Patents Assigned to Ericsson, Inc.
  • Patent number: 6931050
    Abstract: Digital receivers and receiving methods scale for relative strengths of traffic and pilot channels during soft handoff. In particular, spread spectrum signals are processed from traffic channels and pilot channels by receiving data samples from traffic channels and pilot channels. Detection statistics are obtained from the received data samples that correspond to information symbols while accounting for the relative strengths of the traffic channels and the pilot channels. The detection statistics are preferably obtained by performing Rake combining while accounting for the relative strengths of the traffic channels and the pilot channels.
    Type: Grant
    Filed: December 3, 1998
    Date of Patent: August 16, 2005
    Assignee: Ericsson Inc.
    Inventor: Gregory E. Bottomley
  • Patent number: 6925059
    Abstract: Method and apparatus for distributing traffic in a wireless packet data network. A capacity flag which is sent on each RF data channel within a cell in a wireless packet data network is toggled between an asserted and an unasserted state according to the period of a timer. Transceiver terminals will only register for a channel while that channel's capacity flag is unasserted; therefore, transceiver terminals register with the various RF channels in a cell in a distributed fashion over time. The invention can be implemented by a computer program product or logic, or a combination of the two installed at the base station for a cell within a wireless data network such as a CDPD network.
    Type: Grant
    Filed: May 9, 2001
    Date of Patent: August 2, 2005
    Assignee: Ericsson, Inc.
    Inventors: Evin Feli, Leonard Lee, Dayong Chen
  • Patent number: 6925072
    Abstract: A system and method for sending control information between a control unit and at least one of a plurality of cascaded units (CU) connected via a time-multiplexed communications link comprises generating an information message of a predetermined length at a message generator including a CU identifier value and control information, where the CU identifier value corresponds to a designated CU. The information message is sent to a current CU using the time multiplexed communications link. The information message is processed at the current CU, including determining whether the CU identifier value matches the identity of the current CU where the information message is a downlink message.
    Type: Grant
    Filed: August 3, 2000
    Date of Patent: August 2, 2005
    Assignee: Ericsson Inc.
    Inventor: Ossi Ilari Grohn
  • Patent number: 6925127
    Abstract: A receiver decodes quantized and unquantized wanted data symbols from received signal samples. The receiver comprises a control adapted to process a group of currently received signal samples to determine a corresponding current set of unquantized wanted data symbols and an interfering waveform representative of a sum of other unwanted data symbols by subtracting an amount of a previously decoded set of quantized wanted symbols and a previously determined interfering waveform. A quantizer quantizes the determined current set of unquantized wanted symbols to obtain corresponding quantized symbols.
    Type: Grant
    Filed: October 6, 2000
    Date of Patent: August 2, 2005
    Assignee: Ericsson Inc.
    Inventor: Paul W. Dent
  • Patent number: 6922434
    Abstract: Methods of recovering information encoded in a spread spectrum signal transmitted according to a spreading sequence in a communications medium are provided in which a spread spectrum signal is received from the communications medium and correlated with a spreading sequence to produce a plurality of time-offset correlations. Some of these time-offset correlations may be designed to cancel out known interfering signals. A subset of the plurality of time-offsets may then be selected, and corresponding traffic correlations may then be combined using a weighted combination to estimate information encoded in the transmitted spread spectrum signal. Receivers for implementing these methods are also provided.
    Type: Grant
    Filed: April 30, 2001
    Date of Patent: July 26, 2005
    Assignee: Ericsson Inc.
    Inventors: Yi-Pin Eric Wang, Gregory E. Bottomley, Kenzo Urabe
  • Patent number: 6920315
    Abstract: A multiple antenna mobile communication device, such as a cellular telephone, having multiple radios and multiple antennas located in close proximity to each other uses a parallel tuning circuit to optimize the isolation between the antennas. The parallel tuning circuit can include multiple impedance matching circuits to match the impedance in multiple frequency bands or isolating antennas.
    Type: Grant
    Filed: March 22, 2000
    Date of Patent: July 19, 2005
    Assignee: Ericsson Inc.
    Inventors: Bruce Emerson Wilcox, Mark Gordon Douglas
  • Patent number: 6920324
    Abstract: Methods, receivers, transmitters, and systems are provided for performing a soft hand-over of a mobile terminal between base station transceivers that communicate using different communication channels. A mobile terminal may be configured to receive and demodulate signals on a plurality of different communication channels concurrently and to modulate and transmit signals on a plurality of different communication channels concurrently. This allows, for example, multiple communication connections to be concurrently established between the mobile terminal and a plurality of different base station transceivers that use the different communication channels to communicate.
    Type: Grant
    Filed: April 10, 2001
    Date of Patent: July 19, 2005
    Assignee: Ericsson Inc.
    Inventors: Roozbeh Atarius, Murali Narasimha, Wail Refai, Stuart B. Sanders
  • Patent number: 6920120
    Abstract: A system and method of scheduling radio resources in a packet-switched wireless communications network. A plurality of data packets from a plurality of users are placed in a First-In-First-Out (FIFO) queue and are sequentially selected and analyzed for transmission. If a selected packet has an instantaneous radio channel quality (C/I) greater than a historical channel quality value, the packet is transmitted. If the instantaneous C/I is not greater than the historical value, it is determined whether the selected packet has been held for longer than a threshold time period. If so, the selected packet is transmitted. If neither condition is met, the selected packet is temporarily held in its position in the queue while analyzing the next packet for transmission. If no packets qualify for transmission, the packet in the first position is transmitted. After each transmission, the analysis starts again at the head of the queue.
    Type: Grant
    Filed: August 22, 2002
    Date of Patent: July 19, 2005
    Assignee: Ericsson Inc.
    Inventors: Dongjie Huang, Jianxu Shi
  • Patent number: 6917629
    Abstract: An improved system and method for rate detection of transmitted signals is disclosed for use in a IS-95 CDMA downlink. For each speech frame, one of four possible bit rates is used to encode the frame according to the standard. The present invention describes a receiver and various processes that are able to detect which rate was sent without the aid of flag bits or other mode indication information. According to various embodiments of the invention different rate detection processes which can exploit additional code information, such as CRC checks and convolutional coding, are disclosed.
    Type: Grant
    Filed: September 11, 1998
    Date of Patent: July 12, 2005
    Assignee: Ericsson Inc.
    Inventors: Rajaram Ramésh, Gregory E. Bottomley
  • Patent number: 6914885
    Abstract: A demodulated data stream is selected by concurrently demodulating radio signals to provide a first data stream and a second data stream with the first data stream. A first error level associated with the first data stream is determined. A second error level associated with the second data stream is also determined. The data stream having the better error level can be selected for further processing. Related wireless radio receivers are also disclosed.
    Type: Grant
    Filed: May 7, 2001
    Date of Patent: July 5, 2005
    Assignee: Ericsson Inc.
    Inventors: Prasada Rao, Robert A. Zak
  • Patent number: 6909757
    Abstract: Embodiments of methods, transmitters, and computer program products are provided for transmitting a signal by adjusting a delay between an amplitude component of the signal and a phase component of the signal based on the transmission power. Error vector magnitude and adjacent channel power ratio are two common criteria used in evaluating transmitter performance. By adjusting the delay between the amplitude component of the transmitted signal and the phase component of the transmitted signal, the error vector magnitude and/or the adjacent channel power ratio may be reduced. The particular delay value that provides the best error vector magnitude performance and/or adjacent channel power ratio performance may differ based on the transmission power level. Therefore, the delay value is adjusted based on the transmission power.
    Type: Grant
    Filed: May 14, 2001
    Date of Patent: June 21, 2005
    Assignee: Ericsson Inc.
    Inventors: Scott R. Justice, Erik L. Bengtsson, David R. Pehlke
  • Patent number: 6909719
    Abstract: The present invention provides a system, method and apparatus for providing multiple quality of service classes to subscribers in a network by determining a subscriber's quality of service information by using a database containing quality of service information for each subscriber that has subscribed to one of the multiple quality of service classes, and storing the subscriber's quality of service information in a visitor location register where the subscriber is currently registered.
    Type: Grant
    Filed: December 22, 1999
    Date of Patent: June 21, 2005
    Assignee: Ericsson Inc.
    Inventors: Stefan Petersson, Vladimir Alperovich, Shri Balachandran, Lee Davidson, Nauman Shakil, Martin Reichelt, Johan Sannero
  • Patent number: 6907242
    Abstract: A system and method for providing local service to non-local subscribers in a telecommunications network. The systems and methods employ mapping of a subscriber IMSI with a unique local identifier for use by the local system for locally originating and terminating calls.
    Type: Grant
    Filed: October 2, 2001
    Date of Patent: June 14, 2005
    Assignee: Ericsson Inc.
    Inventor: Kaushal Thakker
  • Patent number: 6904150
    Abstract: A method and system for encrypting and decrypting a message. A message is created by appending an error detection code to an information block. The binary value of the resulting message is then compared to the sender's encryption modulus. If the binary value of the message is greater than or equal to the sender's encryption modulus, at least one bit of the error detection code is altered to reduce the binary value of the message below the sender's encryption modulus. The potentially modified message is then encrypted once using the sender's private key to generate a once encrypted message referred to herein as the signed message. The signed message is then encrypted using the recipient's public key to produce a doubly encrypted bitstring. The recipient deciphers and decodes the doubly encrypted bitstring.
    Type: Grant
    Filed: October 25, 2000
    Date of Patent: June 7, 2005
    Assignee: Ericsson Inc.
    Inventor: Paul W. Dent
  • Patent number: 6898431
    Abstract: In a sectored cell of a cellular communication network, channels are dynamically reassigned from a first sector in the cell to a second sector in the same cell when the loading in the first sector reaches a predetermined threshold. The channels allocated to the cell are further subdivided into subgroups and assigned initially to respective sectors in the cell. During normal operation, the channels in each sector are allocated to users in that sector in the usual manner. When the number of channels allocated in a first sector of the cell reaches a predetermined threshold, the base station controller polls the remaining sectors for unused channels. If an unused channel is found, that channel may be reassigned to the first sector. In one embodiment, the base station controller polls the controller in the nearest co-channel cells before reassigning the channel to prevent co-channel interference.
    Type: Grant
    Filed: May 24, 1999
    Date of Patent: May 24, 2005
    Assignee: Ericsson Inc.
    Inventor: James Calvin Peele
  • Patent number: 6895428
    Abstract: A method of storing an e-mail address within an Abbreviated Dialing Number (ADN) record of a Subscriber Identity Module (SIM) card is provided. The ADN record typically includes a plurality of fields having personal contact information relating to a contact stored in the ADN record. The inventive method includes the steps of allocating a first number of bytes of memory space to a first field in the ADN record, storing an e-mail address of a contact in the first field in the ADN record, and setting a flag in a second field in the ADN record indicating a presence of a e-mail address in the first field in the ADN record.
    Type: Grant
    Filed: January 21, 2001
    Date of Patent: May 17, 2005
    Assignee: Ericsson Inc.
    Inventor: Scott G. Hicks
  • Patent number: 6895247
    Abstract: A method of obtaining optimum RF performance for a slave base station when co-siting a master base station with said slave base station involves calculating operating characteristics of the slave base station that is sharing an antenna assembly with the master base station. The third order intercept (IP3) and the noise figure (NF) characteristics of the slave base station are calculated and plotted versus a range of upfront gain values. The plots are studied and compared against vendor specifications and standalone performance characteristics. A desired upfront gain value is then selected to achieve a particular IP3 and NF characteristic for the slave base station. Upon selection, the upfront gain supplied to the slave base station is adjusted via an attenuator placed in-line before the slave base station to match the desired upfront gain.
    Type: Grant
    Filed: November 1, 2001
    Date of Patent: May 17, 2005
    Assignee: Ericsson, Inc.
    Inventor: Ayman Mostafa
  • Patent number: 6891883
    Abstract: A direct sequence spread spectrum receiver for operating in a multipath fading channel comprises a rake receiver having plural rake fingers. Each rake finger demodulates a received signal from one of plural channel paths. The output of the plural rake fingers are combined. Each rake finger utilizes a select assigned delay to synchronize to a delay of the one channel path. A searcher periodically performs a channel search on the received signal to detect new delays of strongest paths in the channel. Plural trackers, one for each channel path, adjust the select assigned delays between searches performed by the searcher. A delay controller is operatively coupled to the searcher and the trackers. The delay controller compares new delays of the strongest paths from the searcher to the select assigned delays and reassigns one of the select assigned delays with one of the new delays only if the new delay differs from the one select assigned delay more than a predetermined threshold.
    Type: Grant
    Filed: February 13, 2003
    Date of Patent: May 10, 2005
    Assignee: Ericsson Inc.
    Inventors: Essam Sourour, Gregory E. Bottomley, Rajaram Ramesh
  • Patent number: 6889034
    Abstract: Multiple radio channel frequency signals that are modulated with respective information modulation are transmitted from a common antenna at multiple radio frequencies. Multiple modulators are provided, a respective one of which corresponds to a respective one of the radio channel frequencies. Each modulator generates at least one constant amplitude, phase modulated drive signal at the corresponding radio channel frequency from the respective information modulation, such that the at least one constant amplitude, phase modulated drive signal corresponds to the information modulation for the corresponding radio frequency. At least one saturated power amplifier is provided for each of the at least one constant amplitude, phase modulated drive signals. A respective saturated power amplifier is responsive to the corresponding constant amplitude, phase modulated drive signal, to produce a corresponding amplified output signal at an output thereof.
    Type: Grant
    Filed: December 14, 1999
    Date of Patent: May 3, 2005
    Assignee: Ericsson Inc.
    Inventor: Paul Wilkinson Dent
  • Patent number: 6885869
    Abstract: A mobile terminal includes a primary transceiver to communicate with a mobile communication network and a secondary transceiver to communicate with a base unit of a cordless telephone system. When the mobile terminal is out of range of the base unit, it searches or listens for the base unit at a predetermined searching or listening frequency. The searching or listening frequency is dependent upon the distance of the mobile terminal from the base unit. A threshold is also established beyond which the mobile terminal may discontinue searching or listening for the base unit to conserve battery power or, alternatively, set the searching or listening frequency to a minimum value.
    Type: Grant
    Filed: January 26, 2001
    Date of Patent: April 26, 2005
    Assignee: Ericsson Inc.
    Inventor: Alex Krister Raith