Patents by Inventor Ulf Skarby

Ulf Skarby 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: 9048931
    Abstract: A filter arrangement comprises a first terminal that handles duplex radio antenna feeder signals for at least two transceiver modules, a second terminal that handles at least duplex signals for a first transceiver module, a third terminal that outputs a first multi carrier power amplifier system input signal, the input signal representing a transmit signal from the first transceiver module, and a fourth terminal that receives a multi carrier power amplifier system output signal. The output signal includes an amplified representation of the transmit signals from the two transceiver modules. The first and second terminals are connected via first a single filter, the second and third terminals are connected via a second single filter, and the fourth and first terminals are connected via a third single filter.
    Type: Grant
    Filed: April 1, 2013
    Date of Patent: June 2, 2015
    Assignee: Unwired Planet, LLC
    Inventors: Bo Berglund, Ulf Skarby
  • Patent number: 8340692
    Abstract: In one aspect, the invention provides apparatuses and methods for determining the location of a wireless user equipment (UE). Advantageously, the location may be determined by combining location estimates from a plurality of wireless network operators to increase accuracy.
    Type: Grant
    Filed: July 9, 2009
    Date of Patent: December 25, 2012
    Assignee: Telefonaktiebolaget L M Ericsson (publ)
    Inventors: Ulf Skarby, Mans Persson
  • Patent number: 8064958
    Abstract: A method, device and system for reducing the number of feeders (2, 3) between a radio base station (1) and an antenna diversity arrangement (10, 11, 12, 13) at which RF signals of the same frequency are received. In a tower mounted amplifier (45) individual RF signals from some or all of the antennas are frequency converted into intermediate frequency (IF) signals on mutually different intermediate frequencies which are combined and forwarded to the radio base station on a reduced number of feeders. In the radio base station the combined signal is split into individual signals amongst which the IF signals are frequency transformed to a signal suitable for diversity processing.
    Type: Grant
    Filed: March 11, 2004
    Date of Patent: November 22, 2011
    Assignee: Telefonaktiebolaget LM Ericsson (publ)
    Inventors: Ulf Skarby, Bo Hedberg
  • Patent number: 7944995
    Abstract: A variable bandwidth receiver uses allocated bandwidth more efficiently and ensures that blocking signals do not overload receiver components. The receiver includes multiple branches for receiving a first bandwidth signal. Each receiver branch has a filter for passing signals in a frequency band corresponding to a second bandwidth less that the first bandwidth and an analog-to-digital converter for converting the baseband signal into a digital signal. A controller digitally combines the digital signals from two or more of the receiver branches to produce a received signal having a bandwidth substantially wider than the first bandwidth. Because combining is done after analog-to-digital conversion in the digital domain, the controller can combine the digital signals from two or more of the receiver branches having adjacent corresponding frequency bands without the normal guard band separating them.
    Type: Grant
    Filed: October 11, 2006
    Date of Patent: May 17, 2011
    Assignee: Telefonaktiebolaget LM Ericsson (publ)
    Inventors: Ulf Skarby, Karl Gösta Sahlman
  • Patent number: 7797013
    Abstract: Radio transmissions to multiple radio terminals are improved using scheduled backoff of a multi-signal power amplifier. A radio channel quality associated with each of the radio terminals is determined. First signals for first radio terminals associated with a better channel quality are amplified by a power amplifier during a first time period resulting in a first composite output signal. Second signals for second radio terminals associated with a lower channel quality are amplified by the power amplifier during a second time period resulting in a second composite output signal. Transmission during the first time period occurs at a first power level, e.g., mean power, that is associated with a lower probability of clipping the first composite output signal. During the second time period, the second composite signal is transmitted at a second power level, e.g., mean power, higher than the first power level which improves reception at the second terminals.
    Type: Grant
    Filed: February 28, 2007
    Date of Patent: September 14, 2010
    Assignee: Telefonaktiebolaget LM Ericsson (publ)
    Inventors: Ulf Skarby, Karl-Gosta Sahlman
  • Publication number: 20100151908
    Abstract: A base station includes multiple sector antenna units. Each sector antenna unit has an antenna for receiving a carrier signal associated with an antenna frequency in an available frequency band. The base station is converted between a multiple sector base station configuration and a multi-sector, omni-base station configuration. In a diversity base station implementation, each sector antenna unit receives a diversity signal from a first sector, and the second diversity antenna unit receives a diversity signal from a second different sector. If one sector antenna unit does not perform properly so that one of the sector diversity signals is lost or corrupted, the other sector diversity signal is still useable. The base station may be reconfigured to power-down at least some part of the transmit side without having to power-down some or all of the receive side.
    Type: Application
    Filed: February 18, 2010
    Publication date: June 17, 2010
    Applicant: Telefonaktiebolaget LM Ericsson (publ)
    Inventors: Ulf Skarby, Rune Johansson, Sven Patrik Lindell, Dan Anders Lindqvist
  • Publication number: 20080287163
    Abstract: A base station includes multiple sector antenna units. Each sector antenna unit has an antenna for receiving a carrier signal associated with an antenna frequency in an available frequency band. The base station is converted between a multiple sector base station configuration and a multi-sector, omni-base station configuration. In a diversity base station implementation, each sector antenna unit receives a diversity signal from a first sector, and the second diversity antenna unit receives a diversity signal from a second different sector. If one sector antenna unit does not perform properly so that one of the sector diversity signals is lost or corrupted, the other sector diversity signal is still useable. The base station may be reconfigured to power-down at least some part of the transmit side without having to power-down some or all of the receive side.
    Type: Application
    Filed: May 17, 2007
    Publication date: November 20, 2008
    Applicant: Telefonaktiebolaget LM Ericsson (Publ),
    Inventors: Ulf Skarby, Rune Johansson, Sven Patrik Lindell, Dan Anders Lindqvist
  • Publication number: 20080267097
    Abstract: A filter arrangement (EFM) comprises a first terminal (T1) arranged for handling duplex radio antenna feeder signals for at least two transceiver modules (10, 20), a second terminal (T2) arranged for handling at least duplex signals for a first transceiver module (10), a third terminal (T3) arranged for outputting a first multi carrier power amplifier system input signal, said input signal representing a transmit signal from said first transceiver module (10), a fourth terminal (T4) arranged for receiving a multi carrier power amplifier system output signal, said output signal comprising an amplified representation of the transmit signals from said at least two transceiver modules, and wherein said first and said second terminal (T1, T2) are connected via first single filter means (RX), said second and said third terminal (T2, T3) are connected via second single filter means (TX1), said fourth and said first terminal (T4, T1) are connected via third single filter means (TX2).
    Type: Application
    Filed: June 17, 2005
    Publication date: October 30, 2008
    Inventors: Bo Berglund, Ulf Skarby
  • Publication number: 20080207143
    Abstract: Radio transmissions to multiple radio terminals are improved using scheduled backoff of a multi-signal power amplifier. A radio channel quality associated with each of the radio terminals is determined. First signals for first radio terminals associated with a better channel quality are amplified by a power amplifier during a first time period resulting in a first composite output signal. Second signals for second radio terminals associated with a lower channel quality are amplified by the power amplifier during a second time period resulting in a second composite output signal. Transmission during the first time period occurs at a first power level, e.g., mean power, that is associated with a lower probability of clipping the first composite output signal. During the second time period, the second composite signal is transmitted at a second power level, e.g., mean power, higher than the first power level which improves reception at the second terminals.
    Type: Application
    Filed: February 28, 2007
    Publication date: August 28, 2008
    Applicant: Telefonaktiebolaget LM Ericsson (publ)
    Inventors: Ulf Skarby, Karl-Gosta Sahlman
  • Publication number: 20080119197
    Abstract: The invention relates to an antenna diversity arrangement and a radio base station in a frequency divided mobile cellular system with sectorized cells. Space diversity or polarization diversity is provided by providing at least two branches. In accordance with the invention an operator frequency band is divided into a plurality of bands for transmitting and receiving. All sectors are branch wise combined in a respective tower mounted amplifier. TX signals within the TX bands belonging to a TMA are diplexed and simultaneously transmitted on the sectors. RF signals received on one branch of a sector are combined with RF signals received on the corresponding sector in the other branches. The RX signals so combined are fed to the radio base station on a single feeder together with the TX signals fed in the opposite direction from transceivers of the base station to the same TMA. A sector may be assigned two or more TX frequencies. Frequency hopping within each TX band may optionally be provided (synth hopping).
    Type: Application
    Filed: June 15, 2004
    Publication date: May 22, 2008
    Inventor: Ulf Skarby
  • Publication number: 20070191064
    Abstract: A method, device and system for reducing the number of feeders (2, 3) between a radio base station (1) and an antenna diversity arrangement (10, 11, 12, 13) at which RF signals of the same frequency are received. In a tower mounted amplifier (45) individual RF signals from some or all of the antennas are frequency converted into intermediate frequency (IF) signals on mutually different intermediate frequencies which are combined and forwarded to the radio base station on a reduced number of feeders. In the radio base station the combined signal is split into individual signals amongst which the IF signals are frequency transformed to a signal suitable for diversity processing.
    Type: Application
    Filed: March 11, 2004
    Publication date: August 16, 2007
    Applicant: Telefonaktiebolaget LM Ericsson (publ)
    Inventors: Ulf Skarby, Bo Hedberg
  • Publication number: 20070173288
    Abstract: An omni-radio base station with multiple sector antenna units uses frequency division of sector signals to achieve increased coverage or capacity at reduced cost. Each sector antenna unit has an antenna for receiving a carrier signal associated with an antenna frequency in an available frequency band. At least one of the antenna units has an associated frequency converter that converts the carrier signal received by that antenna unit from the antenna frequency to a different respective frequency. Even though each sector receives the same carrier signal, an output carrier signal associated with each sector is at a different frequency band. A combiner combines the antenna unit carrier signals at different frequencies to create a composite signal for communication to the omni-radio base station.
    Type: Application
    Filed: December 1, 2006
    Publication date: July 26, 2007
    Applicant: Telefonaktiebolaget LM Ericsson (publ)
    Inventors: Ulf Skarby, Donald Staudte
  • Publication number: 20070110177
    Abstract: Data is transmitted during a transmission time interval using an available frequency bandwidth. Blocks of data to be transmitted at different power levels are identified. Multiple portions of the data blocks are distributed for transmission at different frequencies so that data blocks with higher power levels are distributed more toward the center of the determined frequency bandwidth than data blocks with lower power levels. The distributing of data block portions reduces the power of intermodulation products occurring outside the determined frequency bandwidth caused by radio frequency signals carrying the distributed data block portions fed through a non-linear power amplifier. It also reduces peaks in the power of the intermodulation products.
    Type: Application
    Filed: November 8, 2006
    Publication date: May 17, 2007
    Applicant: Telefonaktiebolaget LM Ericsson
    Inventors: Mats Molander, Karl Sahlman, Ulf Skarby
  • Publication number: 20070110198
    Abstract: A variable bandwidth receiver uses allocated bandwidth more efficiently and ensures that blocking signals do not overload receiver components. The receiver includes multiple branches for receiving a first bandwidth signal. Each receiver branch has a filter for passing signals in a frequency band corresponding to a second bandwidth less that the first bandwidth and an analog-to-digital converter for converting the baseband signal into a digital signal. A controller digitally combines the digital signals from two or more of the receiver branches to produce a received signal having a bandwidth substantially wider than the first bandwidth. Because combining is done after analog-to-digital conversion in the digital domain, the controller can combine the digital signals from two or more of the receiver branches having adjacent corresponding frequency bands without the normal guard band separating them.
    Type: Application
    Filed: October 11, 2006
    Publication date: May 17, 2007
    Applicant: Telefonaktiebolaget LM Ericsson (publ)
    Inventors: Ulf Skarby, Karl Sahlman
  • Patent number: 7120465
    Abstract: A transceiver system is described herein that has an antenna coupled to a filter unit which is coupled to multiple radio base stations (RBSs). Each RBS uses one TX/RX cable and if needed a RX cable to connect to the filter unit. To enable the RBSs so they can share one antenna, each RBS has a duplex filter incorporated therein. And, the filter unit has a unique combination of diplex filter(s), duplex filter(s), part-band duplex filter(s), diplex-duplex filter(s), splitter(s) and/or low noise amplifier(s). Four exemplary embodiments of the transceiver system are described herein to show how the filter unit can be configured so as to enable the RBSs to share one antenna even if the RBSs share the same frequency band and/or even if the RBSs operate with different radio standards (e.g., TDMA, CDMA, WCDMA and GSM). Also described herein in accordance with the present invention are: (1) a method for constructing the transceiver system; (2) a radio base station; and (3) an antenna.
    Type: Grant
    Filed: December 20, 2003
    Date of Patent: October 10, 2006
    Assignee: Telefonaktiebolaget LM Ericsson (publ)
    Inventors: Ulf Skarby, S. Patrik Lindell
  • Patent number: 6925312
    Abstract: A first radio base station (281) and a second radio base station (282) are co-located at a base station site (20) and share the base station site's common antenna (22). The common (shared) antenna is connected through an amplifier (321) of the first radio base station (which serves as a master amplifier) and an antenna sharing unit 50 to remaining components (341) of the first radio base station, and also through the master amplifier and the antenna sharing unit to an amplifier (322) and remaining components (342) of the second radio base station. The antenna sharing unit (50), also known as the “coupler”, includes a tower mounted amplifier simulator (64).
    Type: Grant
    Filed: September 17, 2001
    Date of Patent: August 2, 2005
    Assignee: Telefonaktiebolaget LM Ericsson (publ)
    Inventor: Ulf Skarby
  • Publication number: 20050136875
    Abstract: A transceiver system is described herein that has an antenna coupled to a filter unit which is coupled to multiple radio base stations (RBSs). Each RBS uses one TX/RX cable and if needed a RX cable to connect to the filter unit. To enable the RBSs so they can share one antenna, each RBS has a duplex filter incorporated therein. And, the filter unit has a unique combination of diplex filter(s), duplex filter(s), part-band duplex filter(s), diplex-duplex filter(s), splitter(s) and/or low noise amplifier(s). Four exemplary embodiments of the transceiver system are described herein to show how the filter unit can be configured so as to enable the RBSs to share one antenna even if the RBSs share the same frequency band and/or even if the RBSs operate with different radio standards (e.g., TDMA, CDMA, WCDMA and GSM). Also described herein in accordance with the present invention are: (1) a method for constructing the transceiver system; (2) a radio base station; and (3) an antenna.
    Type: Application
    Filed: December 20, 2003
    Publication date: June 23, 2005
    Inventors: Ulf Skarby, S. Lindell
  • Publication number: 20030054861
    Abstract: A first radio base station (281) and a second radio base station (282) are co-located at a base station site (20) and share the base station site's common antenna (22). The common (shared) antenna is connected through an amplifier (321) of the first radio base station (which serves as a master amplifier) and an antenna sharing unit 50 to remaining components (341) of the first radio base station, and also through the master amplifier and the antenna sharing unit to an amplifier (322) and remaining components (342) of the second radio base station. The antenna sharing unit (50), also known as the “coupler”, includes a tower mounted amplifier simulator (64).
    Type: Application
    Filed: September 17, 2001
    Publication date: March 20, 2003
    Inventor: Ulf Skarby
  • Patent number: 6148217
    Abstract: The present invention discloses a method for quickly and easily adjusting the gain of an antenna system. According to an exemplary embodiment of the present invention, the output power of the base station's antenna system is adjusted during the base station's installation process. In the adjustment procedure, the output power of the base station is set to a predetermined value. When a switch is closed, the output power of the base station's associated active antenna system is measured and compared to a stored reference value. If the comparison indicates that the measured output power is above or below the stored reference value, the attenuation of the antenna system is automatically changed in order to properly adjust the gain of the antenna system. The present invention facilitates base station installation by providing a fast and easy gain adjustment method which requires no intervention from the base station or telephone network.
    Type: Grant
    Filed: August 19, 1998
    Date of Patent: November 14, 2000
    Assignee: Telefonaktiebolaget LM Ericsson
    Inventors: Ulf Skarby, Kristian Lindskog, Per Lofving
  • Patent number: 5551070
    Abstract: A system for transmission of combined, multi-carrier signals wherein combiner/filters, commonly called combiners, have been eliminated. A cartesian feedback loop linearizes the system and thereby suppresses carrier frequency intermodulation by feeding back a portion of the combined multi-carrier signal to each channel device.
    Type: Grant
    Filed: January 28, 1993
    Date of Patent: August 27, 1996
    Assignee: Telefonaktiebolaget LM Ericsson
    Inventors: Ulf Skarby, Par Bergsten, Bo Hedberg