Patents Represented by Attorney, Agent or Law Firm Richard A. Sonnentag
  • Patent number: 5603087
    Abstract: Briefly described, the present invention is a circuit for detecting and indicating a level of interference on a high frequency angular modulated signal. This circuit includes a logarithmic amplifier for receiving high frequency angular modulated signals and for providing a logarithmic amplifier output in response thereto. Next, the angular modulated signals are detected to determine a level of associated FM modulation thereof. Finally, a processor, programmed to distinguish those high frequency spectrum components due to interference from those due to other sources, determines a carrier to interference ratio. Of note, when the level of FM modulation at the logarithmic amplifier input exceeds a predetermined threshold, however, the associated carrier to interference ratio is ignored.
    Type: Grant
    Filed: September 6, 1994
    Date of Patent: February 11, 1997
    Assignee: Motorola, Inc.
    Inventor: Edward C. Shultz
  • Patent number: 5594946
    Abstract: A communication system (100) employs a method (400) and apparatus (101, 113) for mitigating interference (119) produced by a communication unit (113) communicating with a serving base site (101) in the communication system (100). While the communication unit (113) is communicating with the serving base site (101), the communication unit (113) monitors (405) a downlink communication signal (118) transmitted by an alternate base site (105). The communication unit (113) then determines (407) an indicia of signal usability for the monitored downlink signal (118) and adjusts (421) a transmit power of the communication unit (113) based on the indicia of signal usability.
    Type: Grant
    Filed: February 28, 1995
    Date of Patent: January 14, 1997
    Assignee: Motorola, Inc.
    Inventors: Barry J. Menich, Akingbade R. Akinniyi
  • Patent number: 5590402
    Abstract: A dual-mode transmitter (100) adjusts a signal's deviation level when switched between a wideband mode and a narrowband mode of operation. The transmitter (100) automatically attenuates the deviation of the signal based on a ratio of the maximum deviation level for the wideband mode to the maximum deviation for the narrowband mode utilizing wideband/narrowband maximum deviation adjust circuitry (115). Because the attenuation based on the ratio of the maximum deviation levels is too large for a narrowband mode signal having average deviation, the signal is amplified based on a ratio of the average deviation level for the wideband mode to the average deviation for the narrowband mode utilizing wideband/narrowband average deviation adjust circuitry (103). Attenuation and amplification of the signal's deviation occur when the dual-mode transmitter (100) is operating in the narrowband mode.
    Type: Grant
    Filed: April 13, 1995
    Date of Patent: December 31, 1996
    Assignee: Motorola, Inc.
    Inventors: Randall J. Samson, Allan Budlong, Dan Huslig
  • Patent number: 5590418
    Abstract: A gain stabilization loop performs discrete time adjustments to the RF amplifier forward gain path of a closed-loop transmitter power control system based on a measurement of the gain in the control loop. The stabilization of the RF amplifier gain allows the transmitter's control loop to remain functional over varying gain Conditions which are prevalent within stages of the RF amplifier gain path. The effects of gain changes within the stages due to part-to-part variations. and temperature effects are minimized or eliminated by this gain trimming.
    Type: Grant
    Filed: September 30, 1993
    Date of Patent: December 31, 1996
    Assignee: Motorola, Inc.
    Inventors: Kevin J. Holoubek, Richard J. Keniuk, Paul R. Bontrager
  • Patent number: 5577043
    Abstract: A method and apparatus for controlling communications on a multipoint communication link includes a multipoint link (29) coupling plural slave stations (11-13) and a master (10) having a communications controller (35) controlling signaling broadcast to slave stations (11-13) via an encoder (36). Broadcast signals (201-205) each include a time slot marker or identifier associated with a slave station. Master (10) monitors via detector (32) for response signals (211-213) within a window period, and when detected waits until an end of transmission and generates the next broadcast signal with an incremented marker. Master (10) also functions to cycle through broadcast signals to all slave stations (11-13) at an adaptive rate, e.g., more frequently for active as compared with idle or inactive slave stations.
    Type: Grant
    Filed: September 21, 1994
    Date of Patent: November 19, 1996
    Assignee: Motorola, Inc.
    Inventors: Eileen J. Guo, Jeffrey W. Klingberg
  • Patent number: 5574984
    Abstract: After setting a base station to a transmit power level (12) which provides a signal at a subscriber unit having a target quality level, a fading characteristic of a communication channel between the subscriber unit and a base site is measured (13). The fading characteristic is then compared with a threshold value (14). The measuring (13) and comparing (14) are repeated until the fading characteristic crosses a threshold (15). Once the fading characteristic crosses the threshold for a receive Eb/No level that is representative of a e.g. static fading condition, the base transmit power that is transmitted to the subscriber is increased by a predetermined amount in anticipation of the need for an increased Eb/No for the case of a faded signal (61). The determination of the fading characteristic and threshold comparison may be performed at either the subscriber unit or the base station.
    Type: Grant
    Filed: December 13, 1994
    Date of Patent: November 12, 1996
    Assignee: Motorola, Inc.
    Inventors: John D. Reed, Walter J. Rozanski, Jr.
  • Patent number: 5574466
    Abstract: A method for wireless communication system planning includes, in a first embodiment, determining an image tree (500), based on a transmitter location (401) and the reflective (415) and diffractive (425) surfaces within a coverage region, and limiting the image tree to exclude branching for higher order images requiring more than a predetermined number of reflections and/or diffractions, or potential child images corresponding to surfaces not within the scope of the parent image (530, 560). Based on the image tree and propagation path back-tracing (620) a received signal quality measure (e.g., power) is determined for each transmit location. By comparing the different received signal powers an optimal receiver unit location is determined. Further, by back-tracing for further antenna locations/combinations, and comparing for diversity effects (864, 865), overall coverage qualities can be determined for each antenna combination and compared to yield optimal base diversity antenna locations (867).
    Type: Grant
    Filed: May 30, 1995
    Date of Patent: November 12, 1996
    Assignee: Motorola, Inc.
    Inventors: John D. Reed, Yuqiang Tang
  • Patent number: 5570343
    Abstract: In order to mitigate problems caused by total or partial failure of a number of sectorised radio channel unit transceivers (RCU) in a base station of a particular cell (16) of a radio communications system, base stations (26, 32) in adjacent cells (14, 20) increase the power transmitted from RCUs controlling sectors adjacent to that particular cell 16, thereby filling the gap in coverage left by the failure of that cell (16).
    Type: Grant
    Filed: July 27, 1994
    Date of Patent: October 29, 1996
    Assignee: Motorola, Inc.
    Inventors: Peter W. D. Bishop, Ian M. Bartlett
  • Patent number: 5568349
    Abstract: A relay device (103) having a coil (144) and a set of contacts (146, 147) employs an apparatus (100) and method (200) for drawing current through the coil (144) to close, and maintain closure of, the set of contacts (146, 147). A first terminal of the coil (144) is coupled to a power supply (101) and a second terminal of the coil is coupled to a holding circuit (108, 115, 126) that establishes a first current through the coil (144). The second terminal of the coil (144) is also coupled to a closing circuit (112) that establishes a second current through the coil (144), wherein the first current and the second current together are at least sufficient to close the set of contacts (146, 147) and the first current is sufficient to maintain closure of the closed set of contacts (146, 147). A control circuit (118, 128) is coupled to the closing circuit (112) and the holding circuit (108, 115, 126) to remove the second current after the set contacts (146, 147) are closed.
    Type: Grant
    Filed: April 4, 1995
    Date of Patent: October 22, 1996
    Assignee: Motorola, Inc.
    Inventor: Rolf E. Kowalewski
  • Patent number: 5555447
    Abstract: A communication system mitigates speech loss due to a delay (D) incurred during communication channel set-up and also accounts for the delay (D). The communication system time-compresses certain speech spoken by a user and buffers this time-compressed speech in a FIFO (827) at least until the communication channel set-up has been completed. Upon channel set-up, the communication system begins transmission of the stored time-compressed speech and transitions to transmission of normal spoken speech when the FIFO (827) storing the time-compressed speech is substantially empty.
    Type: Grant
    Filed: May 14, 1993
    Date of Patent: September 10, 1996
    Assignee: Motorola, Inc.
    Inventors: Michael D. Kotzin, Gary W. Grube
  • Patent number: 5546429
    Abstract: A radio communication unit for a digital communication system is provided in which an input information signal is protected from transmission errors by forward error correction encoding the information signal. In addition, the communication unit enhances subsequent processing of a transmitted form of the information signal by a hard-limiting receiver by inserting a predetermined synchronization sequence into the information signal. Further, a corresponding radio communication unit is provided which includes a hard limiting mechanism for removing the magnitude of each sample in a group of data samples of a signal received from over a radio communication channel. In addition, weighting coefficients of the hard-limited group of data samples for maximum likelihood decoding and diversity combining are generated by comparing the hard-limited group of data samples to a known predetermined synchronization sequence.
    Type: Grant
    Filed: November 9, 1992
    Date of Patent: August 13, 1996
    Assignee: Motorola, Inc.
    Inventors: Gregory M. Chiasson, Phillip D. Rasky, Kevin L. Baum
  • Patent number: 5521938
    Abstract: An efficient apparatus for performing frequency conversion from a final IF frequency to a baseband frequency is described. A counter (401) generates two logical signals G1 (402) and G2 (403) which are passed to an exclusive-OR gate (404) and a multiplexer (406). When a control signal (411) is deasserted, multiplexer (406) passes signal G1 to I1 and signal G2 to I2; when control signal (411) is asserted, multiplexer (406) passes binary signal G1 to I2 (410) and signal G2 to I1 (407). Similarly, multiplexer (405) swaps its input real and imaginary samples when the output of exclusive-OR gate (404) is asserted; otherwise, it performs no operation on its input samples. Signals I1 (407) and I2 (410) are used to control arithmetic inverters (408) and (409) respectively. When the controlling signal for either inverter is asserted, the inverter performs arithmetic inversion, otherwise it performs no operation.
    Type: Grant
    Filed: July 1, 1994
    Date of Patent: May 28, 1996
    Assignee: Motorola, Inc.
    Inventors: Kenneth A. Stewart, Robert T. Love
  • Patent number: 5517675
    Abstract: Transmission of candidate-sector signalling channels are synchronized to facilitate mobile-assisted handoff (MAHO) measurements by a mobile (125). Transmitters in candidate sectors each transmit their signalling channel at distinct frequencies and at predetermined intervals. The transmission of each signalling channel by each candidate sector transmitter is synchronized to provide a known reference to the mobile (125). When instructed, the mobile (125) need only to perform MAHO measurements at the predetermined intervals in the order and at the frequency instructed.
    Type: Grant
    Filed: February 13, 1995
    Date of Patent: May 14, 1996
    Assignee: Motorola, Inc.
    Inventors: James M. O'Connor, Eric R. Schorman, John D. Reed, Kamyar Rohani
  • Patent number: 5515396
    Abstract: A communication system utilizes multiple spreading codes to transmit high data rate information. The system codes high data rate user information (201) and partitions the coded information (202) into blocks comprised of two bits, B1 and B2. Based on the representation of bits B1 and B2, the system chooses one of a possible four spreading codes (W.sub.1 and W.sub.2 and their phase reversals W.sub.1 ' and W.sub.2 ') to be utilized for transmission. Once received, the transmitted signal is input into correlators (306, 309) specific to each spreading code W1 and W2, and the maximum absolute value output from the correlators (306, 309) is determined. From this determination, the transmitted spreading code W.sub.1, W.sub.2, W.sub.1 ' or W.sub.2 ' is determined. The use of multiple spreading codes allows the for the transmission of high data rate information without altering the wireless air interface of the communication system.
    Type: Grant
    Filed: February 25, 1994
    Date of Patent: May 7, 1996
    Assignee: Motorola, Inc.
    Inventor: Michael Dalekotzin
  • Patent number: 5506863
    Abstract: A communication unit for use in a communication system is provided which includes a hopping mechanism which hops communication frames over a plurality of carrier frequencies according to a predetermined hopping pattern. At least one of the communication frames preferably includes a synchronization channel time slot having data bits from which the predetermined hopping pattern may be derived. In addition, a communication unit is provided which includes a signal acquisition mechanism for initially acquiring a predetermined hopping pattern that specifies the sequence over which hop frames are hopped over a plurality of carrier frequencies. Also, this communication unit includes a hopping mechanism for hopping receiving frequency according to the predetermined hopping pattern such that a control channel may be detected. In an alternative embodiment, either communication unit may derive the predetermined hopping pattern from detected global position satellite information.
    Type: Grant
    Filed: August 25, 1993
    Date of Patent: April 9, 1996
    Assignee: Motorola, Inc.
    Inventors: Reuven Meidan, Duane C. Rabe, Michael D. Kotzin
  • Patent number: 5506867
    Abstract: A radio frequency backbone communication system is offered for exchanging, a plurality of communicated signals between a central site (205) and a plurality of communication units (16-18) through a plurality of remote base sites (60-66). The system includes at least one mobile function transceiver (201-204) located at the central site (205), transceiving a communicated signal of the plurality of communicated signals on a shared communication resource of a base site of the plurality of base sites (60-66) and, means for synchronizing a transceiver at the base site to the communicated signal of the at least one mobile function transceiver (201-204).
    Type: Grant
    Filed: December 28, 1994
    Date of Patent: April 9, 1996
    Assignee: Motorola, Inc.
    Inventors: Michael D. Kotzin, Valy Lev, Stephen L. Spear
  • Patent number: 5504457
    Abstract: This invention relates to a pulsed power amplifier 100 for amplifying radio frequency signals. The pulsed power amplifier comprises control means 124, 126, 102 for generating control signals to control the amplifier output power so as to provide an output power pulse having rising and falling transitional phases, and means 112, 114, 117, 118, 122, 132, 134, 137, 138, 142 for generating a subsidiary pulse signal to be applied to the control means in order to adjust a transitional phase of the output power pulse. The generation of the subsidiary pulse may depend on a measured parameter of a previous output power pulse, such as the time taken for a preceding output power pulse to reach a predetermined output power level. Alternatively, the generation of the subsidiary pulse may depend on a parameter of the present output power pulse. In both cases the generating means can control the magnitude of the subsidiary pulse in response to the parameter.
    Type: Grant
    Filed: March 8, 1993
    Date of Patent: April 2, 1996
    Assignee: Motorola, Inc.
    Inventor: Ole Jensen
  • Patent number: 5502752
    Abstract: An apparatus and method for clock rate matching in independent networks is disclosed. The apparatus accepts data from a modem (126) into a buffer (400) and determines the difference between the rate of the data entering the buffer (400) at the modem clock rate to the rate of data exiting the buffer (400) at the clock rate used by the apparatus. Depending on the rate difference, the apparatus either speeds up or slows down the data rate accordingly.
    Type: Grant
    Filed: April 20, 1993
    Date of Patent: March 26, 1996
    Assignee: Motorola, Inc.
    Inventors: Nimrod Averbuch, Steven V. Schatz
  • Patent number: 5495505
    Abstract: A direct digital frequency synthesizer increases the frequency resolution of the analog output signal by using fractionalization techniques. The best integer value I.sub.FR of a digital signal is determined and the next integer value I.sub.FR +1 of a digital signal is used to determine a weighted fractionalized value of the digital signal. The fractionalized value of the digital signal is used to synthesize the analog output signal having increased frequency resolution. In addition, IFR and IFR+1 are optimally distributed during the weighting process to ensure a minimum cumulative phase error.
    Type: Grant
    Filed: December 20, 1990
    Date of Patent: February 27, 1996
    Assignee: Motorola, Inc.
    Inventor: Thomas J. Kundmann
  • Patent number: D369170
    Type: Grant
    Filed: November 14, 1994
    Date of Patent: April 23, 1996
    Assignee: Motorola, Inc.
    Inventors: Thomas G. Beaumont, Alfred D. Meyers