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Modified frequency-shifted interferometer:encoding wavelength into phase 被引量:1
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作者 Xi Chen Ciming Zhou +6 位作者 Dian Fan Li Qian Yandong Pang Cong Wei Chenguang Zhao Sijing Liang Yuxiao Li 《Chinese Optics Letters》 SCIE EI CAS CSCD 2020年第10期29-32,共4页
We propose a novel modified frequency-shifted interferometer, where a Mach–Zehnder interferometer is added in order to obtain wavelength information. We use the Hilbert transform to extract the wavelength information... We propose a novel modified frequency-shifted interferometer, where a Mach–Zehnder interferometer is added in order to obtain wavelength information. We use the Hilbert transform to extract the wavelength information from the phase of the interference pattern and construct the relationship between phase and wavelength. The laser wavelength measurement experiment is used to verify the compound interferometer. Experimental results demonstrated that our method could obtain the wavelength from the phase, which is of great significance for demodulation of the fiber Bragg grating based on a frequency-shifted interferometer. 展开更多
关键词 modified frequency-shifted interferometry phase difference Hilbert transform
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All-in-fiber amplification and compression of coherent frequency-shifted solitons tunable in the 1800–2000 nm range 被引量:1
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作者 GRZEGORZ SOBON TADEUSZ MARTYNKIEN +3 位作者 DOROTA TOMASZEWSKA KAROL TARNOWSKI PAWEL MERGO JAROSEAW SOTOR 《Photonics Research》 SCIE EI 2018年第5期368-372,共5页
We report an all-fiber, all-polarization maintaining(PM) source of widely tunable(1800–2000 nm) ultrashort pulses based on the amplification of coherent self-frequency-shifted solitons generated in a highly nonlinear... We report an all-fiber, all-polarization maintaining(PM) source of widely tunable(1800–2000 nm) ultrashort pulses based on the amplification of coherent self-frequency-shifted solitons generated in a highly nonlinear fiber pumped with an Er-doped fiber laser. The system delivers sub-100 fs pulses with energies up to 8.6 nJ and is built entirely from PM optical fibers, without any free-space optics. The all-fiber alignment-free design significantly increases the suitability of such a source for field deployments. 展开更多
关键词 nm range All-in-fiber amplification and compression of coherent frequency-shifted solitons tunable in the 1800 PM
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Generation of sub-100 fs pulses tunable from 1700 to 2100 nm from a compact frequency-shifted Er-fiber laser 被引量:4
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作者 GRZEGORZ SOBON TADEUSZ MARTYNKIEN +2 位作者 KAROL TARNOWSKI PAWEL MERGO JAROSLAW SOTOR 《Photonics Research》 2017年第3期151-155,共5页
We report generation of sub-100 fs pulses tunable from 1700 to 2100 nm via Raman soliton self-frequency shift.The nonlinear shift occurs in a highly nonlinear fiber, which is pumped by an Er-doped fiber laser. The who... We report generation of sub-100 fs pulses tunable from 1700 to 2100 nm via Raman soliton self-frequency shift.The nonlinear shift occurs in a highly nonlinear fiber, which is pumped by an Er-doped fiber laser. The whole system is fully fiberized, without the use of any free-space optics. Thanks to its exceptional simplicity, the setup can be considered as an alternative to mode-locked Tm-and Ho-doped fiber lasers. 展开更多
关键词 of as be Generation of sub-100 fs pulses tunable from 1700 to 2100 nm from a compact frequency-shifted Er-fiber laser in NM from
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Anti-interference performance analysis of frequency-shift filter in scenario of multiple WPANs accessing HAN
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作者 胡亚锟 沈连丰 +2 位作者 宋铁成 夏玮玮 胡静 《Journal of Southeast University(English Edition)》 EI CAS 2008年第2期133-138,共6页
In the scenario of multiple wireless personal area networks (WPANs) accessing the home area network (HAN), the frequency-shift (FRESH)filter based on the cyclostationary theory is applied for the anti-interferen... In the scenario of multiple wireless personal area networks (WPANs) accessing the home area network (HAN), the frequency-shift (FRESH)filter based on the cyclostationary theory is applied for the anti-interference at the 2. 4 GHz spectrum. The main architecture of multiple WPANs accessing the HAN is proposed. The medium access control( MAC) -level coordination solution applied in the access point (AP)for the coexistence of different communication protocols within WPAN is discussed. The diagram of the adaptive FRESH filter is described. The anti-interference models of the FRESH filter in the scenario of multiple WPANs accessing the HAN are proposed. The minimum mean square error (MMSE)convergence property of the FRESH filter with the change in the data point number is analyzed. The simulation results indicate that the FRESH filter can effectively extract the signal of interest (SOI) from the interference with the partly overlapped spectrum. Thus, the excellent anti-interference performance of the FRESH filter is validated. Moreover, by both theoretical analysis and simulation, the MMSE convergent property of the FRESH filter is also proven. 展开更多
关键词 CYCLOSTATIONARY frequency-shift filter antiinterference wireless personal area networks home area network minimum mean square error
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Landau damping and frequency-shift of a quadrupole mode in a disc-shaped rubidium Bose–Einstein condensate 被引量:4
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作者 阿孜古丽.热合木提 彭胜强 马晓栋 《Chinese Physics B》 SCIE EI CAS CSCD 2014年第9期118-124,共7页
The damping and frequency-shift in Landau mechanism of a quadrupole mode in a disc-shaped rubidium Bose-Einstein condensate are investigated by using the Hartree-Fock-Bogoliubov approximation. The practical relaxation... The damping and frequency-shift in Landau mechanism of a quadrupole mode in a disc-shaped rubidium Bose-Einstein condensate are investigated by using the Hartree-Fock-Bogoliubov approximation. The practical relaxations of the elementary excitations and the orthometric relation among them are taken into account to obtain advisable calculation formula for damping as well as frequency-shift. The first approximation of Gaussian distribution function is employed for the ground-state wavefunction to suitably eliminate the divergence of the analytic three-mode coupling matrix elements. According to these methods, both Landau damping rate and frequency-shift of the quadrupole mode are analytically calculated. In addition, all the theoretical results agree with the experimental ones. 展开更多
关键词 Bose-Einstein condensate Landau damping and frequency-shift Hartree-Fock-Bogoliubov approximation Thomas-Fermi approximation
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A wideband frequency-shift keying demodulator for wireless neural stimulation microsystems
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作者 DONG Mian ZHANG Chun +2 位作者 MAI Song-ping WANG Zhi-hua LI Dong-mei 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2006年第6期1056-1060,共5页
This paper presents a wideband frequency-shift keying (FSK) demodulator suitable for a digital data transmission chain of wireless neural stimulation microsystems such as cochlear implants and retinal prostheses. Th... This paper presents a wideband frequency-shift keying (FSK) demodulator suitable for a digital data transmission chain of wireless neural stimulation microsystems such as cochlear implants and retinal prostheses. The demodulator circuit derives a constant frequency clock directly from an FSK carrier, and uses this clock to sample the data bits. The circuit occupies 0.03 mm^2 using a 0.6 μm, 2M/2P, standard CMOS process, and consumes 0.25 mW at 5 V. This circuit was experimentally tested at transmission speed of up to 2.5 Mbps while receiving a 5-10 MHz FSK carrier signal in a cochlear implant system. 展开更多
关键词 Biomedical implants CMOS DEMODULATOR frequency-shift keying (FSK) Cochlear implant
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Gravitational frequency-shift and deflection of light by quintessence
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作者 陈菊华 王永久 《Chinese Physics B》 SCIE EI CAS CSCD 2007年第11期3212-3215,共4页
In this paper we investigate the gravitational frequency-shift and deflection of light in the Schwarzschild black hole space-time surrounded by quintessence. With the analytical and numerical methods, we find that the... In this paper we investigate the gravitational frequency-shift and deflection of light in the Schwarzschild black hole space-time surrounded by quintessence. With the analytical and numerical methods, we find that the gravitational frequency-shift of light in the Schwarzschild black hole space-time surrounded by the quintessence increases as the values of the normalization factor c increases, but the gravitational frequency-shift of light decreases with the quintessential state parameter Wq increasing. We also calculate the deflection of light by quintessence and find that the deflection rate decreases as the values of the quintessential parameters c and Wq increase. 展开更多
关键词 frequency-shift DEFLECTION QUINTESSENCE
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BLIND CHANNEL ESTIMATION OF SPACE-TIME FREQUENCY-SHIFT KEYING
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作者 Gao Yuanyuan Yi Xiaoxin Qian Zuping Hu Xianbing 《Journal of Electronics(China)》 2006年第2期277-281,共5页
The decoupled coherent Maximum Likelihood (ML) detection algorithm presented in this letter can sharply reduce the complexity of the receiver as well as provide better error performance under the precondition that cha... The decoupled coherent Maximum Likelihood (ML) detection algorithm presented in this letter can sharply reduce the complexity of the receiver as well as provide better error performance under the precondition that channel should be estimated first. Considering the bandwidth inefficiency of Frequency Shift Keying (FSK), the acquisition of channel state information through training sequences will further decrease the transmission efficiency. This letter presents a blind channel estimation algorithm based on noise subspace theory which can acquire channel information without any training symbols. The simulation shows that the algorithm brings about fewer channel estimation errors while the frequency efficiency can be increased. 展开更多
关键词 Space-Time frequency-shift Keying (ST-FSK) Maximum Likelihood (ML) Subspace algorithm Blind channel estimation
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Landau Damping of Collective Modes in a Disc-Shaped Bose-Einstein Condensate 被引量:5
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作者 马晓栋 马永利 黄国翔 《Chinese Physics Letters》 SCIE CAS CSCD 2007年第3期616-619,共4页
We investigate the Landau damping of collective modes in an anisotropic Bose Einstein condensate (BEC), Based on divergence-free analytical solutions for the ground state wavefunction of the condensate and all eigen... We investigate the Landau damping of collective modes in an anisotropic Bose Einstein condensate (BEC), Based on divergence-free analytical solutions for the ground state wavefunction of the condensate and all eigenvalues and eigenfunctions for thermal excited quasiparticles, we make a detailed analytical calculation on coupling matrix elements. We evaluate the Landau damping of a quadrupole collective mode in the BEC with a disc-shaped trap and discuss its dependence on temperature and particle number of the system. 展开更多
关键词 frequency-shiftS EXCITATIONS
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Parameter Estimation Approach of FSK/PSK Radar Signal
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作者 Hui Xiong De-Guo Zeng Xiao-Dong He Bin Tang 《Journal of Electronic Science and Technology》 CAS 2010年第4期341-345,共5页
A parameter estimation approach of reconnaissance hybrid radar signal combined frequency-shift keying (FSK) and phase-shift keying (PSK) is presented. Firstly, the multi-phase difference is adopted to calculate th... A parameter estimation approach of reconnaissance hybrid radar signal combined frequency-shift keying (FSK) and phase-shift keying (PSK) is presented. Firstly, the multi-phase difference is adopted to calculate the instantaneous frequency (IF) of FSK/PSK, then the frequency points of FSK are estimated from the histogram of IF. The code rate of PSK is extracted from the locations of phase discontinuity. Finally, the multi-phase difference of the square of the received signal is computed to estimate the code rate of FSK. The presented algorithm has higher accuracy of parameter estimation when the signal-to-noise ratio (SNR) is above 11 dB. 展开更多
关键词 Fast Fourier transform (FFT) frequency-shift keying/phase-shift keying (FSK/PSIC) parameter estimation phase difference computation.
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SOME BLIND FRESH EQUALIZATION ALGORITHMS WITH ANTI-INTERFERENCE CAPABILITIES
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作者 Zhou Ke Cao Shike Song Rongfang Zhang Lijun 《Journal of Electronics(China)》 2008年第6期768-773,共6页
Some novel blind FREquency-SHift (FRESH) equalizer algorithms are proposed for the equalization of Finite Impulse Response (FIR) single channel with anti-interference capabilities. These algorithms based on FRESH filt... Some novel blind FREquency-SHift (FRESH) equalizer algorithms are proposed for the equalization of Finite Impulse Response (FIR) single channel with anti-interference capabilities. These algorithms based on FRESH filter can work well without any training sequence. Simulation results show that the equalizer algorithms can effectively reject many types of interferences and the performances of these new equalizer algorithms are superior to the conventional equalizer algorithms. 展开更多
关键词 Blind equalization CYCLOSTATIONARITY frequency-shift (FRESH) filter
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The application of sample-and-hold circuits in the laser frequency-shifting
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作者 周蜀渝 周善钰 王育竹 《Chinese Optics Letters》 SCIE EI CAS CSCD 2005年第9期524-526,共3页
A new method of frequency-shifting for a diode laser is realized. Using a sample-and-hold circuit, the error signal can be held by the circuit during frequency shifting. It can avoid the restraint of locking or even l... A new method of frequency-shifting for a diode laser is realized. Using a sample-and-hold circuit, the error signal can be held by the circuit during frequency shifting. It can avoid the restraint of locking or even lock-losing caused by the servo circuit when we input a step-up voltage into piezoelectric transition (PZT) to achieve laser frequency-shifting. 展开更多
关键词 The application of sample-and-hold circuits in the laser frequency-shifting AOM
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Generation of dual and quad‑optical frequency combs in the injected radiation free mode‑locked frequency‑shifted feedback laser
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作者 Sergey N.Mantsevich Ekaterina I.Kostyleva +1 位作者 Andrey N.Danilin Vladimir S.Khorkin 《Frontiers of Optoelectronics》 EI CSCD 2023年第3期43-56,共14页
The results of an optoelectronic system—frequency-shifted feedback(FSF)laser experimental examination are presented.The considered FSF laser is seeded only with optical amplifer spontaneous emission(ASE)and operates ... The results of an optoelectronic system—frequency-shifted feedback(FSF)laser experimental examination are presented.The considered FSF laser is seeded only with optical amplifer spontaneous emission(ASE)and operates in the mode-locked regime,whereby the output radiation is sequence of short pulses with a repetition rate determined by the delay time in its optical feedback circuit.In the frequency domain,the spectrum of such a pulse sequence is an optical frequency comb(OFC).These OFCs we call initial.We consider the possibility of tunable acousto-optic(AO)dual and quad-comb frequency spacing downconversion in the FSF laser seeded with ASE and operating in the mode-locked regime.The examined system applies a single frequency shifting loop with single AO tunable flter as the frequency shifter that is fed with several radio frequency signals simultaneously.The initial OFCs with frequency spacing of about 6.5 MHz may be obtained in the wide spectral range and their width,envelope shape and position in the optical spectrum may be tuned.The dual-combs are obtained with a pair of initial OFCs aroused by two various ultrasound waves in the acousto-optic tunable flter(AOTF).The dual-combs frequency spacing is determined by the frequency diference of the signals applied to the AOTF piezoelectric transducer and can be tuned simply.The quad-combs are obtained with three initial OFCs,forming a pair of dual-combs,appearing when three ultrasound frequencies feed the AOTF transducer.The quad-combs frequency spacing is defned by the diference between the frequency spacing of dual-combs.Quad-combs with more than 5000 spectral lines and tunable frequency spacing are observed.The successive frequency downconversion gives the possibility to reduce the OFC frequency spacing form several MHz for initial OFC to tens of kHz for quad-combs. 展开更多
关键词 frequency-shifted feedback laser Optical frequency combs ACOUSTO-OPTICS Dual-combs Quad-combs
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