Patents by Inventor Barbu Popescu

Barbu Popescu 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: 8988145
    Abstract: A high fidelity current dumping audio amplifier in which for achieving the best performance are combined the feedforward error correction and the negative feedback. The principle of feedforward error correction in a balanced bridge in A.C. is used, including the whole audio frequency amplifier, combined with a classical negative feedback that includes the items of the amplification chain likely to introduce distortions. The amplifier can be built in a current amplifier structure or in a voltage amplifier structure. The current amplifier structure contains an operational amplifier used as a voltage-current converter and signal de-phasing, two low power symmetrical current amplifiers operating in “A” class with a current mirror structure and a power stage in “B” class, with no quiescent current. The voltage structure of the amplifier contains an operational voltage amplifier, a low power amplifier operating in “A” class, and a power stage operating in “B” class.
    Type: Grant
    Filed: November 24, 2012
    Date of Patent: March 24, 2015
    Inventor: Barbu Popescu
  • Patent number: 8787504
    Abstract: Schemes for combining channel-estimates from different OFDM frames after compensating for changes in receiver-transmitter characteristics.
    Type: Grant
    Filed: November 16, 2012
    Date of Patent: July 22, 2014
    Assignee: Cambridge Silicon Radio Limited
    Inventor: Andrei Barbu Popescu
  • Publication number: 20140078958
    Abstract: A station for accessing the resources of an access point in a wireless network, the station including a transmitter that is arranged to formulate probe requests and a transmit chain that is arranged to transmit probe requests on multiple channels of the access point simultaneously, wherein the probe requests are configured to elicit responses from the access point.
    Type: Application
    Filed: September 20, 2012
    Publication date: March 20, 2014
    Applicant: Cambridge Silicon Radio Limited
    Inventors: Andrei Barbu Popescu, Martin Robert Evans, Paul Christopher McFarthing
  • Patent number: 8498596
    Abstract: A signal quality estimator for estimating the quality of signal reception in a signal receiver, the signal quality estimator comprising: a first filter for filtering a signal received by the receiver to isolate a frequency band therein; and a signal analyzer for forming an indication of the degree to which the amplitude of the signal in that frequency band varies over time, to serve as an estimate of the quality of signal reception in the receiver.
    Type: Grant
    Filed: November 29, 2007
    Date of Patent: July 30, 2013
    Assignee: Cambridge Silicon Radio Limited
    Inventor: Andrei Barbu Popescu
  • Publication number: 20130181778
    Abstract: A high fidelity current dumping audio amplifier in which for achieving the best performance are combined the feedforward error correction and the negative feedback. The principle of feedforward error correction in a balanced bridge in A.C. is used, including the whole audio frequency amplifier, combined with a classical negative feedback that includes the items of the amplification chain likely to introduce distortions. The amplifier can be built in a symmetrical or in a asymmetrical structure. The symmetrical structure of the amplifier contains an operational amplifier used as a voltage-current converter and signal de-phasing, two low power symmetrical amplifiers in “A” class with a current mirror structure with local feedback and a power stage in “B” class, with no quiescent current. The asymmetrical structure of the amplifier contains an operational amplifier, a low power amplifier in “A” class, and a power stage in “B” class.
    Type: Application
    Filed: November 24, 2012
    Publication date: July 18, 2013
    Inventor: Barbu Popescu
  • Patent number: 8295872
    Abstract: Improved power control methods and power control systems are described wherein received RSSI values are processed to generate a power control signal which may be used by a link manager, or other element in a receiving station, to determine whether to send a power control message to the transmitting station. The method used to process the received RSSI values is dependent upon a value of the power measurement, for example, the method may involve a comparison between the value of the power measurement and a value of the power control signal. In another embodiment, the received RSSI values may be converted to power values and then smoothed using a filter.
    Type: Grant
    Filed: October 22, 2009
    Date of Patent: October 23, 2012
    Assignee: Cambridge Silicon Radio Ltd.
    Inventors: Paul Wright, James Digby Yarlet Collier, Andrei Barbu Popescu
  • Patent number: 8203944
    Abstract: A method for transmitting data over a network in which multiple transmission conditions can be used for transmitting data, the method comprising selecting a transmission condition to be used when transmitting data over the network, said selection being made in dependence on a predetermined preference distribution that for each of the multiple transmission conditions defines a probability of that transmission condition being selected, using the selected transmission condition when transmitting data over the network and determining the success of the transmission and updating the preference distribution in dependence on the success of the transmission and thereafter selecting a transmission condition for transmitting data over the network in dependence on the updated preference distribution.
    Type: Grant
    Filed: November 9, 2007
    Date of Patent: June 19, 2012
    Assignee: Cambridge Silicon Radio Limited
    Inventors: Andrei Barbu Popescu, Timothy Condren Smith, Peter William Stephenson
  • Patent number: 8023917
    Abstract: An interference rejection unit for at least partially rejecting a narrowband interferer from an input signal, the unit comprising: an interferer detector for detecting the phase of an interferer in the input signal; a signal generator for generating a cancellation signal in dependence on the phase detected by the interferer detector; and a signal combiner for combining the input signal with the tone cancellation signal to generate an output signal in which the interferer is at least partially cancelled from the input signal.
    Type: Grant
    Filed: January 18, 2007
    Date of Patent: September 20, 2011
    Assignee: Cambridge Silicon Radio Limited
    Inventor: Andrei Barbu Popescu
  • Patent number: 8023487
    Abstract: A method for transmitting data over a network in which multiple transmission conditions can be used for transmitting data, each transmission condition being associated with a rating indicative of how successful previous data transmissions using that transmission condition have been, the method comprising using a selected transmission condition when transmitting data over the network and updating the rating associated with the selected transmission condition in dependence on the success of that transmission, updating the ratings associated with the transmission conditions other than the selected transmission condition by adjusting each of those ratings by a predetermined amount and selecting a transmission condition in dependence on the updated ratings.
    Type: Grant
    Filed: November 9, 2007
    Date of Patent: September 20, 2011
    Assignee: Cambridge Silicon Radio Limited
    Inventors: Andrei Barbu Popescu, Timothy Condren Smith, Peter William Stephenson
  • Publication number: 20100219876
    Abstract: An interference rejection unit for at least partially rejecting a narrowband interferer from an input signal, the unit comprising: an interferer detector for detecting the phase of an interferer in the input signal; a signal generator for generating a cancellation signal in dependence on the phase detected by the interferer detector; and a signal combiner for combining the input signal with the tone cancellation signal to generate an output signal in which the interferer is at least partially cancelled from the input signal.
    Type: Application
    Filed: January 18, 2007
    Publication date: September 2, 2010
    Applicant: CAMBRIDGE SILICON RADIO LIMITED
    Inventor: Andrei Barbu Popescu
  • Publication number: 20100151807
    Abstract: A signal quality estimator for estimating the quality of signal reception in a signal receiver, the signal quality estimator comprising: a first filter for filtering a signal received by the receiver to isolate a frequency band therein; and a signal analyzer for forming an indication of the degree to which the amplitude of the signal in that frequency band varies over time, to serve as an estimate of the quality of signal reception in the receiver.
    Type: Application
    Filed: November 29, 2007
    Publication date: June 17, 2010
    Applicant: CAMBRIDGE SILICON RADIO LIMITED
    Inventor: Andrei Barbu Popescu
  • Publication number: 20100105421
    Abstract: Improved power control methods and power control systems are described wherein received RSSI values are processed to generate a power control signal which may be used by a link manager, or other element in a receiving station, to determine whether to send a power control message to the transmitting station. The method used to process the received RSSI values is dependent upon a value of the power measurement, for example, the method may involve a comparison between the value of the power measurement and a value of the power control signal. In another embodiment, the received RSSI values may be converted to power values and then smoothed using a filter.
    Type: Application
    Filed: October 22, 2009
    Publication date: April 29, 2010
    Applicant: Cambridge Silicon Radio Ltd.
    Inventors: Paul Wright, James Digby Yarlet Collier, Andrei Barbu Popescu
  • Publication number: 20080117814
    Abstract: A method for transmitting data over a network in which multiple transmission conditions can be used for transmitting data, the method comprising selecting a transmission condition to be used when transmitting data over the network, said selection being made in dependence on a predetermined preference distribution that for each of the multiple transmission conditions defines a probability of that transmission condition being selected, using the selected transmission condition when transmitting data over the network and determining the success of the transmission and updating the preference distribution in dependence on the success of the transmission and thereafter selecting a transmission condition for transmitting data over the network in dependence on the updated preference distribution.
    Type: Application
    Filed: November 9, 2007
    Publication date: May 22, 2008
    Applicant: Cambridge Silicon Radio Limited
    Inventors: Andrei Barbu Popescu, Timothy Condren Smith, Peter William Stephenson
  • Publication number: 20080117888
    Abstract: A method for transmitting data over a network in which multiple transmission conditions can be used for transmitting data, each transmission condition being associated with a rating indicative of how successful previous data transmissions using that transmission condition have been, the method comprising using a selected transmission condition when transmitting data over the network and updating the rating associated with the selected transmission condition in dependence on the success of that transmission, updating the ratings associated with the transmission conditions other than the selected transmission condition by adjusting each of those ratings by a predetermined amount and selecting a transmission condition in dependence on the updated ratings.
    Type: Application
    Filed: November 9, 2007
    Publication date: May 22, 2008
    Applicant: Cambridge Silicon Radio Limited
    Inventors: Andrei Barbu Popescu, Timothy Condren Smith, Peter William Stephenson