Patents Assigned to Dali Systems Co. Ltd.
  • Publication number: 20140306841
    Abstract: A system for indoor localization using satellite navigation signals in a Distributed Antenna System includes a plurality of Off-Air Access Units (OAAUs). Each of the plurality of OAAUs is operable to receive an individual satellite navigation signal from at least one of a plurality of satellites and operable to route signals optically to one or more DAUs. The system also includes a plurality of remote DRUs located at a remote location. The plurality of remote DRUs are operable to receive signals from a plurality of local DAUs. The system further includes an algorithm to delay each individual satellite navigation signal for providing indoor localization at each of the plurality of DRUs and a GPS receiver at the remote location used in a feedback loop with the DRU to control the delays.
    Type: Application
    Filed: February 3, 2014
    Publication date: October 16, 2014
    Applicant: Dali Systems Co. Ltd.
    Inventor: Shawn Patrick Stapleton
  • Patent number: 8855234
    Abstract: An efficient baseband predistortion linearization method for reducing the spectral regrowth and compensating memory effects in wideband communication systems using effective multiplexing modulation technique such as wideband code division multiple access and orthogonal frequency division multiplexing is disclosed. The present invention is based on the method of piecewise pre-equalized lookup table based predistortion, which is a cascade of a lookup table predistortion and piecewise pre-equalizers.
    Type: Grant
    Filed: May 3, 2013
    Date of Patent: October 7, 2014
    Assignee: Dali Systems Co. Ltd.
    Inventors: Wan Jong Kim, Kyoung Joon Cho, Jong Heon Kim, Shawn Patrick Stapleton
  • Patent number: 8848766
    Abstract: A remote radio head unit (RRU) system for achieving high data rate communications in a Distributed Antenna System is disclosed. The Distributed Antenna System is configured as a Neutral Host enabling multiple operators to exist on one DAS system. The present disclosure enables a remote radio head unit to be field reconfigurable and support multi-modulation schemes (modulation-independent), multi-carriers, multi-frequency bands and multi-channels. As a result, the remote radio head system is particularly suitable for wireless transmission systems, such as base-stations, repeaters, and indoor signal coverage systems.
    Type: Grant
    Filed: August 16, 2011
    Date of Patent: September 30, 2014
    Assignee: Dali Systems Co. Ltd.
    Inventors: Paul Lemson, Shawn Patrick Stapleton, Sasa Trajko Trajkovic
  • Publication number: 20140286247
    Abstract: The present disclosure is a novel utility of a software defined radio (SDR) based Distributed Antenna System (DAS) that is field reconfigurable and support multi-modulation schemes (modulation-independent), multi-carriers, multi-frequency bands and multi-channels. The present disclosure enables a high degree of flexibility to manage, control, enhance, facilitate the usage and performance of a distributed wireless network such as flexible simulcast, automatic traffic load-balancing, network and radio resource optimization, network calibration, autonomous/assisted commissioning, carrier pooling, automatic frequency selection, frequency carrier placement, traffic monitoring, traffic tagging, pilot beacon, etc.
    Type: Application
    Filed: January 31, 2014
    Publication date: September 25, 2014
    Applicant: DALI SYSTEMS CO. LTD
    Inventors: Paul LEMSON, Shawn Patrick Stapleton, Sasa Trajkovic, Albert S. Lee
  • Patent number: 8824595
    Abstract: A remote radio head unit (RRU) system is disclosed. The present invention is based on the method of adaptive digital predistortion to linearize a power amplifier inside the RRU. The power amplifier characteristics such as variation of linearity and asymmetric distortion of the amplifier output signal are monitored by a wideband feedback path and controlled by the adaptation algorithm in a digital module. Therefore, embodiments of the present invention can compensate for the nonlinearities as well as memory effects of the power amplifier systems and also improve performance, in terms of power added efficiency, adjacent channel leakage ratio and peak-to-average power ratio. The present disclosure enables a power amplifier system to be field reconfigurable and support multi-modulation schemes (modulation agnostic), multi-carriers, multi-frequency bands and multi-channels.
    Type: Grant
    Filed: September 6, 2013
    Date of Patent: September 2, 2014
    Assignee: Dali Systems Co. Ltd.
    Inventors: Wan-Jong Kim, Kyoung-Joon Cho, Shawn Patrick Stapleton, Ying Xiao
  • Publication number: 20140241461
    Abstract: A digital predistortion linearization method is provided for increasing the instantaneous or operational bandwidth for RF power amplifiers employed in wideband communication systems. Embodiments of the present invention provide a method of increasing DPD linearization bandwidth using a feedback filter integrated into existing digital platforms for multi-channel wideband wireless transmitters. An embodiment of the present invention utilizes a DPD feedback signal in conjunction with a low power band-pass filter in the DPD feedback path.
    Type: Application
    Filed: February 26, 2013
    Publication date: August 28, 2014
    Applicant: DALI SYSTEMS CO. LTD.
    Inventors: Wan-Jong Kim, Shawn Patrick Stapleton
  • Patent number: 8817848
    Abstract: A distributed antenna system includes a master unit including a downlink RF input operable to receive an RF input signal from a downlink port of a base station, a first optical port, and a second optical port. The distributed antenna system also includes a first remote unit coupled to the first optical port. The first remote unit comprises a downlink antenna port and a first uplink antenna port and a second remote unit coupled to the second optical port of the master unit. The second remote unit comprises a downlink antenna port and a second uplink antenna port. The master unit is operable to transmit a first RF signal associated with the first RF uplink signal to a first uplink port of the base station and transmit a second RF signal associated with the second RF uplink signal to a second uplink port of the base station.
    Type: Grant
    Filed: September 4, 2012
    Date of Patent: August 26, 2014
    Assignee: Dali Systems Co. Ltd.
    Inventors: Paul Lemson, Shawn Patrick Stapleton, Sasa Trajkovic
  • Publication number: 20140233468
    Abstract: A method for routing and switching operator RF signals includes providing one or more Digital Remote Units (DRUs) and providing at least one Digital Access Unit (DAU) configured to communicate with at least one of the one or more DRUs. A first DRU is operable to communicate using a first set of frequencies characterized by a first frequency band over a first geographic footprint and a second set of frequencies characterized by a second frequency band different from the first frequency band over a second geographic footprint including and surrounding the first geographic footprint. A second DRU is operable to communicate using the first set of frequencies over a third geographical footprint and a third set of frequencies characterized by a third frequency band different from the first frequency band and the second frequency band over a fourth geographic footprint including and surrounding the third geographic footprint.
    Type: Application
    Filed: May 14, 2013
    Publication date: August 21, 2014
    Applicant: DALI SYSTEMS CO. LTD.
    Inventors: Seyed Amin Hejazi, Shawn Patrick Stapleton
  • Patent number: 8811917
    Abstract: A RF-digital hybrid mode power amplifier system for achieving high efficiency and high linearity in wideband communication systems is disclosed. The present invention is based on the method of adaptive digital predistortion to linearize a power amplifier in the RF domain. The power amplifier characteristics such as variation of linearity and asymmetric distortion of the amplifier output signal are monitored by the narrowband feedback path and controlled by the adaptation algorithm in a digital module. Therefore, the present invention could compensate the nonlinearities as well as memory effects of the power amplifier systems and also improve performances, in terms of power added efficiency, adjacent channel leakage ratio and peak-to-average power ratio. The present disclosure enables a power amplifier system to be field reconfigurable and support multi-modulation schemes (modulation agnostic), multi-carriers and multi-channels.
    Type: Grant
    Filed: April 23, 2008
    Date of Patent: August 19, 2014
    Assignee: Dali Systems Co. Ltd.
    Inventors: Wan Jong Kim, Kyoung Joon Cho, Shawn Patrick Stapleton, Jong Heon Kim, Dali Yang
  • Patent number: 8804870
    Abstract: A RF-digital hybrid mode power amplifier system for achieving high efficiency and high linearity in wideband communication systems is disclosed. The present invention is based on the method of adaptive digital predistortion to linearize a power amplifier in the RF domain. The present disclosure enables a power amplifier system to be field reconfigurable and support multi-modulation schemes (modulation agnostic), multi-carriers and multi-channels. As a result, the digital hybrid mode power amplifier system is particularly suitable for wireless transmission systems, such as base-stations, repeaters, and indoor signal coverage systems, where baseband I-Q signal information is not readily available.
    Type: Grant
    Filed: December 21, 2010
    Date of Patent: August 12, 2014
    Assignee: Dali Systems Co. Ltd.
    Inventors: Wan Jong Kim, Kyoung Joon Cho, Shawn Patrick Stapleton, Ying Xiao
  • Publication number: 20140223266
    Abstract: A method of conditioning payload data includes providing a processor and receiving a packet comprising payload data, a first error code, and a second error code. The method also includes computing, using the processor, a first recalculated error code and determining a difference between the first error code and the first recalculated error code. The method further includes modifying the payload data in response to determining the difference.
    Type: Application
    Filed: December 3, 2013
    Publication date: August 7, 2014
    Applicant: DALI SYSTEMS CO. LTD.
    Inventors: Qianqi Zhuang, Shawn Patrick Stapleton
  • Publication number: 20140219174
    Abstract: A remote radio head unit (RRU) system for multiple operating frequency bands, multi-channels, driven by a single or more wide band power amplifiers. More specifically, the present invention enables multiple-bands RRU to use fewer power amplifers in order to reduce size and cost of the multi-band RRU. The present invention is based on the method of using duplexers and/or interference cancellation system technique to increase the isolation between the transmitter signal and receiver signal of the RRU.
    Type: Application
    Filed: April 9, 2014
    Publication date: August 7, 2014
    Applicant: Dali Systems Co., Ltd.
    Inventors: Chengxun WANG, Shawn Patrick STAPLETON
  • Publication number: 20140206282
    Abstract: A method for transporting communications signals includes receiving an analog IF signal at a first unit. The analog IF signal includes a first carrier having a first frequency and a first bandwidth and a second carrier having a second frequency different from the first frequency and a second bandwidth. The analog IF signal is converted to a digitally sampled IF signal having the first carrier located in a first Nyquist zone, the second carrier located in a second Nyquist zone, an image of the first carrier located in a third Nyquist zone, and an image of the second carrier located in the third Nyquist zone. The image of the first carrier and the image of the second carrier is transmitted from the first unit to a second unit, where the image of the first carrier and the image of the second carrier is then converted to the analog IF signal.
    Type: Application
    Filed: March 26, 2014
    Publication date: July 24, 2014
    Applicant: DALI SYSTEMS CO., LTD.
    Inventors: Shawn Patrick Stapleton, Wan-Jong Kim
  • Publication number: 20140191805
    Abstract: A power amplifier using N-way Doherty structure with adaptive bias supply power tracking for extending the efficiency region over the high peak-to-average power:ratio of the multiplexing modulated signals such as wideband code division multiple access and orthogonal frequency division multiplexing is disclosed. In an embodiment, present invention uses a dual-feed distributed structure to an N-way Doherty amplifier to improve the isolation between at least one main amplifier and at least one peaking amplifier and, and also to improve both gain and efficiency performance at high output back-off power. Hybrid couplers can be used at either or both of the input and output. In at least some implementations, circuit space is also conserved due to the integration of amplification, power splitting and combining.
    Type: Application
    Filed: November 22, 2013
    Publication date: July 10, 2014
    Applicant: Dali Systems Co., Ltd.
    Inventors: Kyoung Joon Cho, Wan Jong Kim, Shawn Patrick Stapleton
  • Publication number: 20140179248
    Abstract: A predistortion system for linearizing the output of a power amplifier includes a first signal representative of an RF modulated signal and a feedback signal representative of nonlinear characteristics of a power amplifier. The system also includes a predistortion controller, comprising at least one lookup table, adapted to receive the first signal and the feedback signal and to generate a correction factor for correcting the nonlinear characteristics of the power amplifier and combining logic which combines the RF modulated signal with a signal corresponding to the correction factor and supplies it to the power amplifier to linearize the output of the power amplifier.
    Type: Application
    Filed: December 3, 2013
    Publication date: June 26, 2014
    Applicant: DALI SYSTEMS CO. LTD.
    Inventors: Dali Yang, Jia Yang
  • Publication number: 20140169263
    Abstract: Embodiments may allow remote base transceiver stations (BTSs) physically located away from a local source of users to be able to provide local service as if the remote BTSs were at or near the local source of users. Some embodiments may include a plurality of BTSs, each having one or more sectors, and one or more digital access units (DAUs). Embodiments may also include a plurality of repeater digital units (RDUs), where each RDU may be configured to communicate to at least one of the plurality of BTSs and may be operable to route signals optically to the one or more DAUs. Embodiments may also include a plurality of digital remote units (DRUs) located at a location remote to the one or more DAUs, wherein the plurality of remote DRUs may be operable to transport signals to the one or more DAUs.
    Type: Application
    Filed: October 2, 2013
    Publication date: June 19, 2014
    Applicant: Dali Systems Co. Ltd.
    Inventor: Shawn Patrick Stapleton
  • Publication number: 20140162664
    Abstract: A system for dynamically routing signals in a Distributed Antenna System includes a plurality of Digital Access Units (DAUs). The plurality of DAUs are coupled and operable to route signals between the plurality of DAUs. The system also includes a plurality of Digital Remote Units (DRUs) coupled to the plurality of DAUs and operable to transport signals between DRUs and DAUs and a plurality of Base Transceiver Stations (BTS). The system further includes a plurality of traffic monitoring modules and a network optimization goal and optimization algorithm.
    Type: Application
    Filed: July 24, 2013
    Publication date: June 12, 2014
    Applicant: DALI SYSTEMS CO. LTD.
    Inventors: Shawn Patrick Stapleton, Seyed Amin Hejazi
  • Publication number: 20140162713
    Abstract: A system for routing signals in a Distributed Antenna System includes a plurality of Digital Access Units (DAUs) and a plurality of Digital Remote Units (DRUs). The plurality of DAUs are coupled and operable to route signals between the plurality of DAUs. The plurality of DRUs are coupled to the plurality of DAUs and operable to transport signals between DRUs and DAUs. The system also includes a plurality of Base Transceiver Stations (BTS) and a plurality of Base Transceiver Station sector RF connections coupled to the plurality of DAUs and operable to route signals between the plurality of DAUs and the plurality of Base Transceiver Stations sector RF port connections.
    Type: Application
    Filed: August 6, 2013
    Publication date: June 12, 2014
    Applicant: DALI SYSTEMS CO. LTD.
    Inventors: Shawn Patrick Stapleton, Qianqi Zhang
  • Patent number: 8737300
    Abstract: The present disclosure is a novel utility of a software defined radio (SDR) based Distributed Antenna System (DAS) that is field reconfigurable and support multi-modulation schemes (modulation-independent), multi-carriers, multi-frequency bands and multi-channels. More specifically, the present invention relates to a DAS utilizing one or more Daisy-Chained Rings of Remote Units. The present invention enables a high degree of flexibility to manage, control, enhance, facilitate the usage and performance of a distributed wireless network such as Flexible Simulcast, automatic traffic load-balancing, network and radio resource optimization, network calibration, autonomous/assisted commissioning, carrier pooling, automatic frequency selection, frequency carrier placement, traffic monitoring, traffic tagging, pilot beacon, etc. As a result, a DAS in accordance with the present invention can increase the efficiency and traffic capacity of the operators' wireless network.
    Type: Grant
    Filed: August 16, 2011
    Date of Patent: May 27, 2014
    Assignee: Dali Systems Co. Ltd.
    Inventors: Shawn Patrick Stapleton, Paul Lemson, Bin Lin, Albert S. Lee
  • Patent number: 8730786
    Abstract: A remote radio head unit (RRU) system for multiple operating frequency bands, multi-channels, driven by a single or more wide band power amplifiers. More specifically, the present invention enables multiple-bands RRU to use fewer power amplifiers in order to reduce size and cost of the multi-band RRU. The present invention is based on the method of using duplexers and/or interference cancellation system technique to increase the isolation between the transmitter signal and receiver signal of the RRU.
    Type: Grant
    Filed: December 21, 2010
    Date of Patent: May 20, 2014
    Assignee: Dali Systems Co. Ltd.
    Inventors: Chengxun Wang, Shawn Patrick Stapleton