The Experts below are selected from a list of 106464 Experts worldwide ranked by ideXlab platform
Jianping Yao - One of the best experts on this subject based on the ideXlab platform.
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on chip two step Microwave Frequency measurement with high accuracy and ultra wide bandwidth using add drop micro disk resonators
Optics Letters, 2019Co-Authors: Yang Chen, Weifeng Zhang, Jingxuan Liu, Jianping YaoAbstract:An on-chip two-step Microwave Frequency measurement method with high accuracy and an ultra-wide Frequency measurement range is reported. A silicon photonic integrated micro-disk resonator (MDR) array is used to coarsely measure the signal Frequency via an array of add-drop MDRs with smaller disk radii; then an MDR with a larger radius is used to finely measure the signal Frequency, which is done by monitoring the optical powers of the optical signals from the through port and drop port of the MDRs. The proposed system features a very compact structure, ultra-wide Frequency measurement range, and high Frequency measurement accuracy, which is verified by a proof-of-concept experiment using two MDRs with radii of 6 and 10 μm. A Frequency measurement of Microwave signals from 1.6 to 40 GHz is implemented with a measurement error of less than 60 MHz. The stability of the system is also evaluated.
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ultrahigh resolution photonic assisted Microwave Frequency identification based on temporal channelization
IEEE Transactions on Microwave Theory and Techniques, 2013Co-Authors: Chao Wang, Jianping YaoAbstract:Real-time ultrahigh-resolution Microwave Frequency identification is paramount for widespread applications, such as communications, radar, and electronic warfare. Photonics-assisted Microwave Frequency identification can be achieved using an optical channelizer. While this technique enables simultaneous measurement of multiple frequencies, it has poor measurement resolution due to the large channel spacing, which is usually greater than 1 GHz. Here, we introduce a new channelizer-based Microwave Frequency measurement technique that offers nearly 500 times higher spectral resolution. This method employs largely dispersed broadband optical pulses to encode the time-domain characteristics of the modulating signal to the optical spectral domain. An optical channelizer is employed to slice the spectrum, which is equivalent to performing temporal sampling of the time-domain waveform. The unknown Microwave signal is then reconstructed and its spectral distribution is analyzed by a digital processor. To evaluate the proposed technique, Frequency measurements of a single-tone, a multiple-tone, and a Frequency-hopping Microwave signal are demonstrated. A measurement resolution as high as 55 MHz is achieved using an optical channelizer with a channel spacing of 25 GHz.
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investigation of photonically assisted Microwave Frequency multiplication based on external modulation
IEEE Transactions on Microwave Theory and Techniques, 2010Co-Authors: Jianping YaoAbstract:Microwave Frequency multiplication based on external modulation using two cascaded Mach-Zehnder modulators (MZMs) has been considered an effective solution for high-Frequency and Frequency-tunable Microwave signal generation. Different techniques have been demonstrated recently, but no generalized approach has been developed. In this paper, a generalized approach to achieving Microwave Frequency multiplication using two cascaded MZMs is presented. A theoretical analysis leading to the operating conditions to achieve Frequency quadrupling, sextupling, or octupling is developed. The system performance in terms of phase noise, tunability, and stability is also investigated.
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instantaneous Microwave Frequency measurement using a photonic Microwave filter pair
IEEE Photonics Technology Letters, 2010Co-Authors: Shilong Pan, Jianping YaoAbstract:Photonics-assisted instantaneous Microwave Frequency measurement (IFM) has been a topic of interest recently. To perform IFM, an amplitude comparison function (ACF) that relates the Microwave Frequency to the Microwave powers by which the Microwave Frequency can be estimated by measuring the Microwave powers should be established. In this letter, a two-tap photonic Microwave filter pair with complementary Frequency responses is employed for achieving IFM. Thanks to the complementary nature of the transfer functions of the filter pair, a quasi-linear monotonically decreasing ACF over a large Frequency band is obtained, which ensures an improved measurement range and accuracy. An experiment is performed. A Microwave Frequency measurement range as large as 36 GHz with a measurement accuracy better than ±0.2 GHz is experimentally demonstrated.
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continuously tunable photonic Microwave Frequency multiplication by use of an unbalanced temporal pulse shaping system
IEEE Photonics Technology Letters, 2010Co-Authors: Chao Wang, Jianping YaoAbstract:A novel approach to achieving Microwave Frequency multiplication with a continuously tunable multiplication factor using an unbalanced temporal pulse shaping (TPS) system is proposed and demonstrated. The proposed TPS system consists of a Mach-Zehnder modulator and two dispersive elements having opposite dispersion values. Since the values of dispersion are not identical in magnitude, the entire system can be considered as a typical balanced TPS system for a real-time Fourier transformation followed by a residual dispersive element for a second real-time Fourier transformation. The Microwave Frequency multiplication factor is determined by the dispersion values of the two dispersive elements and can be continuously tunable by changing the values. Numerical simulations and experiments are performed. Microwave Frequency multiplication with a factor as high as 13.2 is experimentally demonstrated.
Xihua Zou - One of the best experts on this subject based on the ideXlab platform.
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photonic generation of Microwave Frequency shift keying signal using a polarization maintaining fbg
IEEE Photonics Journal, 2018Co-Authors: Lianshan Yan, Houjun Wang, Wei Pan, Bin Luo, Xihua ZouAbstract:A photonic generation of Microwave Frequency shift keying signal (FSK) with large Frequency tunability is proposed and experimentally demonstrated. A polarization modulator combined with a polarization maintaining fiber Bragg grating is used to transform a carrier-suppressed double sideband signal to a wavelength-shift-keying one, which is subsequently mixed with a tunable optical source to achieve Frequency modulation. A proof-of-concept experiment is demonstrated to obtain an FSK signal at 9.5/12.5 GHz. The carrier Frequency has been tuned from 7.2 to 14.8 GHz by adjusting the laser wavelength. Moreover, a radio over fiber transmission link is established to investigate the transmission performance of the generated FSK signal. The bit-error-rate curve of the received FSK signal at 9.5/12.5 GHz for a 5-km single mode fiber and 2-m wireless transmission is presented.
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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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Microwave Frequency measurement based on optical power monitoring using a complementary optical filter pair
IEEE Transactions on Microwave Theory and Techniques, 2009Co-Authors: Xihua Zou, Hao Chi, Jianping YaoAbstract:An approach to the measurement of a Microwave Frequency based on optical power monitoring using a complementary optical filter pair is proposed and investigated. In the proposed system, a Microwave signal is applied to a Mach-Zehnder modulator, which is biased at the minimum transmission point to suppress the optical carrier. The carrier-suppressed optical signal is then sent to the complementary optical filter pair, with the powers from the complementary filters measured by two optical power meters. A mathematical expression that relates the Microwave Frequency and the optical powers is developed. Experiments are performed to verify the effectiveness of the proposed approach. The performance of the proposed system in terms of the Frequency measurement range, operation stability, and robustness to noise is also investigated.
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an optical approach to Microwave Frequency measurement with adjustable measurement range and resolution
IEEE Photonics Technology Letters, 2008Co-Authors: Xihua Zou, Jianping YaoAbstract:We propose an approach for the measurement of Microwave Frequency in the optical domain with adjustable measurement range and resolution. In the proposed approach, two optical wavelengths with a large wavelength spacing are modulated by an unknown Microwave signal in a Mach-Zehnder modulator (MZM). The optical output from the MZM is sent to a dispersive fiber to introduce different chromatic dispersions, leading to different Microwave power penalties. The two wavelengths are then separated, with the Microwave powers measured by two photodetectors. A fixed relationship between the Microwave power ratio and the Microwave Frequency is established. The Microwave Frequency is estimated by measuring the two Microwave powers. The Frequency measurement range and resolution can be adjusted by tuning the wavelength spacing. Different Frequency measurement ranges and resolutions are demonstrated experimentally.
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an approach to the measurement of Microwave Frequency based on optical power monitoring
IEEE Photonics Technology Letters, 2008Co-Authors: Hao Chi, Xihua Zou, Jianping YaoAbstract:A novel approach to the measurement of Microwave Frequency based on optical power monitoring is proposed and demonstrated. The Microwave signal with its Frequency to be measured is modulated on two optical carriers with their wavelengths set at one peak and one valley of the spectral response of a sinusoidal filter. The modulation is performed by a Mach-Zehnder modulator that is biased to suppress the optical carriers. A mathematical expression relating the optical powers from the two wavelength channels and the Microwave Frequency to be measured is developed. By simply monitoring the optical powers at the outputs of the two wavelength channels, the Microwave Frequency can be evaluated. A proof-of-concept experiment is implemented. Frequency measurement with good accuracy for Microwave signals at different power levels is realized.
Hao Chi - One of the best experts on this subject based on the ideXlab platform.
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high resolution multiple Microwave Frequency measurement based on stimulated brillouin scattering
IEEE Photonics Technology Letters, 2012Co-Authors: Shilie Zheng, Xianmi Zhang, Hao ChiAbstract:A novel multiple Microwave Frequency measurement scheme is proposed based on the selective conversion of phase modulation to amplitude modulation, which is realized by stimulated Brillouin scattering. The principle of this scheme is theoretically elucidated with its advantages and disadvantages discussed. Experiments are established to verify its feasibility and the results show that this scheme is competent in determining the Frequency information among multiple Frequency signal with very high resolution and accuracy. The maximum measurement error is less than 30 MHz.
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photonic instantaneous Microwave Frequency measurement based on two different phase modulation to intensity modulation conversions
Optics Communications, 2011Co-Authors: Yun Wang, Hao Chi, Xianmin Zhang, Shilie Zheng, Xiaofeng JinAbstract:Abstract A novel photonic technique for instantaneous Frequency measurement of Microwave signal based on phase modulation to intensity modulation conversion is proposed and demonstrated. In the proposed system, an optical carrier is modulated by a Microwave signal with its Frequency to be measured through a phase modulator. The phase-modulated optical signal is then converted to intensity-modulated signals in two independent paths using a dispersive media and a Frequency discriminator respectively. Since the dependence of the received Microwave power on the input Microwave Frequency in the two paths differs, the Microwave power ratio between the two paths can be used to uniquely determine the Microwave Frequency. The major advantages of the approach lie in that only one laser source and the bias-free phase modulator is employed in the system, which improves the stability of the system. Experimental demonstrations of the Frequency measurement based on the proposed approach are presented.
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photonic instantaneous measurement of Microwave Frequency using fiber bragg grating
Optics Communications, 2010Co-Authors: Bo Yang, Hao Chi, Xianmin Zhang, Shilie Zheng, Xiaofeng JinAbstract:Abstract A photonic approach to realizing instantaneous measurement of Microwave Frequency based on optical monitoring using a fiber Bragg grating (FBG) is proposed and demonstrated. In the approach, a Frequency-unknown Microwave signal is modulated on an optical carrier in a Mach–Zehnder modulator biased at the minimum transmission point. After detecting the transmission and reflection optical powers at the output of the FBG, the Microwave Frequency can be determined according to the value of transmission-to-reflection power ratio, due to the fixed relationship between the Microwave Frequency and the power ratio. A proof-of-concept experiment has been performed, which demonstrates that a measurement resolution of ±0.08 GHz over a 10 GHz measurement bandwidth is achieved. The measurement performance in terms of resolution is better than previously reported results.
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instantaneous Microwave Frequency measurement using an optical phase modulator
IEEE Microwave and Wireless Components Letters, 2009Co-Authors: Xiaomi Zhang, Shilie Zheng, Hao Chi, Xianmi Zhang, Jianping YaoAbstract:A novel technique for instantaneous Microwave Frequency measurement using an optical phase modulator is proposed and demonstrated. In the proposed system, a Microwave signal with its Frequency to be measured is modulated on two optical wavelengths at the phase modulator, with the phase-modulated optical signals sent to a dispersive element, and detected at two photo-detectors. Due to the chromatic dispersion of the dispersive element, the two Microwave signals will experience different power fading, leading to different power versus Frequency functions. A fixed relationship between the Microwave Frequency and the Microwave powers is established. By measuring the Microwave powers, the Microwave Frequency is estimated. Compared with the techniques using an intensity modulator, the proposed approach is simpler with less loss. Since no bias is needed the system has a better stability, which is highly expected for defense applications. Experimental verification is presented.
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Microwave Frequency measurement based on optical power monitoring using a complementary optical filter pair
IEEE Transactions on Microwave Theory and Techniques, 2009Co-Authors: Xihua Zou, Hao Chi, Jianping YaoAbstract:An approach to the measurement of a Microwave Frequency based on optical power monitoring using a complementary optical filter pair is proposed and investigated. In the proposed system, a Microwave signal is applied to a Mach-Zehnder modulator, which is biased at the minimum transmission point to suppress the optical carrier. The carrier-suppressed optical signal is then sent to the complementary optical filter pair, with the powers from the complementary filters measured by two optical power meters. A mathematical expression that relates the Microwave Frequency and the optical powers is developed. Experiments are performed to verify the effectiveness of the proposed approach. The performance of the proposed system in terms of the Frequency measurement range, operation stability, and robustness to noise is also investigated.
Ninghua Zhu - One of the best experts on this subject based on the ideXlab platform.
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Simultaneous Microwave Frequency conversion and idler filtering based on polarization manipulating of an amplified spontaneous emission source
Optics and Laser Technology, 2020Co-Authors: Jun Wen, Difei Shi, Zhiyao Jia, Ninghua ZhuAbstract:Abstract We propose a technique to simultaneously realize Microwave Frequency conversion and idler filtering by polarization manipulating of an amplified spontaneous emission (ASE) source. By simply adjusting the tunable differential group delay (DGD) introduced by a polarization division multiplexed (PDM) emulator, switchable and idler-free Frequency conversion can be implemented. Thanks to the intrinsic Frequency selection of the dispersive delay structure, no electrical filter is involved to remove the mixing idlers, which ensures a broad operation bandwidth and flexible tunability. In addition, the dispersion-induced mixing power fading and the environmental vibration sensitivity that exist in previous approaches are both avoided owing to the PDM optical paths. The proposed method is theoretically and experimentally verified.
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multiple Frequency measurement based on a fourier domain mode locked optoelectronic oscillator operating around oscillation threshold
Optics Letters, 2019Co-Authors: Tengfei Hao, Jian Tang, Nuannuan Shi, Ninghua ZhuAbstract:We propose and experimentally demonstrate a photonic-assisted approach to Microwave Frequency measurement based on Frequency-to-time mapping using a Fourier domain mode-locked optoelectronic oscillator (FDML OEO) operating around oscillation threshold. A relationship between the Frequency of the unknown input Microwave signals and the time difference of the output pulses is established with the help of the Frequency scanning capability of the FDML OEO and, thus, can be used for Microwave Frequency measurement. The proposed scheme is characterized as having broad bandwidth, high resolution, multiple-Frequency detection capability, and tunable measurement range. Microwave Frequency measurement with a measurement range up to 16 GHz and a low measurement error of 0.07 GHz is realized.
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photonic assisted Microwave Frequency multiplier based on nonlinear polarization rotation
Optics Letters, 2014Co-Authors: Jianyu Zheng, Hui Wang, Lixian Wang, Jianguo Liu, Ninghua ZhuAbstract:A photonic-assisted Microwave Frequency multiplier (MFM) based on the Kerr shutter is proposed and demonstrated. In this MFM, the nonlinear polarization rotation in the high nonlinear optical fiber is used for the first time to implement the light-controlled optical-carrier-suppressed modulation. The Frequency-doubled Microwave signal with the Frequency up to 144 GHz is generated. The results of the experiment are in accordance with the theoretical prediction.
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brillouin assisted Microwave Frequency measurement with adjustable measurement range and resolution
Optics Letters, 2012Co-Authors: Ninghua Zhu, Lixia WangAbstract:We present a reconfigurable Microwave Frequency measurement technique with adjustable measurement range and resolution. The key novelty of the technique is the employment of stimulated Brillouin scattering, which results in a tunable amplitude comparison function, leading to an adjustable measurement range and resolution. The proposed technique is switchable between a wideband tunable narrow measurement range (∼2 GHz) with high resolution (±0.05 GHz) and a fixed wide measurement range (12 GHz) with moderate resolution (±0.25 GHz).
Jae Koo Lee - One of the best experts on this subject based on the ideXlab platform.
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abnormal electron heating mode and formation of secondary energetic electrons in pulsed Microwave Frequency atmospheric microplasmas
Physics of Plasmas, 2014Co-Authors: Hyunah Kwon, Soohyun Jung, H Y Kim, I H Won, Jae Koo LeeAbstract:The formation of secondary energetic electrons induced by an abnormal electron-heating mode in pulsed Microwave-Frequency atmospheric microplasmas was investigated using particle-in-cell simulation. We found that additional high electron heating only occurs during the first period of the ignition phase after the start of a second pulse at sub-millimeter dimensions. During this period, the electrons are unable to follow the abruptly retreating sheath through diffusion alone. Thus, a self-consistent electric field is induced to drive the electrons toward the electrode. These behaviors result in an abnormal electron-heating mode that produces high-energy electrons at the electrode with energies greater than 50 eV.
