Patents by Inventor Dali Yang
Dali Yang 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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Publication number: 20150333710Abstract: 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: ApplicationFiled: April 20, 2015Publication date: November 19, 2015Inventors: Dali Yang, Jia Yang
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Publication number: 20150326349Abstract: A power amplifier system includes an input operable to receive an original value that reflects information to be communicated and an address data former operable to generate a digital lookup table key. The power amplifier system also includes a predistortion lookup table coupled to the address data former and a power amplifier having an output and coupled to the predistortion lookup table. The power amplifier system further includes a feedback loop providing a signal associated with the output of the power amplifier to the predistortion lookup table and a switch disposed in the feedback loop and operable to disconnect the predistortion lookup table from the output of the power amplifier.Type: ApplicationFiled: April 13, 2015Publication date: November 12, 2015Inventors: Dali YANG, Jia Yang
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Patent number: 9077297Abstract: An embodiment of the invention is a time-delay invariant predistortion approach to linearize power amplifiers in wireless RF transmitters. The predistortion architecture is based on the stored-compensation or memory-compensation principle by using a combined time-delay addressing method, and therefore, the architecture has an intrinsic, self-calibrating time-delay compensation function. The predistortion architecture only uses a lookup table to conduct both the correction of non-linear responses of a power amplifier and the compensation of any time-delay effects presented in the same system. Due to the time-delay invariant characteristic, the predistortion design has a wider dynamic range processing advantage for wireless RF signals, and therefore can be implemented in multi-carrier and multi-channel wireless systems.Type: GrantFiled: December 21, 2012Date of Patent: July 7, 2015Assignee: DALI SYSTEMS CO., LTD.Inventors: Dali Yang, Jia Yang
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Patent number: 9054758Abstract: 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: GrantFiled: December 3, 2013Date of Patent: June 9, 2015Assignee: DALI SYSTEMS CO. LTD.Inventors: Dali Yang, Jia Yang
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Patent number: 9031521Abstract: A power amplifier system includes an input operable to receive an original value that reflects information to be communicated and an address data former operable to generate a digital lookup table key. The power amplifier system also includes a predistortion lookup table coupled to the address data former and a power amplifier having an output and coupled to the predistortion lookup table. The power amplifier system further includes a feedback loop providing a signal associated with the output of the power amplifier to the predistortion lookup table and a switch disposed in the feedback loop and operable to disconnect the predistortion lookup table from the output of the power amplifier.Type: GrantFiled: April 4, 2014Date of Patent: May 12, 2015Assignee: Dali Systems Co. Ltd.Inventors: Dali Yang, Jia Yang
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Publication number: 20140327481Abstract: 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: ApplicationFiled: May 7, 2014Publication date: November 6, 2014Applicant: DALI SYSTEMS CO., LTD.Inventors: Wan Jong Kim, Kyoung Joon Cho, Shawn Patrick Stapleton, Jong Heon Kim, Dali Yang
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Publication number: 20140306762Abstract: A power amplifier system includes an input operable to receive an original value that reflects information to be communicated and an address data former operable to generate a digital lookup table key. The power amplifier system also includes a predistortion lookup table coupled to the address data former and a power amplifier having an output and coupled to the predistortion lookup table. The power amplifier system further includes a feedback loop providing a signal associated with the output of the power amplifier to the predistortion lookup table and a switch disposed in the feedback loop and operable to disconnect the predistortion lookup table from the output of the power amplifier.Type: ApplicationFiled: April 4, 2014Publication date: October 16, 2014Applicant: DALI SYSTEMS CO. LTD.Inventors: Dali Yang, Jia Yang
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Patent number: 8811917Abstract: 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: GrantFiled: April 23, 2008Date of Patent: August 19, 2014Assignee: Dali Systems Co. Ltd.Inventors: Wan Jong Kim, Kyoung Joon Cho, Shawn Patrick Stapleton, Jong Heon Kim, Dali Yang
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Publication number: 20140179248Abstract: 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: ApplicationFiled: December 3, 2013Publication date: June 26, 2014Applicant: DALI SYSTEMS CO. LTD.Inventors: Dali Yang, Jia Yang
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Patent number: 8731495Abstract: An embodiment of the invention is a system for signal processing in preparation for wireless transmission, the wireless transmission being from a portable wireless communication device and including use of a power amplifier having nonlinear characteristics. The system includes memory for storing digitally-indexed information. The digitally-indexed information models nonlinear characteristics of the power amplifier, and the digitally-indexed information is stored prior to processing of a first signal that reflects information to be communicated. The system further includes first logic, configured to accept the first signal and to retrieve, based on the first signal, a portion of the digitally-indexed information stored in the memory, and second logic, configured to generate a second signal based on the portion of the digitally-accessed information and on the first signal.Type: GrantFiled: September 14, 2012Date of Patent: May 20, 2014Assignee: Dali Systems Co. Ltd.Inventors: Dali Yang, Jia Yang
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Patent number: 8693962Abstract: An embodiment of the invention is a predistortion approach to linearize a power amplifier by using one or more analog multiplier(s) and a DSP-based processor. For the analog embodiment, the inherent nature of the analog circuitries allows digital predistortion processing structured directly at the RF band, and enables a single power amplifier to support multi-modulation schemes, multi-carriers and multi-channels. As a result, the predistortion architecture is particularly suitable for wireless transmission systems, such as base-stations, repeaters, and indoor signal coverage systems. The wireless system performance can be improved and upgraded just by using the new PA module rather than change or rebuild new subsystem in existing base station. The analog embodiment can also mix and match its analog multipliers with other analog components such as phase splitters, phase shifters, attenuators, filters, couplers, mixers, low-noise amplifiers, buffers, envelope detectors, and etc., to provide additional features.Type: GrantFiled: September 2, 2008Date of Patent: April 8, 2014Assignee: Dali Systems Co. Ltd.Inventors: Dongtai Liu, Dali Yang, James Anderson
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Patent number: 8620234Abstract: 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: GrantFiled: November 21, 2011Date of Patent: December 31, 2013Assignee: Dali Systems Co., Ltd.Inventors: Dali Yang, Jia Yang
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Publication number: 20130243124Abstract: An embodiment of the invention is a system for signal processing in preparation for wireless transmission, the wireless transmission being from a portable wireless communication device and including use of a power amplifier having nonlinear characteristics. The system includes memory for storing digitally-indexed information. The digitally-indexed information models nonlinear characteristics of the power amplifier, and the digitally-indexed information is stored prior to processing of a first signal that reflects information to be communicated. The system further includes first logic, configured to accept the first signal and to retrieve, based on the first signal, a portion of the digitally-indexed information stored in the memory, and second logic, configured to generate a second signal based on the portion of the digitally-accessed information and on the first signal.Type: ApplicationFiled: September 14, 2012Publication date: September 19, 2013Applicant: DALI SYSTEMS CO. LTD.Inventors: Dali Yang, Jia Yang
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Patent number: 8472897Abstract: An embodiment of the invention is a predistortion approach to linearize a power amplifier by setting initially the static operation point of the power amplifier in the cut-off region. The architecture is based on the analog-digital combination by a multiplier and digital predistortion control circuit. The predistortion system generates an adaptive output signal to control the RF modulated signal that is the input signal of the power amplifier. The controlled and predistorted signal can contribute to drive a power amplifier with the cut-off static operation point into its amplifying region and simultaneously correct the non-linear distortion when the power amplifier operates to amplify an RF signal.Type: GrantFiled: December 20, 2007Date of Patent: June 25, 2013Assignee: Dali Systems Co. Ltd.Inventor: Dali Yang
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Patent number: 8425822Abstract: A composition of matter suitable for spinning polyaniline fiber, a method for spinning electrically conductive polyaniline fiber, a method for exchanging dopants in polyaniline fibers, and methods for dedoping and redoping polyaniline fibers are described.Type: GrantFiled: February 28, 2011Date of Patent: April 23, 2013Assignee: Santa Fe Science and Technology, Inc.Inventors: Benjamin R. Mattes, Phillip N. Adams, Dali Yang, Lori A. Brown, Andrei G. Fadeev, Ian D. Norris
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Patent number: 8380143Abstract: An embodiment of the invention is a time-delay invariant predistortion approach to linearize power amplifiers in wireless RF transmitters. The predistortion architecture is based on the stored-compensation or memory-compensation principle by using a combined time-delay addressing method, and therefore, the architecture has an intrinsic, self-calibrating time-delay compensation function. The predistortion architecture only uses a lookup table to conduct both the correction of non-linear responses of a power amplifier and the compensation of any time-delay effects presented in the same system. Due to the time-delay invariant characteristic, the predistortion design has a wider dynamic range processing advantage for wireless RF signals, and therefore can be implemented in multi-carrier and multi-channel wireless systems.Type: GrantFiled: January 28, 2008Date of Patent: February 19, 2013Assignee: Dali Systems Co. LtdInventors: Dali Yang, Jia Yang
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Patent number: 8326238Abstract: An embodiment of the invention is a system for signal processing in preparation for wireless transmission, the wireless transmission being from a portable wireless communication device and including use of a power amplifier having nonlinear characteristics. The system includes memory for storing digitally-indexed information. The digitally-indexed information models nonlinear characteristics of the power amplifier, and the digitally-indexed information is stored prior to processing of a first signal that reflects information to be communicated. The system further includes first logic, configured to accept the first signal and to retrieve, based on the first signal, a portion of the digitally-indexed information stored in the memory, and second logic, configured to generate a second signal based on the portion of the digitally-accessed information and on the first signal.Type: GrantFiled: October 27, 2005Date of Patent: December 4, 2012Assignee: Dali Systems Co, Ltd.Inventors: Dali Yang, Jia Yang
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Patent number: 8224266Abstract: An embodiment of the invention is a predistortion approach to linearize a power amplifier without frequency conversion of the RF signals by using envelope and phase detectors to detect the error to be corrected, and then one or more analog multiplier(s) and a DSP-based processor. For the analog embodiment, the inherent nature of the analog circuitries allows digital predistortion processing structured directly at the RF band, and enables a single power amplifier to support multi-modulation schemes, multi-carriers and multi-channels. As a result, the predistortion architecture is particularly suitable for wireless transmission systems, such as base-stations, repeaters, and indoor signal coverage systems. The wireless system performance can be improved and upgraded just by using the new PA module rather than change or rebuild new subsystem in existing base station.Type: GrantFiled: September 2, 2008Date of Patent: July 17, 2012Assignee: Dali Systems Co., Ltd.Inventors: Dongtai Liu, Dali Yang, James Anderson
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Publication number: 20120135695Abstract: 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: ApplicationFiled: November 21, 2011Publication date: May 31, 2012Applicant: Dali Systems Co., Ltd.Inventors: Dali Yang, Jia Yang
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Patent number: 8066852Abstract: Light hydrocarbon enrichment is accomplished using a vertically oriented distillation column having a plurality of vertically oriented, nonselective micro/mesoporous hollow fibers. Vapor having, for example, both propylene and propane is sent upward through the distillation column in between the hollow fibers. Vapor exits neat the top of the column and is condensed to form a liquid phase that is directed back downward through the lumen of the hollow fibers. As vapor continues to ascend and liquid continues to countercurrently descend, the liquid at the bottom of the column becomes enriched in a higher boiling point, light hydrocarbon (propane, for example) and the vapor at the top becomes enriched in a lower boiling point light hydrocarbon (propylene, for example). The hollow fiber becomes wetted with liquid during the process.Type: GrantFiled: June 30, 2010Date of Patent: November 29, 2011Assignee: Los Alamos National Security, LLCInventors: Dali Yang, David Devlin, Robert S. Barbero, Martin E. Carrera, Craig W. Colling