Patents by Inventor Fa Dai
Fa Dai 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: 20230387934Abstract: An analog-to-digital converter includes a first converter stage comprising a successive-approximation-register (SAR) analog-to-digital converter (ADC), the SAR ADC being configured for voltage domain quantization, a second converter stage coupled to the first converter stage to quantize residual voltages of the voltage domain quantization, the second converter stage including a ring time-to-digital converter (TDC), and a third converter stage comprising an interpolation TDC, the interpolation TDC being coupled to the second converter stage to provide further time domain quantization.Type: ApplicationFiled: May 24, 2022Publication date: November 30, 2023Inventors: Haoyi Zhao, Fa Dai, John David Irwin
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Patent number: 11784653Abstract: An analog-to-digital converter includes a first converter stage, a second converter stage coupled to the first converter stage to quantize a residue signal of the first converter stage, and an inter-stage converter disposed between the first and second converter stages. The inter-stage converter is configured to convert between a first domain and a second domain. The inter-stage converter is configured to process the residue signal of the first converter stage such that a range of the residue signal matches a full scale of the second converter stage.Type: GrantFiled: October 28, 2021Date of Patent: October 10, 2023Assignee: Digital Analog Integration, Inc.Inventors: Haoyi Zhao, Fa Dai, John David Irwin
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Publication number: 20220255553Abstract: An analog-to-digital converter includes a first converter stage, a second converter stage coupled to the first converter stage to quantize a residue signal of the first converter stage, and an inter-stage converter disposed between the first and second converter stages. The inter-stage converter is configured to convert between a first domain and a second domain. The inter-stage converter is configured to process the residue signal of the first converter stage such that a range of the residue signal matches a full scale of the second converter stage.Type: ApplicationFiled: October 28, 2021Publication date: August 11, 2022Inventors: Haoyi Zhao, Fa Dai, John David Irwin
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Patent number: 11239853Abstract: An analog-to-digital converter includes a first converter stage, a second converter stage coupled to the first converter stage to quantize a residue signal of the first converter stage, and an inter-stage converter disposed between the first and second converter stages. The inter-stage converter is configured to convert between a first domain and a second domain. The inter-stage converter is configured to process the residue signal of the first converter stage such that a range of the residue signal matches a full scale of the second converter stage.Type: GrantFiled: October 28, 2020Date of Patent: February 1, 2022Assignee: Digital Analog Integration, Inc.Inventors: Fa Dai, Haoyi Zhao, John David Irwin
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Patent number: 11206163Abstract: The present disclosure includes a time-to-digital converter (TDC) based RF-to-digital (RDC) data converter for time domain signal processing polar receivers. Polar data conversion achieves better SNR tolerance owing to its phase convergence near the origin in a polar coordinate. The proposed RDC consists of a TDC for phase detection and an analog-to-digital converter (ADC) for amplitude conversion. Unlike the conversional data converter, the proposed ADC's sampling position is guided by the detected phase result from the TDC's output. This TDC assisted data-converter architecture reduces the number of bits required for the ADC. In addition, oversampling is no longer needed. With precisely controlled tunable delay cells and gain compensator, this hybrid data convertor is capable to directly convert Quadrature Amplitude Modulation (QAM) waveforms and Amplitude Phase Shift Keying (APSK) waveforms directly from the RF signal without down-conversion.Type: GrantFiled: March 18, 2021Date of Patent: December 21, 2021Assignee: Auburn UniversityInventors: Fa Dai, Hechen Wang
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Publication number: 20210250213Abstract: The present disclosure includes a time-to-digital converter (TDC) based RF-to-digital (RDC) data converter for time domain signal processing polar receivers. Polar data conversion achieves better SNR tolerance owing to its phase convergence near the origin in a polar coordinate. The proposed RDC consists of a TDC for phase detection and an analog-to-digital converter (ADC) for amplitude conversion. Unlike the conversional data converter, the proposed ADC's sampling position is guided by the detected phase result from the TDC's output. This TDC assisted data-converter architecture reduces the number of bits required for the ADC. In addition, oversampling is no longer needed. With precisely controlled tunable delay cells and gain compensator, this hybrid data convertor is capable to directly convert Quadrature Amplitude Modulation (QAM) waveforms and Amplitude Phase Shift Keying (APSK) waveforms directly from the RF signal without down-conversion.Type: ApplicationFiled: March 18, 2021Publication date: August 12, 2021Applicant: Auburn UniversityInventors: Fa Dai, Hechen Wang
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Patent number: 10958491Abstract: The present disclosure includes a time-to-digital converter (TDC) based RF-to-digital (RDC) data converter for time domain signal processing polar receivers. Polar data conversion achieves better SNR tolerance owing to its phase convergence near the origin in a polar coordinate. The proposed RDC consists of a TDC for phase detection and an analog-to-digital converter (ADC) for amplitude conversion. Unlike the conversional data converter, the proposed ADC's sampling position is guided by the detected phase result from the TDC's output. This TDC assisted data-converter architecture reduces the number of bits required for the ADC. In addition, oversampling is no longer needed. With precisely controlled tunable delay cells and gain compensator, this hybrid data convertor is capable to directly convert Quadrature Amplitude Modulation (QAM) waveforms and Amplitude Phase Shift Keying (APSK) waveforms directly from the RF signal without down-conversion.Type: GrantFiled: July 20, 2020Date of Patent: March 23, 2021Assignee: Auburn UniversityInventors: Fa Dai, Hechen Wang
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Publication number: 20200374165Abstract: The present disclosure includes a time-to-digital converter (TDC) based RF-to-digital (RDC) data converter for time domain signal processing polar receivers. Polar data conversion achieves better SNR tolerance owing to its phase convergence near the origin in a polar coordinate. The proposed RDC consists of a TDC for phase detection and an analog-to-digital converter (ADC) for amplitude conversion. Unlike the conversional data converter, the proposed ADC's sampling position is guided by the detected phase result from the TDC's output. This TDC assisted data-converter architecture reduces the number of bits required for the ADC. In addition, oversampling is no longer needed. With precisely controlled tunable delay cells and gain compensator, this hybrid data convertor is capable to directly convert Quadrature Amplitude Modulation (QAM) waveforms and Amplitude Phase Shift Keying (APSK) waveforms directly from the RF signal without down-conversion.Type: ApplicationFiled: July 20, 2020Publication date: November 26, 2020Applicant: Auburn UniversityInventors: Fa Dai, Hechen Wang
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Patent number: 10785075Abstract: The present disclosure includes a time-to-digital converter (TDC) based RF-to-digital (RDC) data converter for time domain signal processing polar receivers. Polar data conversion achieves better SNR tolerance owing to its phase convergence near the origin in a polar coordinate. The proposed RDC consists of a TDC for phase detection and an analog-to-digital converter (ADC) for amplitude conversion. Unlike the conversional data converter, the proposed ADC's sampling position is guided by the detected phase result from the TDC's output. This TDC assisted data-converter architecture reduces the number of bits required for the ADC. In addition, oversampling is no longer needed. With precisely controlled tunable delay cells and gain compensator, this hybrid data convertor is capable to directly convert Quadrature Amplitude Modulation (QAM) waveforms and Amplitude Phase Shift Keying (APSK) waveforms directly from the RF signal without down-conversion.Type: GrantFiled: November 13, 2018Date of Patent: September 22, 2020Assignee: Auburn UniversityInventors: Fa Dai, Hechen Wang
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Patent number: 10396807Abstract: The disclosure of the present application presents a multiple-ring coupled ring oscillator design that employs multiple-ring coupling to achieve improved phase noise by minimizing noise injection from tail current and adjacent rings, while providing additional output phases for multiphase signal generation. In one non-limiting exemplary prototype embodiment, a 1.5 GHz triple-ring coupled ring oscillator achieved measured phase noise of ?110.5 dBc/Hz at 1 MHz offset, demonstrating phase noise reduction of 7 dB compared with its single-ring oscillator counterpart. The MROs couple multiple rings with proper phase shifting to achieve improved phase noise. Common source coupling benefits from tail current noise reduction, and introducing phase delays in the coupling paths minimizes noise coupling from the adjacent cores. The overall effect leads to improved phase noise performance as demonstrated in quadrature voltage controlled VCO designs.Type: GrantFiled: November 21, 2017Date of Patent: August 27, 2019Assignee: Auburn UniversityInventors: Fa Dai, Ruixin Wang
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Publication number: 20190149376Abstract: The present disclosure includes a time-to-digital converter (TDC) based RF-to-digital (RDC) data converter for time domain signal processing polar receivers. Polar data conversion achieves better SNR tolerance owing to its phase convergence near the origin in a polar coordinate. The proposed RDC consists of a TDC for phase detection and an analog-to-digital converter (ADC) for amplitude conversion. Unlike the conversional data converter, the proposed ADC's sampling position is guided by the detected phase result from the TDC's output. This TDC assisted data-converter architecture reduces the number of bits required for the ADC. In addition, oversampling is no longer needed. With precisely controlled tunable delay cells and gain compensator, this hybrid data convertor is capable to directly convert Quadrature Amplitude Modulation (QAM) waveforms and Amplitude Phase Shift Keying (APSK) waveforms directly from the RF signal without down-conversion.Type: ApplicationFiled: November 13, 2018Publication date: May 16, 2019Applicant: Auburn UniversityInventors: Fa Dai, Hechen Wang
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Patent number: 10128890Abstract: Some embodiments include a privacy/security apparatus for a portable communication device that includes a housing assembly configured to at least partially attenuate at least one of sound energy, acoustic energy, and electromagnetic energy including light, optical, and IR energy and RF radiation from passing through the housing assembly. The housing assembly includes a Faraday cage with two or more portions, and at least one protective shell coupled to or forming at least one aperture. The at least one aperture is configured and arranged to at least partially enclose the portable communication device so that at least a portion of the portable communication device is positioned within at least one portion of the Faraday cage, and the at least one seal coupled or integrated with the protective shell. The housing assembly can be an articulating assembly, a sliding assembly, and can include an active acoustic jamming or passive acoustic attenuation element.Type: GrantFiled: September 9, 2015Date of Patent: November 13, 2018Inventors: Teddy David Thomas, Harald Quintus-Bosz, Manas Chandran Menon, Anthony Clegg Parker, Klaus Heribert Renner, Julien Prosper Marc Aknin, Christopher O. Evans, Bing Xu, Huyen NguyenNgoc Cam Le, Fa Dai, John Stadille, Michael Fong, John Kinnard, Craig Ovans, Andres Parada, John Deros, Andrew Goodfellow, Justin David Cumming, Gregg Robert Draudt, Eric Smallwood, Piotr Diduch, Christopher R. McCaslin, Elias R. Samia, Evan Hutker, Robert Francis Hartmann, Stuart Eric Schechter
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Patent number: 9985638Abstract: A digitally controlled oscillator (DCO) modulation apparatus and method provides a wideband phase-modulated signal output. An exemplary modulator circuit uses an oscillator in a phase-locked loop. The circuit receives a wrapped-phase input signal, unwraps the wrapped-phase input signal to generate an unwrapped-phase signal, and differentiates the unwrapped-phase signal. The wrapped-phase input signal and the differentiated unwrapped-phase signal are both injected into a feedback loop of the modulator circuit. The feedback loop may include a multi-modulus frequency divider with a frequency divisor that is temporarily incremented or decremented to cancel out abrupt phase jumps associated with the wrapped-phase to unwrapped-phase conversion.Type: GrantFiled: March 24, 2017Date of Patent: May 29, 2018Assignee: Innophase INC.Inventors: Yang Xu, Fa Dai, Dongyi Liao
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Patent number: 9979427Abstract: Some embodiments include a privacy/security apparatus for a portable communication device that includes a housing assembly configured to at least partially attenuate at least one of sound energy, acoustic energy, and electromagnetic energy including light, optical, and IR energy and RF radiation from passing through the housing assembly. The housing assembly includes a Faraday cage with two or more portions, and at least one protective shell coupled to or forming at least one aperture. The at least one aperture is configured and arranged to at least partially enclose the portable communication device so that at least a portion of the portable communication device is positioned within at least one portion of the Faraday cage, and the at least one seal coupled or integrated with the protective shell. The housing assembly can be an articulating assembly, a sliding assembly, and can include an active acoustic jamming or passive acoustic attenuation element.Type: GrantFiled: September 9, 2015Date of Patent: May 22, 2018Inventors: Teddy David Thomas, Harald Quintus-Bosz, Manas Chandran Menon, Anthony Clegg Parker, Klaus Heribert Renner, Julien Prosper Marc Aknin, Christopher O. Evans, Bing Xu, Huyen NguyenNgoc Cam Le, Fa Dai, John Stadille, Michael Fong, John Kinnard, Craig Ovans, Andres Parada, John Deros, Andrew Goodfellow, Justin David Cumming, Gregg Robert Draudt, Eric Smallwood, Piotr Diduch, Christopher R. McCaslin, Elias R. Samia, Evan Hutker, Robert Francis Hartmann, Stuart Eric Schechter
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Publication number: 20170194975Abstract: A digitally controlled oscillator (DCO) modulation apparatus and method provides a wideband phase-modulated signal output. An exemplary modulator circuit uses an oscillator in a phase-locked loop. The circuit receives a wrapped-phase input signal, unwraps the wrapped-phase input signal to generate an unwrapped-phase signal, and differentiates the unwrapped-phase signal. The wrapped-phase input signal and the differentiated unwrapped-phase signal are both injected into a feedback loop of the modulator circuit. The feedback loop may include a multi-modulus frequency divider with a frequency divisor that is temporarily incremented or decremented to cancel out abrupt phase jumps associated with the wrapped-phase to unwrapped-phase conversion.Type: ApplicationFiled: March 24, 2017Publication date: July 6, 2017Inventors: Yang Xu, Fa Dai, Dongyi Liao
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Patent number: 9608648Abstract: A digitally controlled oscillator (DCO) modulation apparatus and method provides a wideband phase-modulated signal output. An exemplary modulator circuit uses an oscillator in a phase-locked loop. The circuit receives a wrapped-phase input signal, unwraps the wrapped-phase input signal to generate an unwrapped-phase signal, and differentiates the unwrapped-phase signal. The wrapped-phase input signal and the differentiated unwrapped-phase signal are both injected into a feedback loop of the modulator circuit. The feedback loop may include a multi-modulus frequency divider with a frequency divisor that is temporarily incremented or decremented to cancel out abrupt phase jumps associated with the wrapped-phase to unwrapped-phase conversion.Type: GrantFiled: July 11, 2016Date of Patent: March 28, 2017Assignee: INNOPHASE, INC.Inventors: Yang Xu, Fa Dai, Dongyi Liao
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Publication number: 20160322980Abstract: A digitally controlled oscillator (DCO) modulation apparatus and method provides a wideband phase-modulated signal output. An exemplary modulator circuit uses an oscillator in a phase-locked loop. The circuit receives a wrapped-phase input signal, unwraps the wrapped-phase input signal to generate an unwrapped-phase signal, and differentiates the unwrapped-phase signal. The wrapped-phase input signal and the differentiated unwrapped-phase signal are both injected into a feedback loop of the modulator circuit. The feedback loop may include a multi-modulus frequency divider with a frequency divisor that is temporarily incremented or decremented to cancel out abrupt phase jumps associated with the wrapped-phase to unwrapped-phase conversion.Type: ApplicationFiled: July 11, 2016Publication date: November 3, 2016Inventors: Yang Xu, Fa Dai, Dongyi Liao
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Publication number: 20160234356Abstract: Some embodiments include a privacy/security apparatus for a portable communication device that includes a housing assembly configured to at least partially attenuate at least one of sound energy, acoustic energy, and electromagnetic energy including light, optical, and IR energy and RF radiation from passing through the housing assembly. The housing assembly includes a Faraday cage with two or more portions, and at least one protective shell coupled to or forming at least one aperture. The at least one aperture is configured and arranged to at least partially enclose the portable communication device so that at least a portion of the portable communication device is positioned within at least one portion of the Faraday cage, and the at least one seal coupled or integrated with the protective shell. The housing assembly can be an articulating assembly, a sliding assembly, and can include an active acoustic jamming or passive acoustic attenuation element.Type: ApplicationFiled: September 9, 2015Publication date: August 11, 2016Inventors: Teddy David Thomas, Harald Quintus-Bosz, Manas Chandran Menon, Anthony Clegg Parker, Klaus Heribert Renner, Julien Prosper Marc Aknin, Christopher O. Evans, Bing Xu, Huyen NguyenNgoc Cam Le, Fa Dai, John Stadille, Michael Fong, John Kinnard, Craig Ovans, Andres Parada, John Deros, Andrew Goodfellow, Justin David Cumming, Gregg Robert Draudt, Eric Smallwood, Piotr Diduch, Christopher R. McCaslin, Elias R. Samia, Evan Hutker, Robert Francis Hartmann, Stuart Eric Schechter
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Publication number: 20160233912Abstract: Some embodiments include a privacy/security apparatus for a portable communication device that includes a housing assembly configured to at least partially attenuate at least one of sound energy, acoustic energy, and electromagnetic energy including light, optical, and IR energy and RF radiation from passing through the housing assembly. The housing assembly includes a Faraday cage with two or more portions, and at least one protective shell coupled to or forming at least one aperture. The at least one aperture is configured and arranged to at least partially enclose the portable communication device so that at least a portion of the portable communication device is positioned within at least one portion of the Faraday cage, and the at least one seal coupled or integrated with the protective shell. The housing assembly can be an articulating assembly, a sliding assembly, and can include an active acoustic jamming or passive acoustic attenuation element.Type: ApplicationFiled: September 9, 2015Publication date: August 11, 2016Inventors: Teddy David Thomas, Harald Quintus-Bosz, Manas Chandran Menon, Anthony Clegg Parker, Klaus Heribert Renner, Julien Prosper Marc Aknin, Christopher O. Evans, Bing Xu, Huyen NguyenNgoc Cam Le, Fa Dai, John Stadille, Michael Fong, John Kinnard, Craig Ovans, Andres Parada, John Deros, Andrew Goodfellow, Justin David Cumming, Gregg Robert Draudt, Eric Smallwood, Piotr Diduch, Christopher R. McCaslin, Elias R. Samia, Evan Hutker, Robert Francis Hartmann, Stuart Eric Schechter
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Patent number: 7577695Abstract: A direct digital synthesis (DDS) circuit utilizes high order delta-sigma interpolators to remove frequency, phase and amplitude domain quantization errors. The DDS employs an n-bit accumulator operative for receiving an input frequency word (FCW) representing the desired frequency output and converts the frequency word to phase information based upon the clock frequency of the DDS. A high-order delta-sigma interpolator is configured in frequency, phase or amplitude domain to noise-shape the quantization errors through a unit defined by the transfer function of 1-(1?z?1)k in either a feedforward or feedback manner. The delta-sigma interpolator of any order can be implemented using a single-stage pipelined topology with noise transfer function of (1?z?1)k. The DDS circuit also includes digital-to-analog converters (DACs) that convert the outputted sine and cosine amplitude words to analog sinusoidal quardrature signals; and deglitch analog low-pass filters that remove the small glitches due to data conversion.Type: GrantFiled: July 22, 2005Date of Patent: August 18, 2009Assignee: Auburn UniversityInventor: Fa Dai