Patents by Inventor Sheng-Kwang Hwang
Sheng-Kwang Hwang 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: 10461418Abstract: A photonic microwave time delay apparatus and method thereof are disclosed. The microwave-modulated optical signal generation module of the photonic microwave time delay apparatus generates a microwave-modulated optical signal. The microwave-modulated optical signal is injected into the photonic microwave time delay module of the photonic microwave time delay apparatus, wherein the photonic microwave time delay module includes a microwave-time-delay laser. The optical power and carrier frequency of the microwave-modulated optical signal are adjusted so as to excite the laser cavity resonance red-shift effect in the microwave-time-delay laser. Under such operation, the microwave-time-delay laser emits a microwave-modulated optical signal with a microwave time delay.Type: GrantFiled: September 26, 2017Date of Patent: October 29, 2019Assignee: National Cheng Kung UniversityInventors: Sheng-Kwang Hwang, Kun-Lin Hsieh, Chin-Lung Yang
-
Patent number: 10116395Abstract: A photonic microwave mixing apparatus and method thereof are disclosed. An optical input carrying a frequency-to-be-converted microwave signal is injected into a photonic microwave mixing module of the photonic microwave mixing apparatus, wherein the photonic microwave mixing module includes a microwave mixing laser. The optical power and carrier frequency of the optical input are adjusted so as to place the microwave mixing laser in period-one nonlinear dynamics, and, at the same time, to achieve frequency-unlocking between the oscillation sidebands of the period-one nonlinear dynamics and the modulation sidebands of the optical input. Under such operation, the microwave mixing laser emits a nonlinear wave-mixing optical signal. Properly selecting the frequency components of the nonlinear wave-mixing optical signal through an optical frequency component selector generates an optical output carrying a frequency-converted microwave signal, therefore achieving microwave frequency conversion.Type: GrantFiled: February 14, 2017Date of Patent: October 30, 2018Assignee: National Chung Cheng UniversityInventors: Sheng-Kwang Hwang, Yu-Han Hung
-
Publication number: 20180277949Abstract: A photonic microwave time delay apparatus and method thereof are disclosed. The microwave-modulated optical signal generation module of the photonic microwave time delay apparatus generates a microwave-modulated optical signal. The microwave-modulated optical signal is injected into the photonic microwave time delay module of the photonic microwave time delay apparatus, wherein the photonic microwave time delay module includes a microwave-time-delay laser. The optical power and carrier frequency of the microwave-modulated optical signal are adjusted so as to excite the laser cavity resonance red-shift effect in the microwave-time-delay laser. Under such operation, the microwave-time-delay laser emits a microwave-modulated optical signal with a microwave time delay.Type: ApplicationFiled: September 26, 2017Publication date: September 27, 2018Inventors: Sheng-Kwang Hwang, Kun-Lin Hsieh, Chin-Lung Yang
-
Publication number: 20180048393Abstract: A photonic microwave mixing apparatus and method thereof are disclosed. An optical input carrying a frequency-to-be-converted microwave signal is injected into a photonic microwave mixing module of the photonic microwave mixing apparatus, wherein the photonic microwave mixing module includes a microwave mixing laser. The optical power and carrier frequency of the optical input are adjusted so as to place the microwave mixing laser in period-one nonlinear dynamics, and, at the same time, to achieve frequency-unlocking between the oscillation sidebands of the period-one nonlinear dynamics and the modulation sidebands of the optical input. Under such operation, the microwave mixing laser emits a nonlinear wave-mixing optical signal. Properly selecting the frequency components of the nonlinear wave-mixing optical signal through an optical frequency component selector generates an optical output carrying a frequency-converted microwave signal, therefore achieving microwave frequency conversion.Type: ApplicationFiled: February 14, 2017Publication date: February 15, 2018Inventors: SHENG-KWANG HWANG, YU-HAN HUNG
-
Patent number: 9857661Abstract: A photonic microwave generation apparatus and a method thereof are disclosed. A comb-like optical signal generation module of the photonic microwave generation apparatus generates a comb-like optical signal. The comb-like optical signal is injected into a photonic microwave generation module of the photonic microwave generation apparatus, wherein the photonic microwave generation module includes a microwave generation laser. An optical power and a carrier frequency of the comb-like optical signal are adjusted so as to place the microwave generation laser in period-one nonlinear dynamics, and, at the same time, to phase-lock an oscillation sideband of the period-one nonlinear dynamics by one harmonic of the comb-like optical signal. Under such operation, the microwave generation laser emits an output optical signal that carries a microwave signal of a narrow linewidth and a stable frequency, which can be retrieved from the output optical signal by using a photodetector.Type: GrantFiled: February 29, 2016Date of Patent: January 2, 2018Assignee: National Cheng Kung UniversityInventors: Sheng-Kwang Hwang, Yu-Han Hung
-
Publication number: 20170059962Abstract: A photonic microwave generation apparatus and a method thereof are disclosed. A comb-like optical signal generation module of the photonic microwave generation apparatus generates a comb-like optical signal. The comb-like optical signal is injected into a photonic microwave generation module of the photonic microwave generation apparatus, wherein the photonic microwave generation module includes a microwave generation laser. An optical power and a carrier frequency of the comb-like optical signal are adjusted so as to place the microwave generation laser in period-one nonlinear dynamics, and, at the same time, to phase-lock an oscillation sideband of the period-one nonlinear dynamics by one harmonic of the comb-like optical signal. Under such operation, the microwave generation laser emits an output optical signal that carries a microwave signal of a narrow linewidth and a stable frequency, which can be retrieved from the output optical signal by using a photodetector.Type: ApplicationFiled: February 29, 2016Publication date: March 2, 2017Inventors: SHENG-KWANG HWANG, YU-HAN HUNG
-
Patent number: 9473247Abstract: The present invention relates to a device and a method for conversion from optical double-sideband modulation signals to optical single-sideband modulation signals. Period-one nonlinear dynamics of semiconductor lasers is utilized to achieve such optical signal conversion. Only a typical semiconductor laser is required as the key conversion unit. The microwave and data quality are maintained or even improved after conversion, increasing detection sensitivity, transmission distance, and link gain of the communication networks. The device is relatively less sensitive to ambient variations, can be self-adapted to changes in operating conditions, and can be applied for a broad range of operating microwave frequency up to at least 80 GHz and a high data rate up to at least 2.5 Gbits/s. The device can therefore be dynamically reconfigured for different communication networks adopting different operating microwave frequencies and different data rates.Type: GrantFiled: April 30, 2014Date of Patent: October 18, 2016Assignee: NATIONAL CHENG KUNG UNIVERSITYInventors: Sheng-Kwang Hwang, Yu-Han Hung, Cheng-Hao Chu
-
Publication number: 20150280830Abstract: The present invention relates to a device and a method for conversion from optical double-sideband modulation signals to optical single-sideband modulation signals. Period-one nonlinear dynamics of semiconductor lasers is utilized to achieve such optical signal conversion. Only a typical semiconductor laser is required as the key conversion unit. The microwave and data quality are maintained or even improved after conversion, increasing detection sensitivity, transmission distance, and link gain of the communication networks. The device is relatively less sensitive to ambient variations, can be self-adapted to changes in operating conditions, and can be applied for a broad range of operating microwave frequency up to at least 80 GHz and a high data rate up to at least 2.5 Gbits/s. The device can therefore be dynamically reconfigured for different communication networks adopting different operating microwave frequencies and different data rates.Type: ApplicationFiled: April 30, 2014Publication date: October 1, 2015Applicant: NATIONAL CHENG KUNG UNIVERSITYInventors: Sheng-Kwang Hwang, Yu-Han Hung, Cheng-Hao Chu
-
Patent number: 9143094Abstract: Period-one nonlinear dynamics of semiconductor lasers are utilized to provide an apparatus for photonic microwave power amplification in radio-over-fiber links through optical modulation depth improvement. The microwave power amplification apparatus includes a microwave-modulated optical signal generation module and a microwave power amplification module. The amplification capability of the present microwave power amplification apparatus covers a broad microwave range, from less than 25 GHz to more than 60 GHz, and a wide gain range, from less than 10 dB to more than 30 dB. The microwave phase quality is mainly preserved while the microwave power is largely amplified, improving the signal-to-noise ratio up to at least 25 dB. The bit-error ratio at 1.25 Gb/s is better than 10?9 and a sensitivity improvement of up to at least 15 dB is feasible.Type: GrantFiled: August 26, 2014Date of Patent: September 22, 2015Assignee: NATIONAL CHENG KUNG UNIVERSITYInventors: Sheng-Kwang Hwang, Yu-Han Hung
-
Publication number: 20150244331Abstract: Period-one nonlinear dynamics of semiconductor lasers are utilized to provide an apparatus for photonic microwave power amplification in radio-over-fiber links through optical modulation depth improvement. The microwave power amplification apparatus includes a microwave-modulated optical signal generation module and a microwave power amplification module. The amplification capability of the present microwave power amplification apparatus covers a broad microwave range, from less than 25 GHz to more than 60 GHz, and a wide gain range, from less than 10 dB to more than 30 dB. The microwave phase quality is mainly preserved while the microwave power is largely amplified, improving the signal-to-noise ratio up to at least 25 dB. The bit-error ratio at 1.25 Gb/s is better than 10?9 and a sensitivity improvement of up to at least 15 dB is feasible.Type: ApplicationFiled: August 26, 2014Publication date: August 27, 2015Inventors: Sheng-Kwang HWANG, Yu-Han HUNG
-
Patent number: 8861969Abstract: A laser source is configured for all-optical AM-FM up-conversion. In one exemplary embodiment, an amplitude modulated (AM) optical input signal containing a baseband signal at a sub-microwave frequency, is injected into the laser source. The amplitude of the AM optical input signal and the optical carrier frequency are adjusted so as to place the laser source in a period-one dynamical state characterized by a transitioning of the laser source from a free-running optical frequency to at least two optical frequencies having a separation distance equal to a period-one microwave frequency. As a result of the period-one dynamical state, a frequency modulated (FM) optical output signal containing the baseband signal carried at the period-one microwave frequency, is propagated out of the laser source. The period-one microwave frequency is operative as a sub-carrier signal.Type: GrantFiled: August 13, 2007Date of Patent: October 14, 2014Assignee: The Regents of the University of CaliforniaInventors: Sze-Chun Chan, Sheng-Kwang Hwang, Jia-Ming Liu
-
Publication number: 20110044692Abstract: A laser source is configured for all-optical AM-FM up-conversion. In one exemplary embodiment, an amplitude modulated (AM) optical input signal containing a baseband signal at a sub-microwave frequency, is injected into the laser source. The amplitude of the AM optical input signal and the optical carrier frequency are adjusted so as to place the laser source in a period-one dynamical state characterized by a transitioning of the laser source from a free-running optical frequency to at least two optical frequencies having a separation distance equal to a period-one microwave frequency. As a result of the period-one dynamical state, a frequency modulated (FM) optical output signal containing the baseband signal carried at the period-one microwave frequency, is propagated out of the laser source. The period-one microwave frequency is operative as a sub-carrier signal.Type: ApplicationFiled: August 13, 2007Publication date: February 24, 2011Inventors: Sze-Chun Chan, Sheng-Kwang Hwang, Jia-Ming Liu