abstract: A meter reader for reading a meter by reading a shadow made by a meter pointer on the face of the meter. The meter reader includes a light source for shining a light toward the meter, a pulse control circuit for pulsing the light source, two light sensors for receiving reflections of the pulsed light from two sections of the face, a detection circuit for detecting the intensity of the reflections received by each of the sensors, a microprocessor system for calculating an intensity relationship between the intensities received by each of the sensors, a counter for incrementing a meter readout count when the intensity relationship varies indicating that the shadow has passed over both sections of the meter face, and a transmitter for transmitting the meter readout count in a meter readout signal.
    Type: Grant
    Filed: June 9, 1997
    Date of Patent: March 9, 1999
    Assignee: Diablo Research Corporation
    Inventor: Nick G. Vrionis
  • Patent number: 5854605
    Abstract: A GPS receiver and a method for improving time to first fix (TTFF). The GPS receiver includes an internal clock for maintaining an approximate clock time during a standby mode and a microprocessor system including a data bit timer code, a temperature compensation code, and a learned time adjustment code. When the GPS receiver enters an operational mode, the data bit timer code instructs the microprocessor system for determining a GPS-based clock time by aligning the approximate clock time according to a time-of-arrival of a GPS data bit when the approximate clock time and the GPS-based clock time are estimated to be within a correction range of ten milliseconds. The temperature compensation code and a learned time adjustment code include instructions for using a stored frequency/temperature characteristic and a learned time correction, respectively, for estimating and compensating for time drift that has occurred during the standby mode.
    Type: Grant
    Filed: July 5, 1996
    Date of Patent: December 29, 1998
    Assignee: Trimble Navigation Limited
    Inventor: David R. Gildea
  • Patent number: 5847680
    Abstract: A carrier ambiguity detector for resolving a 1/2 cycle carrier phase ambiguity in an incoming GPS signal before the arrival of the next preamble by detecting a match or an inverted match between an internally stored expected data message and the incoming data in the remaining subframe before the arrival of the next preamble. The carrier ambiguity detector of the present invention includes a buffer for buffering incoming data, a data memory for storing time-tagged expected data, a data pointer for selecting certain expected data corresponding to a GPS-based time that is synchronized to the incoming data, non-inverting and inverting comparators for comparing the buffered data to the expected data, and a data compare detector coupled to the comparators for indicating a non-inverted or an inverted match for a zero degree or a one-hundred eighty degree resolution, respectively, of carrier phase information.
    Type: Grant
    Filed: December 5, 1997
    Date of Patent: December 8, 1998
    Assignee: Trimble Navigation Limited
    Inventor: Paul W. McBurney
  • Patent number: 5848376
    Abstract: A Global Positioning System (GPS) receiving apparatus that is powered by a control or data interface signal from a computing apparatus. The GPS receiving apparatus includes a GPS receiver for receiving GPS satellite signals and providing GPS-derived location information and a converter for converting the interface signal to operating power signal for operating the GPS receiver. Optionally, the GPS receiver includes a power controller for controlling a duty cycle of the operating power in the GPS receiver in order to not exceed the power available from the interface signal. The interface signal is transmitted according to an interface standard such as RS232, RS422, or PC parallel.
    Type: Grant
    Filed: November 13, 1997
    Date of Patent: December 8, 1998
    Assignee: Trimble Navigation Limited
    Inventors: Glenn C. Steiner, Lloyd H. Banta
  • Patent number: 5831577
    Abstract: A GPS/radio antenna for receiving a GPS satellite signal and a DGPS radio signal. The GPS/radio antenna includes a GPS antenna using a microstrip antenna element for receiving the GPS signal having GPS location determination information, a radio antenna for receiving a DGPS radio signal in the FM broadcast frequency range having DGPS corrections, an enclosure, and a cable. The GPS/radio antenna may be included in a GPS/DGPS receiver system also including a receiver unit with an FM DGPS receiver for demodulating the DGPS radio signal and providing DGPS corrections, and a differential-ready GPS receiver for providing a differentially-corrected GPS location.
    Type: Grant
    Filed: July 28, 1997
    Date of Patent: November 3, 1998
    Assignee: Trimble Navigation Limited
    Inventors: Mark E. Nichols, Eric B. Rodal
  • Patent number: 5832247
    Abstract: A peripheral component interconnect (PCI) global positioning system (GPS) card for receiving a GPS signal. In a first embodiment the PCI card includes a GPS downconverter. In a second embodiment the PCI card including the GPS downconverter is integrated into a personal computer for correlating a GPS signal and computing a GPS location. In a third embodiment the PCI card includes a GPS downconverter and a GPS correlator. In a fourth embodiment the PCI card including the GPS downconverter and the GPS correlator is integrated into a personal computer for computing a GPS location.
    Type: Grant
    Filed: July 31, 1997
    Date of Patent: November 3, 1998
    Assignee: Trimble Navigation Limited
    Inventors: David R. Gildea, Mark L. Nagel
  • Patent number: 5832493
    Abstract: A flash memory using branded sectors for managing data files. The flash memory is divided into separately erasable blocks where each block may only be erased in its entirety. Each erasable block includes several file sectors, a sector allocation table (SAT) including an SAT record for each file sector, and a block information record (BIR) including status and an erasure count for the block. Each file sector may be designated as a file data sector, a file header sector, or block erasure sector. The data sectors include a data segment of one of the data files and is branded by a file identification and a sequence number. The brand and the size of the file sectors are used for locating the data sector for accessing the data segment.
    Type: Grant
    Filed: April 24, 1997
    Date of Patent: November 3, 1998
    Assignee: Trimble Navigation Limited
    Inventors: Jonathan Miles Marshall, Charles David Hope Manning
  • Patent number: 5812961
    Abstract: A method and an apparatus using a low Earth orbiting (LEO) satellite signal to augment the Global Positioning System (GPS) for finding a location vector between a GPS user receiver and a GPS reference receiver. The GPS user receiver computes a LEO user-reference carrier phase difference and a GPS user-reference carrier phase difference for the LEO satellite signal and a GPS satellite signal, respectively, received simultaneously at the GPS user receiver and the GPS reference receiver. Carrier phase double differences are computed from a difference between the GPS user-reference carrier phases from two GPS satellites and either the LEO user-reference carrier phases from two LEO satellites or the GPS user-reference carrier phase from one GPS satellite and the LEO user-reference carrier phase from one LEO satellite. The location vector is computed from a difference between the double differences for two satellite geometries.
    Type: Grant
    Filed: December 28, 1995
    Date of Patent: September 22, 1998
    Assignee: Trimble Navigation Limited
    Inventors: Per K. Enge, Nicholas Charles Talbot
  • Patent number: 5798732
    Abstract: A global positioning system (GPS) receiver and a method having a fast time to first fix (TTFF) using GPS signal Doppler frequency shifts for correcting the local clock time and using information for an expected GPS message for synchronizing the corrected local clock time to GPS time. The GPS receiver includes radio frequency (RF) circuitry for receiving and downconverting a spread spectrum GPS satellite signal, a correlator for despreading the downconverted GPS signal and providing a GPS bit stream, a clock for providing a local time, and a processor including an executable code.
    Type: Grant
    Filed: September 19, 1996
    Date of Patent: August 25, 1998
    Assignee: Trimble Navigation Limited
    Inventor: Ralph F. Eshenbach
  • Patent number: 5791834
    Abstract: A door drilling fixture for drilling a long straight longitudinal hole in a door. The fixture includes an elongated frame having a U-shaped cross-section for mounting about the hinged edge of a door and an arm projecting from and pivotally engaged to the frame for guiding a long drill bit. The door is placed between the right and left sections and the door edge flat against the center section of the U-shaped frame. Two hold-down bolts thread through upper and lower portions of the left section of the U-shaped frame to press the door against the right section of the U-shaped frame. Slots in the frame mechanically isolate the upper and lower portions of the left section from the middle portion of the center section. The arm houses two spaced apart drill bushings having a center line for rotationally engaging and guiding the drill bit through the drill bit aperture and into the edge of a door.
    Type: Grant
    Filed: April 25, 1997
    Date of Patent: August 11, 1998
    Inventor: Raymond E. Zehrung