Patents by Inventor Lars Sundström
Lars Sundström 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).
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Patent number: 8477886Abstract: A radio-receiver circuit having an analog-to-digital conversion unit. The analog-to-digital conversion unit comprises an analog-to-digital converter (ADC), and a filter operatively connected to an input terminal of the ADC in a receive path of the radio-receiver circuit. The radio-receiver circuit further comprises a control unit adapted to receive control data and determine, based on the control data, a frequency band in which data is to be transmitted to the radio-receiver circuit during a subsequent time interval. Furthermore, the control unit is operative to adapt at least one frequency characteristic of the analog-to-digital conversion unit to the determined frequency band for receiving said data transmitted in said subsequent time interval.Type: GrantFiled: May 6, 2009Date of Patent: July 2, 2013Assignee: Telefonaktiebolaget L M Ericsson (Publ)Inventors: Bengt Lindoff, Filip Oredsson, Tony Petersson, Lars Sundström
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Publication number: 20130155748Abstract: A conversion circuit (20) for converting a complex analog input signal having an in-phase, I, component and a quadrature-phase, Q, component resulting from frequency down conversion of a radio-frequency, RF, signal (XRF) to a frequency band covering 0 Hz into a digital representation is disclosed. It comprises a channel-selection filter unit (40) arranged to filter the complex analog input signal, thereby generating a channel-filtered I and Q components, and one or more processing units (53, 53a-b). Each processing unit comprises four mixers (60-75) for generating a first and a second frequency-translated I component and a first and a second channel-filtered Q component based on two LO signals with equal LO frequency and a 90° mutual phase shift. Furthermore, each processing unit comprises a combiner unit (85, 120) for generating a first, a second, a third, and a fourth combined signal proportional to sums and differences between said frequency translated I and Q components.Type: ApplicationFiled: June 13, 2011Publication date: June 20, 2013Applicant: TELEFONAKTIEBOLAGET L M ERICSSON (PUBL)Inventors: Lars Sundström, Roland Strandberg
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Patent number: 8412139Abstract: Methods may be provided to simultaneously receive first and second RF (radio frequency) carriers over respective first and second RF carrier frequencies. More particularly, the first and second RF carriers may be provided at an RF mixer stage. During a first time period, the first and second RF carriers may be down converted through the RF mixer stage using a first RF mixer frequency to generate first downconverted signals, and the first downconverted signals may be processed to provide first and second DC carriers corresponding to the first and second RF earners. During a second time period, the first and second RF carriers may be downconverted through the RF mixer stage using a second RF mixer frequency to generate second downconverted signals with the first and second RF mixer frequencies being different, and the second downconverted signals may be processed to provide the first and second DC carriers corresponding to the first and second RF carriers. Related devices are also discussed.Type: GrantFiled: January 10, 2011Date of Patent: April 2, 2013Assignee: Telefonaktiebolaget L M Ericsson (Publ)Inventors: Chester Park, Lars Sundström, Ali S. Khayrallah
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Publication number: 20130044619Abstract: Levels of power reduction for signals to be transmitted from a mobile communications device via radio channels in a digital wireless communications system, where each signal is modulated according to one of a number of modulation configurations, are determined. For each modulation configuration a first estimate of a power reduction is calculated (101), and the calculated first estimates are storied (102) in the device. The method comprises the steps of determining (103) a limited set of modulation configurations, said limited set comprising modulation configurations that have been determined likely to be used in practice; calculating (104) for each modulation configuration of the limited set an optimized estimate of a power reduction; and storing (105) the calculated optimized estimates in the device. In this way the power consumption of the device is reduced while keeping a look-up table at a reasonable size.Type: ApplicationFiled: December 22, 2009Publication date: February 21, 2013Applicant: TELEFONAKTIEBOLAGET L M ERICSSON (PUBL)Inventors: Anders Wallén, Lars Sundström
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Patent number: 8331506Abstract: RF impairment parameters, including frequency-dependent IQ imbalance, are estimated in a wideband received signal on a per-sub-band (or per sub-band pair) basis. In one embodiment, block-type pilot signals are received, such as on SCH, and IQ imbalance and carrier frequency offset are estimated from the block-type pilot signals. The block-type pilot signals may be received in only one sub-band. Data and comb-type pilot signals are then received on all sub-bands. Phase noise and channel coefficients are estimated for the first sub-band, based on the IQ imbalance and carrier frequency offset estimates. IQ imbalance is then successively estimated, on a per-sub-band (or per sub-band pair) basis, based on the comb-type pilot signals, the previously estimated carrier frequency offset estimate, and the phase noise and IQ imbalance estimates from prior sub-bands (or pairs). This may comprise iterative estimation based on decision feedback.Type: GrantFiled: March 12, 2010Date of Patent: December 11, 2012Assignee: Telefonaktiebolaget L M Ericsson (Publ)Inventors: Chester Park, Leif Wilhelmsson, Lars Sundström
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Publication number: 20120307660Abstract: The present disclosure relates to a technique for performing physical layer measurements on a frequency resource relative to other frequency resources in a telecommunications system operable to communicate over multiple frequency resources.Type: ApplicationFiled: November 25, 2010Publication date: December 6, 2012Applicant: TELEFONAKTIEBOLAGET LM ERICSSON (PUBL)Inventors: Bengt Lindoff, Robert Baldemair, Lars Sundström
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Patent number: 8311483Abstract: User equipment comprising a receiver obtains information about a set of channels to be sensed in a sensing process, wherein each channel is associated with a respective one of a number of radio frequencies. The receiver obtains a radio frequency signal by simultaneously sensing two or more of the channels included in the set of channels. A total power level of the sensed two or more channels is measured, and a comparison result is generated by comparing the total power level of the sensed two or more channels with a predetermined power level. The user equipment is controlled based on the comparison result. For example, if the total power level is below a threshold, then the sensed channels can be considered to not be in use by external transmission equipment.Type: GrantFiled: March 9, 2010Date of Patent: November 13, 2012Assignee: Telefonaktiebolaget L M Ericsson (publ)Inventors: Fredrik Tillman, Anders Rosenqvist, Lars Sundström
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Patent number: 8279971Abstract: A level of power reduction for a transmitter arranged to transmit signals modulated according to one of a number of modulation configurations via radio channels in a digital wireless communications system is estimated. Modulation dependent data comprising a term calculated from a third order product of a signal modulated according to a modulation configuration are provided, and a power reduction estimate for transmission of signals modulated according to said modulation configuration is calculated there from. The modulation dependent data are provided to comprise, in addition to the term calculated from a third order product, at least one term calculated from a higher order product. Further, transmitter dependent data are provided, and the estimate is calculated from said modulation dependent and transmitter dependent data. Thus a more accurate method of determining a power reduction is achieved, which also allows different operating conditions for the transmitter to be considered.Type: GrantFiled: December 19, 2007Date of Patent: October 2, 2012Assignee: Telefonaktiebolaget LM Ericsson (publ)Inventors: Lars Sundström, Torgny Palenius
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Publication number: 20120182958Abstract: In a multi-carrier wireless system, potential problems from reconfiguring mobile station resources to accommodate changes in component-carrier configuration are mitigated by inserting a guard period each time the configuration of component carriers changes, so that transceiver reconfiguration can be carried out without interfering with ongoing transmission. A base station is configured to transmit data to a mobile station according to a first configuration of two or more component carriers, to determine that a change of configuration to a second component-carrier configuration is required, and to signal the change of configuration to the mobile station, using the first configuration of component carriers. The base station then refrains from transmitting data to the mobile station during a pre-determined guard interval of at least one transmission-time interval subsequent to the signaling of the change of configuration.Type: ApplicationFiled: December 22, 2009Publication date: July 19, 2012Applicant: TELEFONAKTIEBOLAGET LM ERICSSON (PUBL)Inventors: Ghyslain Pelletier, Lars Sundström
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Publication number: 20120177147Abstract: Methods may be provided to simultaneously receive first and second RF (radio frequency) carriers over respective first and second RF carrier frequencies. More particularly, the first and second RF carriers may be provided at an RF mixer stage. During a first time period, the first and second RF carriers may be down converted through the RF mixer stage using a first RF mixer frequency to generate first downconverted signals, and the first downconverted signals may be processed to provide first and second DC carriers corresponding to the first and second RF earners. During a second time period, the first and second RF carriers may be downconverted through the RF mixer stage using a second RF mixer frequency to generate second downconverted signals with the first and second RF mixer frequencies being different, and the second downconverted signals may be processed to provide the first and second DC carriers corresponding to the first and second RF carriers. Related devices are also discussed.Type: ApplicationFiled: January 10, 2011Publication date: July 12, 2012Inventors: Chester Park, Lars Sundström, Ali S. Khayrallah
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Patent number: 8219056Abstract: A device may include a measurement receiver, a communication receiver, and a transmitter. The measurement receiver may include a receiver (RX) down-conversion component to receive an amplified signal from a low-noise amplifier of the communication receiver, selectively receive a signal from a first local oscillator associated with the communication receiver or a second local oscillator associated with the transmitter, and down-convert the amplified signal to baseband using the received signal from the first local oscillator or the second local oscillator. The measurement receiver may further include a delta-sigma analog-to-digital converter (ADC) to provide low quantization noise only for a particular frequency range to be measured, and a control component to configure the delta-sigma ADC to provide the low quantization noise at the particular frequency range.Type: GrantFiled: September 3, 2009Date of Patent: July 10, 2012Assignee: Telefonaktiebolaget L M Ericsson (publ)Inventors: Lars Sundström, Thomas Olsson, Leif Wilhelmsson, Chester Park
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Publication number: 20120155407Abstract: A method of scheduling wireless data transmissions between a mobile terminal (701) and a base station using multiple component carrier signals is disclosed. The method comprises the steps of: receiving in the mobile terminal information from the base station indicating available component carriers; detecting in the mobile terminal at least one dynamic parameter indicative of the mobile terminal's current ability to handle component carriers having non-contiguous bandwidths; determining in the mobile terminal in dependence of the at least one dynamic parameter which of the available component carriers to utilize; and transmitting from the mobile terminal to the base station information indicating the component carriers determined to utilize.Type: ApplicationFiled: May 31, 2010Publication date: June 21, 2012Applicant: TELEFONAKTIEBOLAGET L M ERICSSON (PUBL)Inventors: Bengt Lindoff, Stefan Andersson, Ylva Jading, Stefan Parkvall, Lars Sundström
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Publication number: 20120113935Abstract: A method of scheduling wireless data transmissions between a mobile terminal and a base station using multiple system carrier signals is disclosed. The method comprises the steps of receiving (101) the mobile terminal information from the base station indicating available system carriers; detecting (102) at least one dynamic parameter indicative of the mobile terminal's current capability to handle non-contiguous system carriers; determining (103) from the dynamic parameter whether a situation has occurred where the mobile terminal's capability to handle non-contiguous system carriers has been reduced; modifying (104), in such case, feedback information to be transmitted to the base station; and transmitting (105) the modified feedback information to the base station.Type: ApplicationFiled: June 2, 2010Publication date: May 10, 2012Applicant: Telefonaktiebolaget L M Ericsson (publ)Inventors: Bengt Lindoff, Stefan Andersson, Lars Sundström
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Publication number: 20120087443Abstract: A radio circuit comprises an interface unit for communicating data and commands over a communication link between a digital baseband circuit and the radio circuit. Furthermore, the radio circuit comprises an event-scheduling unit, a local time-reference unit, a synchronization unit, and an execution-control unit. The event-scheduling unit is arranged to receive event-request commands specifying an event to be executed in the radio circuit and a time instant at which the specified event is to be executed, from the digital baseband circuit. Furthermore, the event-scheduling unit is arranged to, in response to receiving an event request-command, schedule the specified event to be executed on the specified time instant. The execution-control unit is arranged to issue execution of each scheduled event at the scheduled time instant based on time information from the local time reference unit.Type: ApplicationFiled: March 23, 2009Publication date: April 12, 2012Inventors: Thomas Olsson, Lars Sundström
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Patent number: 8150338Abstract: A method and apparatus taught herein reduce the peak-to-average ratio (PAR) of a complex-valued signal based on detecting peaks in the signal that are above a peak threshold, characterizing the detected peaks in Cartesian coordinates, generating cancellation pulses in Cartesian coordinates based on the detected peak characterizations. PAR reduction processing continues with canceling the detected peaks by combining the cancellation pulses with a correspondingly delayed version of the signal. Advantageously, peak detection may be performed in polar form using a computationally efficient peak detection algorithm that avoids calculation of the I and Q peak waveforms unless a signal peak beyond a defined threshold is present. In one or more embodiments, the generation and use of asymmetric and/or shaped cancellation pulses offers further performance advantages.Type: GrantFiled: July 12, 2011Date of Patent: April 3, 2012Assignee: Telefonaktiebolaget LM Ericsson (publ)Inventor: Lars Sundström
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Publication number: 20110268167Abstract: A method and apparatus taught herein reduce the peak-to-average ratio (PAR) of a complex-valued signal based on detecting peaks in the signal that are above a peak threshold, characterizing the detected peaks in Cartesian coordinates, generating cancellation pulses in Cartesian coordinates based on the detected peak characterizations. PAR reduction processing continues with canceling the detected peaks by combining the cancellation pulses with a correspondingly delayed version of the signal. Advantageously, peak detection may be performed in polar form using a computationally efficient peak detection algorithm that avoids calculation of the I and Q peak waveforms unless a signal peak beyond a defined threshold is present. In one or more embodiments, the generation and use of asymmetric and/or shaped cancellation pulses offers further performance advantages.Type: ApplicationFiled: July 12, 2011Publication date: November 3, 2011Inventor: Lars Sundström
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Publication number: 20110268232Abstract: Digital IQ imbalance estimation and compensation is facilitated by shaping the frequency response of receiver branches. In particular, in a multi-carrier receiver, the frequency response of signal processing elements in at least one receiver branch is set to not fully attenuate received signals in a frequency band of interest. The frequency band of interest is greater than the carrier bandwidth of the received signal processed by that receiver branch. In some embodiments, the received signal is not attenuated, and adjacent interfering signals are partially attenuated. This allows information regarding the interfering signals to appear in an IQ imbalance-induced, inter-carrier image of the signals in anther receiver branch, facilitating digital estimation and compensation of IQ imbalance.Type: ApplicationFiled: May 2, 2011Publication date: November 3, 2011Inventors: Chester Park, Lars Sundström, Jim Svensson
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Publication number: 20110222638Abstract: RF impairment parameters, including frequency-dependent IQ imbalance, are estimated in a wideband received signal on a per-sub-band (or per sub-band pair) basis. In one embodiment, block-type pilot signals are received, such as on SCH, and IQ imbalance and carrier frequency offset are estimated from the block-type pilot signals. The block-type pilot signals may be received in only one sub-band. Data and comb-type pilot signals are then received on all sub-bands. Phase noise and channel coefficients are estimated for the first sub-band, based on the IQ imbalance and carrier frequency offset estimates. IQ imbalance is then successively estimated, on a per-sub-band (or per sub-band pair) basis, based on the comb-type pilot signals, the previously estimated carrier frequency offset estimate, and the phase noise and IQ imbalance estimates from prior sub-bands (or pairs). This may comprise iterative estimation based on decision feedback.Type: ApplicationFiled: March 12, 2010Publication date: September 15, 2011Inventors: Chester Park, Leif Wilhelmsson, Lars Sundström
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Publication number: 20110223877Abstract: User equipment comprising a receiver obtains information about a set of channels to be sensed in a sensing process, wherein each channel is associated with a respective one of a number of radio frequencies. The receiver obtains a radio frequency signal by simultaneously sensing two or more of the channels included in the set of channels. A total power level of the sensed two or more channels is measured, and a comparison result is generated by comparing the total power level of the sensed two or more channels with a predetermined power level. The user equipment is controlled based on the comparison result. For example, if the total power level is below a threshold, then the sensed channels can be considered to not be in use by external transmission equipment.Type: ApplicationFiled: March 9, 2010Publication date: September 15, 2011Inventors: Fredrik Tillman, Anders Rosenqvist, Lars Sundström
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Patent number: 7995975Abstract: A method and apparatus taught herein reduce the peak-to-average ratio (PAR) of a complex-valued signal based on detecting peaks in the signal that are above a peak threshold, characterizing the detected peaks in Cartesian coordinates, generating cancellation pulses in Cartesian coordinates based on the detected peak characterizations. PAR reduction processing continues with canceling the detected peaks by combining the cancellation pulses with a correspondingly delayed version of the signal. Advantageously, peak detection may be performed in polar form using a computationally efficient peak detection algorithm that avoids calculation of the I and Q peak waveforms unless a signal peak beyond a defined threshold is present. In one or more embodiments, the generation and use of asymmetric and/or shaped cancellation pulses offers further performance advantages.Type: GrantFiled: December 21, 2006Date of Patent: August 9, 2011Assignee: Telefonaktiebolaget LM Ericsson (publ)Inventor: Lars Sundström