Patents by Inventor Vimar Bjork

Vimar Bjork 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: 11569890
    Abstract: A transmission beam change method is disclosed for a wireless communication transmitter adapted to transmit an orthogonal frequency division multiplex (OFDM) signal using a transmission beam of a plurality of transmission beams available at the wireless communication transmitter. The method includes temporarily adapting an output power during a transmission beam change from one transmission beam to another transmission beam. In some embodiments, the transmission beam change is performed during a cyclic prefix (CP) of an OFDM symbol and the temporary adaptation is applied to only a part of the CP. Temporarily adapting the output power includes decreasing the output power to initiate the temporary adaptation and increasing the output power to terminate the temporary adaptation. In some embodiments, the temporary adaptation is performed during all transmission beam changes or only when an occurrence frequency of transmission beam changes is higher than a threshold value.
    Type: Grant
    Filed: April 4, 2018
    Date of Patent: January 31, 2023
    Assignee: Telefonaktiebolaget LM Ericsson (Publ)
    Inventors: Peter Jakobsson, Johan Thorebäck, Vimar Björk
  • Patent number: 11271299
    Abstract: In a method for calibrating at least two cross coupled antenna element groups in an antenna array, calibrating (S1) the antenna elements within each group of antenna elements. Further, in a respective calibration transceiver in each group, measuring (S2) a coupled signal within each group and a cross-coupled signal originating in another of the at least two groups. In addition, determining (S3) a respective relative phase and amplitude difference between said at least two groups based on the measured coupled signal and said cross-coupled signal, and determining (S4) the true phase and amplitude difference between the at least two groups based on the determined respective relative phase and amplitude differences. Finally, calibrating (S5) the at least two antenna groups based on the determined true phase and amplitude difference.
    Type: Grant
    Filed: July 6, 2016
    Date of Patent: March 8, 2022
    Assignee: TELEFONAKTIEBOLAGET LM ERICSSON (PUBL)
    Inventors: Christian Braun, Vimar Björk, Jonas Karlsson
  • Patent number: 11224022
    Abstract: A method performed by a radio network node for deciding an Automatic Gain Control (AGC) mode to be used for a received signal in a wireless communications network is provided. The radio network node estimates (301) a type of interference scenario affecting the received signal and obtains (302) information about channel quality of channels between the radio network node and connected wireless devices. Based on the estimated type of interference scenario and the obtained information about the channel quality, the radio network node dynamically decides (303) for the received signal, which AGC mode out of the following ACG modes to be used: —a slow AGC using a release timer for releasing an AGC state, —a fast AGC using a release timer for releasing an AGC state, and—a fast AGC using a trigger timer triggering an AGC state a first time interval before an interference period, and the release timer releasing the AGC state a second time interval after said interference period ends.
    Type: Grant
    Filed: September 19, 2017
    Date of Patent: January 11, 2022
    Assignee: TELEFONAKTIEBOLAGET LM ERICSSON (PUBL)
    Inventors: Jichang Liao, Vimar Björk, Erik Hammarberg
  • Publication number: 20210021324
    Abstract: A transmission beam change method is disclosed for a wireless communication transmitter adapted to transmit an orthogonal frequency division multiplex (OFDM) signal using a transmission beam of a plurality of transmission beams available at the wireless communication transmitter. The method includes temporarily adapting an output power during a transmission beam change from one transmission beam to another transmission beam. Typically, the transmission beam change is performed during a cyclic prefix (CP) of an OFDM symbol and the temporary adaptation is applied to only a part of the CP. Temporarily adapting the output power may include decreasing the output power to initiate the temporary adaptation and increasing the output power to terminate the temporary adaptation. For example, the temporary adaptation may be performed during all transmission beam changes or only when an occurrence frequency of transmission beam changes is higher than a threshold value.
    Type: Application
    Filed: April 4, 2018
    Publication date: January 21, 2021
    Inventors: Peter JAKOBSSON, Johan THOREBÄCK, Vimar BJÖRK
  • Patent number: 10833693
    Abstract: It is provided a provided a time-interleaved analog-to-digital converter (ADC) system comprising an input port configured to receive an analog signal, an ADC-array comprising M, M?2, ADCs arranged in parallel. Each ADC is configured to receive and to convert a portion of the analog signal into a digital signal at a sample rate fs. The ADC-system further comprises a reference ADC configured to receive and to convert the analog signal into a digital reference signal at an average sampling rate fref lower than fs. Each sampling instant of the reference ADC corresponds to a sampling instant of an ADC in the array of ADCs, and the ADC to select for each reference ADC sampling instant is randomized over time. The ADC-system also comprises a correction module configured to adjust the digital signal outputs of the ADC-array into a corrected digital output signal based on samples of the digital reference signal and the digital signals from the corresponding selected ADCs.
    Type: Grant
    Filed: May 29, 2015
    Date of Patent: November 10, 2020
    Assignee: TELEFONAKTIEBOLAGET LM ERICSSON (PUBL)
    Inventors: Vimar Björk, Claes Rolén
  • Publication number: 20200280936
    Abstract: A method performed by a radio network node for deciding an Automatic Gain Control (AGC) mode to be used for a received signal in a wireless communications network is provided. The radio network node estimates (301) a type of interference scenario affecting the received signal and obtains (302) information about channel quality of channels between the radio network node and connected wireless devices. Based on the estimated type of interference scenario and the obtained information about the channel quality, the radio network node dynamically decides (303) for the received signal, which AGC mode out of the following ACG modes to be used: —a slow AGC using a release timer for releasing an AGC state, —a fast AGC using a release timer for releasing an AGC state, and —a fast AGC using a trigger timer triggering an AGC state a first time interval before an interference period, and the release timer releasing the AGC state a second time interval after said interference period ends.
    Type: Application
    Filed: September 19, 2017
    Publication date: September 3, 2020
    Inventors: Jichang LIAO, Vimar BJÖRK, Erik HAMMARBERG
  • Publication number: 20200014105
    Abstract: In a method for calibrating at least two cross coupled antenna element groups in an antenna array, calibrating (S1) the antenna elements within each group of antenna elements. Further, in a respective calibration transceiver in each group, measuring (S2) a coupled signal within each group and a cross-coupled signal originating in another of the at least two groups. In addition, determining (S3) a respective relative phase and amplitude difference between said at least two groups based on the measured coupled signal and said cross-coupled signal, and determining (S4) the true phase and amplitude difference between the at least two groups based on the determined respective relative phase and amplitude differences. Finally, calibrating (S5) the at least two antenna groups based on the determined true phase and amplitude difference.
    Type: Application
    Filed: July 6, 2016
    Publication date: January 9, 2020
    Applicant: Telefonaktiebolaget LM Ericsson (publ)
    Inventors: Christian BRAUN, Vimar BJÖRK, Jonas KARLSSON
  • Patent number: 10432293
    Abstract: The present disclosure relates to a wireless communication node comprising at least one array antenna configured to receive a radio signal, said array antenna comprising a plurality of receiving antenna devices, each of said antenna devices being connected to a respective receiving circuit which is configured for processing said radio signal. Each receiving circuit comprises a demodulator, an analog-to-digital converter and a decoder, the demodulator being configured to receive an analog signal from the corresponding receiving antenna device and to output a demodulated analog signal to said analog-to-digital converter which outputs a converted digital signal to the decoder. Furthermore, the node is configured for adding a direct current, DC, offset value to said demodulated analog signal wherein the combined offset values of said node follow a predetermined distribution of values, having a variance, over the analog-to-digital converters.
    Type: Grant
    Filed: April 2, 2015
    Date of Patent: October 1, 2019
    Assignee: Telefonaktiebolaget LM Ericsson (publ)
    Inventors: Ulf Gustavsson, Sven Jacobsson, Giuseppe Durisi, Vimar Björk, Mikael Coldrey, Lars Sundström
  • Publication number: 20180138919
    Abstract: It is provided a provided a time-interleaved analog-to-digital converter (ADC) system comprising an input port configured to receive an analog signal, an ADC-array comprising M, M?2, ADCs arranged in parallel. Each ADC is configured to receive and to convert a portion of the analog signal into a digital signal at a sample rate fs. The ADC-system further comprises a reference ADC configured to receive and to convert the analog signal into a digital reference signal at an average sampling rate fref lower than fs. Each sampling instant of the reference ADC corresponds to a sampling instant of an ADC in the array of ADCs, and the ADC to select for each reference ADC sampling instant is randomized over time. The ADC-system also comprises a correction module configured to adjust the digital signal outputs of the ADC-array into a corrected digital output signal based on samples of the digital reference signal and the digital signals from the corresponding selected ADCs.
    Type: Application
    Filed: May 29, 2015
    Publication date: May 17, 2018
    Inventors: Vimar Björk, Claes Rolén
  • Publication number: 20180048377
    Abstract: The present disclosure relates to a wireless communication node comprising at least one array antenna configured to receive a radio signal, said array antenna comprising a plurality of receiving antenna devices, each of said antenna devices being connected to a respective receiving circuit which is configured for processing said radio signal. Each receiving circuit comprises a demodulator, an analog-to-digital converter and a decoder, the demodulator being configured to receive an analog signal from the corresponding receiving antenna device and to output a demodulated analog signal to said analog-to-digital converter which outputs a converted digital signal to the decoder. Furthermore, the node is configured for adding a direct current, DC, offset value to said demodulated analog signal wherein the combined offset values of said node follow a predetermined distribution of values, having a variance, over the analog-to-digital converters.
    Type: Application
    Filed: April 2, 2015
    Publication date: February 15, 2018
    Inventors: Ulf Gustavsson, Sven Jacobsson, Giuseppe Durisi, Vimar Björk, Mikael Coldrey, Lars Sundström
  • Patent number: 9350580
    Abstract: An aspect of the solution herein is directed to a receiver arrangement (100) including multiple RF-filters (RF1, RF2, RF3) and RF-attenuators (RF-A1, RF-A2, RF-A3), one for each of multiple frequency bands (RX1, RX2, RX3), where each RF-attenuator (RF-A1, RF-A2, RF-A3) is provided with a respective power splitter (PS1, PS2, PS3) that connects the RF-attenuator to an average power detector (Pave), which is configured to monitor an average power of each frequency band, where all frequency bands share a common antenna arrangement (110), at least one common LNA (112, 112a, 112b) and a common mixer arrangement (114) configured to mix all frequency bands into a common analog signal, and where a peak power monitor arrangement (201) is configured to monitor the peak power of the common analog signal, wherein, the receiver arrangement includes a digitizer arrangement (200) configured to control the gain of each RF-attenuator based on the monitored average power of each band from the average power detector and a detect
    Type: Grant
    Filed: September 25, 2013
    Date of Patent: May 24, 2016
    Assignee: TELEFONAKTIEBOLAGET LM ERICSSON (PUBL)
    Inventors: Georgios Sidiropoulos, Karl-Erik Assarsson, Vimar Björk
  • Publication number: 20150256372
    Abstract: An aspect of the solution herein is directed to a receiver arrangement (100) including multiple RF-filters (RF1, RF2, RF3) and RF-attenuators (RF-A1, RF-A2, RF-A3), one for each of multiple frequency bands (RX1, RX2, RX3), where each RF-attenuator (RF-A1, RF-A2, RF-A3) is provided with a respective power splitter (PS1, PS2, PS3) that connects the RF-attenuator to an average power detector (Pave), which is configured to monitor an average power of each frequency band, where all frequency bands share a common antenna arrangement (110), at least one common LNA (112, 112a, 112b) and a common mixer arrangement (114) configured to mix all frequency bands into a common analog signal, and where a peak power monitor arrangement (201) is configured to monitor the peak power of the common analog signal, wherein, the receiver arrangement includes a digitizer arrangement (200) configured to control the gain of each RF-attenuator based on the monitored average power of each band from the average power detector and a detect
    Type: Application
    Filed: September 25, 2013
    Publication date: September 10, 2015
    Applicant: TELEFONAKTIEBOLAGET L M ERICSSON (PUBL)
    Inventors: Georgios Sidiropoulos, Karl-Erik Assarsson, Vimar Björk
  • Patent number: 9113430
    Abstract: The invention discloses a base station (110, 300) for a cell (105) in a cellular communications system (100). The base station comprises a scheduler (310) for scheduling transmissions to users (115, 120) in the cell (105) and a transmitter with a power amplifier (325). The scheduler (310) is also arranged to set the output power level of the power amplifier (325) for an upcoming transmission period.
    Type: Grant
    Filed: March 3, 2009
    Date of Patent: August 18, 2015
    Assignee: Telefonaktiebolaget L M Ericsson (publ)
    Inventors: Jacob Österling, Vimar Björk
  • Patent number: 8849224
    Abstract: The invention provides a receiver comprising an input end, an Rx-chain with at least one regulating means and an output end. The receiver further comprises a feedback loop in the Rx-chain, the regulating means arranged for providing a higher or lower gain setting. The feedback loop comprises an AGC Multilevel threshold detector unit, AMU. The AMU comprises at least one Low Multilevel Threshold Detector, LMTD, and the LMTD comprises at least two threshold detectors, each detector having an associated low threshold level and detection interval, the length of the detection interval being shorter the lower the low threshold level is arranged to be set. The higher gain setting being arranged to be initiated through the feedback loop when the absolute level of an AGC input signal has been below at least one of the low threshold levels during the entire detection interval associated with that low threshold level.
    Type: Grant
    Filed: May 15, 2008
    Date of Patent: September 30, 2014
    Assignee: Optis Cellular Technology, LLC
    Inventor: Vimar Björk
  • Patent number: 8787853
    Abstract: A receiver circuit comprising first and second receivers for demodulating first and second parts, respectively, of a received signal. The receiver circuit also comprises an adjustment circuit for adjusting the demodulated signal from the first receiver. The output signal from the adjustment circuit is used as output signal from the receiver circuit which also comprises an adjustment value circuit for determining an adjustment value for the adjustment circuit in adjusting the output signal from the first receiver. The adjustment value circuit receives the demodulated signal from the second receiver and the output signal from the adjustment circuit and uses differences between these input signals for forming said adjustment value. The first receiver and the second receiver have different transfer functions within one and the same frequency range.
    Type: Grant
    Filed: December 29, 2010
    Date of Patent: July 22, 2014
    Assignee: Telefonaktiebolaget L M Ericsson (Publ)
    Inventors: Derek Hagen, Vimar Bjork, Claes Rolen, Torbjorn Gunnar Widhe
  • Patent number: 8582700
    Abstract: The present solution relates to a method in a first communication node (501) for suppressing noise in a communication system (500) utilizing an automatic gain control. The first communication node (501) receives (1301) a signal from a second communication node (503). Then, the first communication node (501) determines (1302) if a gain level is changed. The signal gain is changed (1303). The next step is for the first communication node (501) to determine (1305) if an inband interferer is present, and then to suppress (1306) transient noise in the signal.
    Type: Grant
    Filed: February 22, 2010
    Date of Patent: November 12, 2013
    Assignee: Telefonaktiebolaget L M Ericsson (publ)
    Inventors: Derek Hagen, Vimar Bjork, Claes Rolen
  • Patent number: 8582704
    Abstract: A communication method for use in a first cellular communications system is proposed for minimizing the interference caused by strong interfering pulses in the same frequency band as the system or an adjacent frequency band. The method comprises the steps of Receiving an incoming signal Bandpass filtering the incoming signal to filter out a first frequency band (B1) used by the communications system and forwarding the bandpass filtered signal to a receiver unit (35) for processing and forwarding the processed signal to a signal detector (37) arranged to detect the wanted signal. Redirecting a fraction of the received signal and detecting the power of the redirected fraction. Using the detected power to modify the function of the signal detector (37).
    Type: Grant
    Filed: April 8, 2008
    Date of Patent: November 12, 2013
    Assignee: Telefonaktiebolaget L M Ericsson (Publ)
    Inventors: Johan Axnas, Vimar Bjork, Markus Ringstrom
  • Publication number: 20130288623
    Abstract: A receiver circuit comprising first and second receivers for demodulating first and second parts, respectively, of a received signal. The receiver circuit also comprises an adjustment circuit for adjusting the demodulated signal from the first receiver. The output signal from the adjustment circuit is used as output signal from the receiver circuit which also comprises an adjustment value circuit for determining an adjustment value for the adjustment circuit in adjusting the output signal from the first receiver. The adjustment value circuit receives the demodulated signal from the second receiver and the output signal from the adjustment circuit and uses differences between these input signals for forming said adjustment value. The first receiver and the second receiver have different transfer functions within one and the same frequency range.
    Type: Application
    Filed: December 29, 2010
    Publication date: October 31, 2013
    Applicant: TELEFONAKTIEBOLAGET L M ERICSSON (PUBL)
    Inventors: Derek Hagen, Vimar Bjork, Claes Rolen, Torbjorn Gunnar Widhe
  • Publication number: 20130244602
    Abstract: A receiver system with controllable attenuators and a component with a limited input range, arranged to receive as its input signal the output signal from the attenuators. The receiver system also comprises a compensation circuit which varies the level of the output signal of the component and a control loop which monitors the component and controls at least one attenuator to be active or inactive so that the level of the signal to the component is within the input range, and controls the compensation circuit to keep the output signal of the component constant. The control of the compensation circuit and attenuators between the component and said at least one attenuator is carried out in synchronicity with the propagation of the received signal through the attenuator chain from said at least one attenuator.
    Type: Application
    Filed: November 17, 2010
    Publication date: September 19, 2013
    Applicant: TELEFONAKTIEBOLAGET L M ERICSSON (PUBL)
    Inventors: Derek Hagen, Vimar Bjork, Claes Rolen
  • Patent number: 8320865
    Abstract: The present invention relates to a method, an Automatic Gain Control control unit and a receiver for Noise change output signalling. It also relates to an Adjustment Unit, a receiver and a base band detector for adjustment of an Automatic Gain Control output signal on the basis of the Noise change output signalling. In a first step a receiver receives a communication input signal. In a second step at least one Automatic Gain Control attenuator or amplifier in the receiver attenuates the communication input signal. In a third step the receiver produces at least one AGC output signal. In a fourth step at least one AGC control unit in the receiver initiates a changed gain setting on the receiver, when the level of an AGC control unit input signal received by the unit has been below a first threshold level or above a second threshold level during a detection interval.
    Type: Grant
    Filed: May 15, 2008
    Date of Patent: November 27, 2012
    Assignee: Telefonaktiebolaget L M Ericsson (Publ)
    Inventor: Vimar Björk