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Jyehong Chen - One of the best experts on this subject based on the ideXlab platform.
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optical filter requirements in an eml based single sideband pam4 Intensity Modulation and direct detection transmission system
Optics Express, 2017Co-Authors: Hsingyu Chen, Noriaki Kaneda, Jyehong Chen, Youngkai ChenAbstract:The feasibility of a single sideband (SSB) PAM4 Intensity-Modulation and direct-detection (IM/DD) transmission based on a CMOS ADC and DAC is experimentally demonstrated in this work. To cost effectively build a >50 Gb/s system as well as to extend the transmission distance, a low cost EML and a passive optical filter are utilized to generate the SSB signal. However, the EML-induced chirp and dispersion-induced power fading limit the requirements of the SSB filter. To separate the effect of signal-signal beating interference, filters with different roll-off factors are employed to demonstrate the performance tolerance at different transmission distance. Moreover, a high resolution spectrum analysis is proposed to depict the system limitation. Experimental results show that a minimum roll-off factor of 7 dB/10GHz is required to achieve a 51.84Gb/s 40-km transmission with only linear feed-forward equalization.
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cost effective 33 gbps Intensity Modulation direct detection multi band ofdm lr pon system employing a 10 ghz based transceiver
Optics Express, 2011Co-Authors: Hsingyu Chen, Wei Yuan Li, Jyehong ChenAbstract:We develop a dynamic multi-band OFDM subcarrier allocation scheme to fully utilize the available bandwidth under the restriction of dispersion- and chirp-related power fading. The experimental results successfully demonstrate an Intensity-Modulation-direct-detection 34.78-Gbps OFDM signal transmissions over 100-km long-reach (LR) passive-optical networks (PONs) based on a cost-effective 10-GHz EAM and a 10-GHz PIN. Considering 0–100-km transmission bandwidth of a 10-GHz EAM, the narrowest bandwidth is theoretically evaluated to occur at ~40 km, instead of 100 km. Consequently, the performances of 20–100-km PONs are experimentally investigated, and at least 33-Gbps capacity is achieved to support LR-PONs of all possible 20–100-km radii.
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cost effective 33 gbps Intensity Modulation direct detection multi band ofdm lr pon system employing a 10 ghz based transceiver
Optics Express, 2011Co-Authors: Dar Zu Hsu, Hsingyu Chen, Chiachien Wei, Jyehong ChenAbstract:We develop a dynamic multi-band OFDM subcarrier allocation scheme to fully utilize the available bandwidth under the restriction of dispersion- and chirp-related power fading. The experimental results successfully demonstrate an Intensity-Modulation-direct-detection 34.78-Gbps OFDM signal transmissions over 100-km long-reach (LR) passive-optical networks (PONs) based on a cost-effective 10-GHz EAM and a 10-GHz PIN. Considering 0–100-km transmission bandwidth of a 10-GHz EAM, the narrowest bandwidth is theoretically evaluated to occur at ~40 km, instead of 100 km. Consequently, the performances of 20–100-km PONs are experimentally investigated, and at least 33-Gbps capacity is achieved to support LR-PONs of all possible 20–100-km radii.
Jianping Yao - One of the best experts on this subject based on the ideXlab platform.
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a narrow passband and frequency tunable microwave photonic filter based on phase Modulation to Intensity Modulation conversion using a phase shifted fiber bragg grating
IEEE Transactions on Microwave Theory and Techniques, 2012Co-Authors: Wangzhe Li, Ming Li, Jianping YaoAbstract:A novel approach to implementing a narrow-passband and frequency-tunable microwave photonic filter (MPF) based on phase-Modulation to Intensity-Modulation conversion in a phase-shifted fiber Bragg grating (PS-FBG) is proposed and experimentally demonstrated. In the proposed MPF, a phase-modulated signal is sent to a PS-FBG. If one of the sidebands falls in the notch of the PS-FBG, the phase-modulated signal is converted to an Intensity-modulated signal. Due to the ultra-narrow notch of the PS-FBG, a microwave filter with an ultra-narrow passband is realized. The tunability of the microwave filter is achieved by tuning the wavelength of the optical carrier. A theoretical analysis is performed in which the value of the phase shift and the location of the phase shift in the PS-FBG on the frequency response of the MPF are studied. Two PS-FBGs with different reflection bandwidths and different phase-shift values introduced at the center of the gratings are fabricated and incorporated into the proposed MPF. For the two PS-FBGs, the 3-dB bandwidths are 120 and 60 MHz and the tunable ranges are 5.5 and 15 GHz.
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a wideband frequency tunable optoelectronic oscillator incorporating a tunable microwave photonic filter based on phase Modulation to Intensity Modulation conversion using a phase shifted fiber bragg grating
IEEE Transactions on Microwave Theory and Techniques, 2012Co-Authors: Jianping YaoAbstract:An optically tunable optoelectronic oscillator (OEO) with a wide frequency tunable range incorporating a tunable microwave photonic filter implemented based on phase-Modulation to Intensity-Modulation conversion using a phase-shifted fiber Bragg grating (PS-FBG) is proposed and experimentally demonstrated. The PS-FBG in conjunction with two optical phase modulators in the OEO loop form a high-Q, wideband and frequency-tunable microwave photonic bandpass filter, to achieve simultaneously single-frequency selection and frequency tuning. Since the tuning of the microwave filter is achieved by tuning the wavelength of the incident light wave, the tunability can be easily realized at a high speed. A theoretical analysis is performed, which is verified by an experiment. A microwave signal with a frequency tunable from 3 GHz to 28 GHz is generated. To the best of our knowledge, this is the widest frequency tunable range ever achieved by an OEO. The phase noise performance of the OEO is also investigated.
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instantaneous microwave frequency measurement with improved measurement range and resolution based on simultaneous phase Modulation and Intensity Modulation
Journal of Lightwave Technology, 2009Co-Authors: Xihua Zou, Jianping YaoAbstract:A novel approach to implementing instantaneous microwave frequency measurement based on simultaneous optical phase Modulation and Intensity Modulation with improved measurement range and resolution is proposed and experimentally demonstrated. The simultaneous optical phase Modulation and Intensity Modulation are implemented using a polarization modulator (PolM) in conjunction with an optical polarizer. The phase- and Intensity-modulated optical signals are then sent to a dispersive element, to introduce chromatic dispersions, which results in two complementary dispersion-induced power penalty functions. The ratio between the two power penalty functions has a unique relationship with the microwave frequency. Therefore, by measuring the microwave powers and calculating the power ratio, the microwave frequency can be estimated. Thanks to the complementary nature of the power penalty functions, a power ratio having a faster change rate versus the input frequency, i.e., a greater first-order derivative, is resulted, which ensures an improved measurement range and resolution. The proposed approach for microwave frequency measurement of a continuous-wave and a pulsed microwave signal is experimentally investigated. A frequency measurement range as large as 17 GHz with a measurement resolution of plusmn 0.2 GHz for a continuous-wave microwave signal and plusmn0.5 GHz for a pulsed microwave signal is achieved.
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Analytical Models for Phase-Modulation-Based Microwave Photonic Systems With Phase Modulation to Intensity Modulation Conversion Using a Dispersive Device
Journal of Lightwave Technology, 2009Co-Authors: Hao Chi, Xihua Zou, Jianping YaoAbstract:Recently, optical phase Modulation has been widely used in microwave photonics (MWP) systems, such as radio over fiber systems, photonic microwave filters, optical microwave and millimeter-wave signal generators, and optical subcarrier frequency up-converters. An optical phase-modulated signal can be converted to an Intensity-modulated signal in a dispersive optical fiber. Due to the intrinsic nonlinearity of optical phase Modulation, for linear applications such as microwave signal distribution and filtering, the Modulation index should be kept small to minimize the unwanted Modulation nonlinearity. However, for nonlinear applications such as microwave frequency multiplication and subcarrier frequency upconversion, the Modulation index should be large to maximize the frequency multiplication and upconversion efficiency. In this paper, for the first time to our knowledge, we develop a thorough theoretical framework for the characterization of phase-Modulation-based MWP systems, in which the phase Modulation to Intensity Modulation conversion is realized using a dispersive fiber. Analytical models for the distributions of single-tone and two-tone microwave signals and for microwave frequency multiplication and subcarrier frequency upconversion are developed, which are verified by numerical simulations. The analytical models for single-tone and two-tone transmissions are further confirmed by experiments. The developed analytical models provide an accurate mathematical tool in designing phase-Modulation-based MWP systems.
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Frequency domain analysis of fiber bragg grating based phase Modulation to Intensity Modulation conversion
Photonic Applications in Nonlinear Optics Nanophotonics and Microwave Photonics, 2005Co-Authors: Fei Zeng, Jianping YaoAbstract:In this paper, optical phase Modulation to Intensity Modulation by the use of a fiber Bragg grating (FBG) based frequency discriminator is proposed and experimentally demonstrated. In the proposed approach, the optical carrier frequency is placed at the quadrature point of the positive or negative slope of the reflection response of the FBG. The phase modulated light reflected from the two opposite slopes will have a π phase difference, which makes bipolar operation possible in an all-optical microwave signal processor or an optical code division multiple-access system. Both the frequency and phase responses of the FBG are taken into account to build a theoretical model in a frequency domain. Phase Modulation to Intensity Modulation conversion based on a Gaussian apodized FBG is experimentally implemented. The results confirm the theoretical analysis.
Hsingyu Chen - One of the best experts on this subject based on the ideXlab platform.
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optical filter requirements in an eml based single sideband pam4 Intensity Modulation and direct detection transmission system
Optics Express, 2017Co-Authors: Hsingyu Chen, Noriaki Kaneda, Jyehong Chen, Youngkai ChenAbstract:The feasibility of a single sideband (SSB) PAM4 Intensity-Modulation and direct-detection (IM/DD) transmission based on a CMOS ADC and DAC is experimentally demonstrated in this work. To cost effectively build a >50 Gb/s system as well as to extend the transmission distance, a low cost EML and a passive optical filter are utilized to generate the SSB signal. However, the EML-induced chirp and dispersion-induced power fading limit the requirements of the SSB filter. To separate the effect of signal-signal beating interference, filters with different roll-off factors are employed to demonstrate the performance tolerance at different transmission distance. Moreover, a high resolution spectrum analysis is proposed to depict the system limitation. Experimental results show that a minimum roll-off factor of 7 dB/10GHz is required to achieve a 51.84Gb/s 40-km transmission with only linear feed-forward equalization.
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cost effective 33 gbps Intensity Modulation direct detection multi band ofdm lr pon system employing a 10 ghz based transceiver
Optics Express, 2011Co-Authors: Hsingyu Chen, Wei Yuan Li, Jyehong ChenAbstract:We develop a dynamic multi-band OFDM subcarrier allocation scheme to fully utilize the available bandwidth under the restriction of dispersion- and chirp-related power fading. The experimental results successfully demonstrate an Intensity-Modulation-direct-detection 34.78-Gbps OFDM signal transmissions over 100-km long-reach (LR) passive-optical networks (PONs) based on a cost-effective 10-GHz EAM and a 10-GHz PIN. Considering 0–100-km transmission bandwidth of a 10-GHz EAM, the narrowest bandwidth is theoretically evaluated to occur at ~40 km, instead of 100 km. Consequently, the performances of 20–100-km PONs are experimentally investigated, and at least 33-Gbps capacity is achieved to support LR-PONs of all possible 20–100-km radii.
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cost effective 33 gbps Intensity Modulation direct detection multi band ofdm lr pon system employing a 10 ghz based transceiver
Optics Express, 2011Co-Authors: Dar Zu Hsu, Hsingyu Chen, Chiachien Wei, Jyehong ChenAbstract:We develop a dynamic multi-band OFDM subcarrier allocation scheme to fully utilize the available bandwidth under the restriction of dispersion- and chirp-related power fading. The experimental results successfully demonstrate an Intensity-Modulation-direct-detection 34.78-Gbps OFDM signal transmissions over 100-km long-reach (LR) passive-optical networks (PONs) based on a cost-effective 10-GHz EAM and a 10-GHz PIN. Considering 0–100-km transmission bandwidth of a 10-GHz EAM, the narrowest bandwidth is theoretically evaluated to occur at ~40 km, instead of 100 km. Consequently, the performances of 20–100-km PONs are experimentally investigated, and at least 33-Gbps capacity is achieved to support LR-PONs of all possible 20–100-km radii.
Wangzhe Li - One of the best experts on this subject based on the ideXlab platform.
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spurious noises analysis of microwave photonic filters based on phase Modulation to Intensity Modulation conversion using an optical notch filter
Journal of Lightwave Technology, 2014Co-Authors: Peixuan Li, Wangzhe LiAbstract:The spurious noises of a narrow-bandpass microwave photonic filter (MPF) using phase Modulation to Intensity Modulation (PM-IM) conversion and an optical notch filter are analyzed in theory and demonstrated experimentally. Due to the difference between the nonlinear filtering effect of PM-IM conversion and the linear one of finite impulse response or infinite impulse response, additional spurious noises will be generated in the former filter. Analysis models with two input microwave tones are developed for revealing the spurious noises in the MPF based on PM-IM conversion under small-signal and large-signal Modulations, which are then verified by simulations and experiments, respectively. The results show that, besides the target microwave signal to be selected, the inter-Modulation noise and the harmonic noises also coexist at the output of the MPF, wherein the 2nd-order inter-Modulation noises and the 2nd-order harmonic noise of the target signal are the dominant spurious ones. Therefore, an excellent agreement among the results from analysis models, the simulations, and the experiments is obtained.
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a narrow passband and frequency tunable microwave photonic filter based on phase Modulation to Intensity Modulation conversion using a phase shifted fiber bragg grating
IEEE Transactions on Microwave Theory and Techniques, 2012Co-Authors: Wangzhe Li, Ming Li, Jianping YaoAbstract:A novel approach to implementing a narrow-passband and frequency-tunable microwave photonic filter (MPF) based on phase-Modulation to Intensity-Modulation conversion in a phase-shifted fiber Bragg grating (PS-FBG) is proposed and experimentally demonstrated. In the proposed MPF, a phase-modulated signal is sent to a PS-FBG. If one of the sidebands falls in the notch of the PS-FBG, the phase-modulated signal is converted to an Intensity-modulated signal. Due to the ultra-narrow notch of the PS-FBG, a microwave filter with an ultra-narrow passband is realized. The tunability of the microwave filter is achieved by tuning the wavelength of the optical carrier. A theoretical analysis is performed in which the value of the phase shift and the location of the phase shift in the PS-FBG on the frequency response of the MPF are studied. Two PS-FBGs with different reflection bandwidths and different phase-shift values introduced at the center of the gratings are fabricated and incorporated into the proposed MPF. For the two PS-FBGs, the 3-dB bandwidths are 120 and 60 MHz and the tunable ranges are 5.5 and 15 GHz.
Kazuo Hotate - One of the best experts on this subject based on the ideXlab platform.
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spatial resolution improvement based on Intensity Modulation in measurement of brillouin dynamic grating localized by correlation domain technique
OFS2012 22nd International Conference on Optical Fiber Sensors, 2012Co-Authors: Rodrigo Kendy Yamashita, Kazuo HotateAbstract:We demonstrated that Intensity Modulation synchronized with laser frequency Modulation enhances the spatial resolution in the measurement of Brillouin dynamic grating (BDG) spectrum localized by the correlation domain technique. Following the correlation domain principle, the stimulated Brillouin scattering is localized in so-called correlation peak, but the peak actually has side lobes which excite the BDG out of the peak region. To overcome this, we applied Intensity Modulation and apodize the optical spectrum of the participating waves to suppress the side lobes. We confirmed spatial resolution improvement from 75 cm to 17 cm in a measurement fiber of 500 m.
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simulation and experiment for verifying Intensity Modulation scheme in brillouin optical correlation domain reflectometry
Conference on Lasers and Electro-Optics, 2012Co-Authors: Sitthipong Manotham, Masato Kishi, Kazuo HotateAbstract:Intensity Modulation scheme in Brillouin optical correlation domain reflectometry is verified both by simulation and experiment. The simulation results are in good agreement with the experiments. The optimized waveform for the Modulation is clarified to be effective.
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1 cm spatial resolution with large dynamic range in strain distributed sensing by brillouin optical correlation domain reflectometry based on Intensity Modulation
Third Asia Pacific Optical Sensors Conference, 2012Co-Authors: Sitthipong Manotham, Masato Kishi, Kazuo HotateAbstract:We experimentally demonstrate distributed strain measurement with a high spatial resolution and a large dynamic range by proposing a system for Brillouin optical correlation domain reflectometry with an Intensity Modulation scheme. With the optimized Intensity Modulation, the optical power spectrum of the light source is properly modified so that the accumulated background noise in the Brillouin gain spectrum is significantly reduced. It is confirmed that the proposed system enables us to extend the maximum measurable strain up to ~7000 μe, which is sufficient for practical applications of a distributed sensing, with 1-cm spatial resolution. This resolution is the best result ever reported in reflectometries based on spontaneous Brillouing scattering by using a conventional single mode fiber.
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Dynamic range enhancement in reflectometry by synthesis of optical coherence function with half-wave Intensity Modulation
2011 Optical Fiber Communication Conference and Exposition and the National Fiber Optic Engineers Conference, 2011Co-Authors: Koji Kajiwara, Zuyuan He, Kazuo HotateAbstract:Half-wave Intensity Modulation is proposed for apodization in synthesis of optical coherence function to suppress side-lobes around synthesized delta-function-like coherence peak, which realizes higher dynamic range of reflectometry applications.
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Background noise suppression in Brillouin Optical Correlation Domain Reflectometry based on optimized Intensity Modulation
17th Microopics Conference (MOC), 2011Co-Authors: Sitthipong Manotham, Masato Kishi, Kazuo HotateAbstract:The optimized Intensity Modulation is applied to Brillouin Optical Correlation Domain Reflectometry in order to modify optical power spectrum of the light source for suppressing the noise floor in Brillouin Gain Spectrum. The noise level suppression is experimentally demonstrated, and the performance of distributed strain measurement is much improved.