Patents Represented by Attorney, Agent or Law Firm Richard A. Sonnentag
  • Patent number: 5493563
    Abstract: A communication system utilizes rotated bursts of voice channels to implement mobile assisted handoff (MAHO). Mobile stations measure the voice channels of adjacent cells as hopping frequencies are rotated from frame-to-frame of the communication system. Measurement of the voice channels of adjacent cells can be performed by mobile stations during timeslots subsequent to their receive and transmission so that measurement during a timeslot dedicated to a control channel related to the adjacent cells is not necessary.
    Type: Grant
    Filed: July 26, 1993
    Date of Patent: February 20, 1996
    Assignee: Motorola, Inc.
    Inventors: Walt Rozanski, Kamyar Rohani
  • Patent number: 5488638
    Abstract: A diversity receiver (200) recovers clock information from different versions (301, 302) of a transmitted signal (106). The diversity receiver (200) receives the different versions (301, 302), converts the versions (301, 302) into samples (307, 317) via a common sampling clock (309). The receiver (200) then correlates the samples (307, 317) with like synchronization patterns and uses clock information from the received version (307 or 317) which gives the greatest correlation output signal (504, 506) for data detection in one of two detectors (323, 326). The choice of detectors (323, 326) is determined by the diversity receiver (200) by counting the total number of bit-differences output by detectors (323, 326) over a predetermined time period and comparing the total bit-differences with a number represented by a threshold signal (330).
    Type: Grant
    Filed: February 22, 1994
    Date of Patent: January 30, 1996
    Assignee: Motorola, Inc.
    Inventors: Henry L. Kazecki, John W. Diehl
  • Patent number: 5475686
    Abstract: A communication system (101) concentrates the output of variable rate transcoders (XCDRs 203, 206, 209) to realize an increase in T1 Megastream link capacity. Line interface cards (212, 213) multiplex a generic transcoder/rate adapter unit (GTRAU) format to a concentrated transcoder/rate adapter unit (CTRAU) format based on a determined rate of the data being output from the variable rate transcoders (XCDRs 203, 206, 209). An increase in T1 Megastream link capacity is realized by efficiently concentrating full, half, quarter, and eighth rate channels into a single DS0 for transmission over the T1 Megastream.
    Type: Grant
    Filed: December 28, 1992
    Date of Patent: December 12, 1995
    Assignee: Motorola, Inc.
    Inventors: Michael J. Bach, William R. Bayer
  • Patent number: 5455962
    Abstract: A cellular communication system (50) is offered wherein communicated signals are exchanged on an indexed uplink communication resource and a non-indexed downlink communication resource. The non-indexed downlink communication format allows communication units to identify proximate service providers without knowledge of the index algorithm. The indexed signal transmitted by a user communication unit improves noise immunity in a signal transceived on the uplink. Signal quality is improved on the downlink through the use of selectable diversity antennas (22 or 23).
    Type: Grant
    Filed: June 3, 1994
    Date of Patent: October 3, 1995
    Assignee: Motorola, Inc.
    Inventor: Michael D. Kotzin
  • Patent number: 5451946
    Abstract: A digital-to-analog converter (DAC, 300) utilizes a coarse DAC (306) and fine DAC (315) to produce an analog output signal having both low glitch energy and good linearity performance. The DAC (300) also uses an error table (312) to store correction data generated through a calibration procedure. Outputs (307, 311) from each DAC (306, 315) are summed to produce an analog output signal which exhibits better linearity than does the output (307) of the coarse DAC (306) alone.
    Type: Grant
    Filed: June 28, 1993
    Date of Patent: September 19, 1995
    Assignee: Motorola Inc.
    Inventors: Paul F. Smith, Danny T. Pinckley
  • Patent number: 5446370
    Abstract: A transceiver (203) instructs a RF switch matrix (200) to direct its output to any one of M outputs and likewise sends information related to the power and frequency of the RF input signal and the switched output to an OMC (112). Each output of the matrix (200) is adjusted by an attenuator bank (218) and fed to a spectrum analyzer (233). OMC (112) relays the power, frequency and switched output information to a computer (239) which instructs the spectrum analyzer (233) to perform a power measurement at the frequency of the RF input signal. The computer (239) then determines which outputs of the matrix (200) were switched based on the power level of the RF input signal, the measured power level of the adjusted output signal and a relationship of the different predetermined levels within attenuator bank (218) and verifies by comparison to the switched output information.
    Type: Grant
    Filed: September 30, 1993
    Date of Patent: August 29, 1995
    Assignee: Motorola, Inc.
    Inventor: John Voight
  • Patent number: 5446727
    Abstract: A coherent reverse channel, a per-chip spreading function, orthogonal spreading functions and a time alignment of all traffic channels are implemented such that the main signal of each channel arrives at a base-station within a fraction of a chip of one another in accordance with the invention. With this, the orthogonality among all channels is maintained, and, when demodulated, all channels except the channel of interest provides a cross-correlation of substantially zero with respect to the remaining signals.
    Type: Grant
    Filed: November 30, 1993
    Date of Patent: August 29, 1995
    Assignee: Motorola Inc.
    Inventors: Eugene J. Bruckert, Richard A. Sonnentag
  • Patent number: 5442661
    Abstract: A coherent RAKE receiver utilizes a "blind block" path gain estimation scheme, based on a maximum likelihood criterion, to estimate path gains in the receiver. It is "blind" in that preliminary hard decisions on coded bits (i.e., coded bits from the corrupt transmitted signal) are not used. Instead, a form of soft decisions are used. It is a "block" scheme in that the complex path gains are estimated for an isolated block, for example a block of B correlator outputs. The path gains varying with time are approximated to be linear in time such that the average path gain and the slope of the path gain per path can be utilized to estimate the path gain. The path gain estimation scheme overcomes the shortcomings of typical CDMA systems where there is no assurance of continuous transmission (except for full-rate 9600 b/s transmission) upon which to base a FIR filter-type prediction scheme.
    Type: Grant
    Filed: August 13, 1993
    Date of Patent: August 15, 1995
    Assignee: Motorola Inc.
    Inventor: David D. Falconer
  • Patent number: 5442681
    Abstract: A communication system employs a method for exchanging communicated signals between a remote base site (e.g., 63) and a central site (205) on a communication resource (e.g., 77) assigned to the remote base site (63). The central site (205) or the remote base site (63) determines that a signal must be exchanged between the remote base site (63) and the central site (205). The remote base site (63) then allocates the communication resource (77) for exchanging the signal from those communication resources (e.g., 76 and 77) assigned to the remote base site (63) for exchanging signals with communication units (e.g., 18) in the service coverage area (53) of the remote base site (63).
    Type: Grant
    Filed: May 3, 1993
    Date of Patent: August 15, 1995
    Assignee: Motorola Inc.
    Inventors: Michael D. Kotzin, Valy Lev, Stephen L. Spear
  • Patent number: 5412686
    Abstract: A method and apparatus is provided for estimating signal power. This is accomplished by demodulating a received communication signal to derive a stream of samples. These samples may consist of either reference samples, data samples, or a combination thereof. An estimate of the power of the received communication signal is then generated as a function of the stream of samples. The signal power estimate may, for example, be used in a power control algorithm by setting a power control indicator in response to a comparison between the signal power estimate and a predetermined threshold. Subsequently, the power control indicator is transmitted over a communication channel to another communication unit. The communication unit detects a power control indicator within a signal received from over the communication channel and adjusts a particular signal transmission power of a signal transmitter in response to the detected power control indicator.
    Type: Grant
    Filed: September 17, 1993
    Date of Patent: May 2, 1995
    Assignee: Motorola Inc.
    Inventor: Fuyun Ling
  • Patent number: 5408495
    Abstract: A base-site (304) combines baseband frequency hopping and fast-synthesizer hopping to produce an economical frequency hopping communication system (300). The base-site (304) combines the fast-synthesizer frequency hopping capability of transmitters (307-309) with baseband frequency hopping to produce a frequency hopping communication system (300) which serves the same number of subscribers served by transmitters (208-213) in a purely baseband hopping communication system (200), but with fewer transmitters (307-309). The implementation of frequency-selective cavities (312-317) having very low loss eliminates the need for wideband hybrid combiners (112-114), which in turn eliminates transmitted-signal power loss experienced in a purely fast-synthesizer frequency hopping communication system (100).
    Type: Grant
    Filed: May 7, 1993
    Date of Patent: April 18, 1995
    Assignee: Motorola, Inc.
    Inventors: Michael D. Kotzin, Stephen L. Spear
  • Patent number: 5396489
    Abstract: A method and apparatus are provided of transmultiplexing a plurality of signals between a plurality of signal terminals (17 or 29) and a plurality of selected radio frequency channels. The method includes the step of, and apparatus for, frequency translating and filtering the plurality signals between the plurality of selected channels and a polyphase discrete Fourier transform filter bank (16 or 21) within a comb filter (15 or 22). The method further includes the step of frequency division multiplexing the plurality of signals between the plurality of signal terminals and comb filter (15 or 22) within a polyphase discrete Fourier transform filter bank (16 or 21).
    Type: Grant
    Filed: October 26, 1992
    Date of Patent: March 7, 1995
    Assignee: Motorola Inc.
    Inventor: Robert M. Harrison
  • Patent number: 5390339
    Abstract: A radio communication system selects a serving transceiver for a remote unit by generating and using a center of mass location estimation. The radio communication system collects uplink and downlink signal characteristics, including impaired signals caused by co-channel interference, from a set of transceivers, including those adjacent to and non-adjacent to the candidate transceiver and remote unit, to aid in the estimation of the remote unit's location within the radio communication system. Using the uplink and downlink signal characteristics, the radio communication system determines weighted coordinates related to predetermined coordinates and the signal characteristics which are used to produce a first and second center of mass coordinate estimation. The radio communication system then selects the serving transceiver to be the transceiver whose predetermined coordinates are closest to the first and second center of mass coordinate estimation.
    Type: Grant
    Filed: October 23, 1991
    Date of Patent: February 14, 1995
    Assignee: Motorola Inc.
    Inventors: Eugene J. Bruckert, Stuart W. Thro
  • Patent number: 5381443
    Abstract: A cellular communication system hops both signalling channels and traffics channels in a common hopping sequence. To obtain system information from the frequency hopping signalling channel, a subscriber unit waits on a predetermined frequency, or carrier, until the frequency hopped signalling channel arrives at the predetermined frequency. Once arrived, the subscriber unit obtains synchronization information, and information related to the hopping sequence, from the signalling channel during the hop. The subscriber unit may then hop in tandem with the system, obtaining further system information in subsequent hops. The cellular communication system supports mobile assisted handoff (MAHO) by allowing a subscriber unit to measure signalling channel of neighboring cells in a similar manner, and using the measurements to assist in communication handoff from a source cell to a neighboring cell.
    Type: Grant
    Filed: October 2, 1992
    Date of Patent: January 10, 1995
    Assignee: Motorola Inc.
    Inventors: David E. Borth, John R. Haug, Phillip D. Rasky
  • Patent number: 5373506
    Abstract: A fixed base-site (115) periodically pages subscribers (120) in a paging area (100). To prolong the battery life of the subscribers (120), paging groups (520) are not sent to subscribers (120) as often when the paging load is small. Since the subscribers (120) support discontinuous receive, processing of the pages will not take place as frequently and thus a battery savings is realized. When the fixed base-site (115) receives more pages than can be supported without exceeding a predetermined delay, the fixed base-site (115) dynamically increases the frequency that paging groups (520) are transmitted to subscribers (120). When the paging load decreases, the fixed base-site (115) dynamically decreases the frequency that paging groups (520) are transmitted to subscribers (120) and again a savings in battery life is realized.
    Type: Grant
    Filed: July 9, 1993
    Date of Patent: December 13, 1994
    Assignee: Motorola Inc.
    Inventors: Daniel R. Tayloe, Eugene J. Bruckert
  • Patent number: 5369786
    Abstract: A radiotelephone system allows a subscriber unit (125) to transmit above a predetermined maximum power level. The maximum power level is set at a source base-station (130) and corresponds to the maximum power level a subscriber unit (125) can transmit at without subjecting neighboring target base-stations to interference. When the received signal strength indication (RSSI) of the subscriber unit (125) as measured by the source base-station (130) falls below a transfer threshold, the radiotelephone system determines if the subscriber unit (125) is in the best sector/cell. If the subscriber unit (125) is in the best sector/cell, the subscriber unit (125) is allowed to transmit at a power level above the predetermined maximum to maintain communication to the source base-station (130).
    Type: Grant
    Filed: May 1, 1991
    Date of Patent: November 29, 1994
    Assignee: Motorola, Inc.
    Inventor: Thomas G. Hulsebosch
  • Patent number: 5363404
    Abstract: A direct sequence code-division multiple access (DS CDMA) communication system schedules conveyance of blocks (400) of information such that the blocks arrive at a base-site (130) just-in-time for transmission during a discrete frame (301-305) of an air-interface. The DS CDMA communication system implements both circuit switching and packet switching approaches to provide trunking efficiencies while balancing between system loading constraints and time delay of blocks (400) during conveyance.
    Type: Grant
    Filed: July 13, 1993
    Date of Patent: November 8, 1994
    Assignee: Motorola Inc.
    Inventors: Michael D. Kotzin, Eugene J. Bruckert
  • Patent number: 5361067
    Abstract: A method and means are offered of providing of a calibrated output of a analog to digital converter. The method includes the steps of, and means for, generating a calibration table relating a calibrated output of the analog to digital converter and a detected output, and, upon determination of a need, providing, by reference to the calibration table, the calibrated output of the analog to digital converter corresponding to an detected output of the analog to digital converter.
    Type: Grant
    Filed: November 30, 1992
    Date of Patent: November 1, 1994
    Assignee: Motorola Inc.
    Inventor: Danny T. Pinckley
  • Patent number: 5329547
    Abstract: A method and apparatus is provided for encoding and decoding to facilitate coherent communication. In encoding, reference symbols are inserted into a stream of input data symbols to form a reference coded stream of input data symbols. Subsequently, the reference coded stream of input data symbols are prepared for transmission over a communication channel by spreading the reference coded stream of input data symbols with a spreading code prior to transmission over the communication channel. In decoding, a received communication signal is despread with a spreading code to derive a stream of reference samples and a stream of data samples. The channel response is estimated by utilizing the stream of reference samples. Finally, an estimated data symbol is detected from the stream of data samples by utilizing the estimated channel response.
    Type: Grant
    Filed: March 11, 1993
    Date of Patent: July 12, 1994
    Assignee: Motorola, Inc.
    Inventor: Fuyun Ling
  • Patent number: D349689
    Type: Grant
    Filed: May 28, 1993
    Date of Patent: August 16, 1994
    Assignee: Motorola, Inc.
    Inventors: Thomas G. Beaumont, Jon N. Diaz, David J. Clark, Michael K. Bullock