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Wideband dipole logging based on segmen linear frequency modulation excitation 认领 引用 被引量：3
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作者 Cao Xue-Shen Chen Hao +3 位作者 Li Ping He Hong-Bin Zhou Yin-Qiu Wang XJu-Ming 《Applied Geophysics》 SCIE CSCD 2018年第2期197-207,362,共11页
A wideband dipole signal is required for dipole dispersion correction and nearborehole imaging. To obtain the broadband flexural wave dispersion, we use a nonlinear frequency modulation （NLFM） signal and propose a s... A wideband dipole signal is required for dipole dispersion correction and nearborehole imaging. To obtain the broadband flexural wave dispersion, we use a nonlinear frequency modulation （NLFM） signal and propose a segment linear frequency modulation （SLFM） signal as the dipole excitation signal to compensate for the excitation intensity. The signal-to-noise ratio （SNR） of the signal over the entire frequency band is increased. The finite-difference method is used to simulate the responses from a Ricker wavelet, a linear frequency modulation （LFM） signal, an NLFM signal, and an SLFM signal in two borehole models of a homogeneously hard formation and a radially stratified formation. The dispersion and radial tomography results at low SNR of the sound source signals are compared. Numerical modeling suggests that the energy of the flexural waves excited by the Ricker wavelet source is concentrated near the Airy phase. In this case, the dispersion is incomplete and information regarding the formation near or far from the borehole cannot be obtained. The LFM signal yields dispersion information near the Airy phase and the high-frequency range but not in the low-frequency range. Moreover, the information regarding the formation far from the borehole is not accurate. The NLFM signal extends the frequency range of the flexural waves by compensating for the excitation intensity and yields information regarding the formation information, but it is not easy to obtain. The SLFM signal yields the same results as the NLFM signal and is easier to implement. Consequently, the dipole detection range expands and the S-wave velocity calculation accuracy improves. 展开更多
关键词 Dipole acoustic logging dispersion frequency modulation finite difference
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A high frequency vibration compensation approach for ultrahigh resolution SAR imaging based on sinusoidal frequency modulation Fourier-Bessel transform 认领 引用 被引量：3
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作者 CHEN Siyu WANG Yong CAO Rui 《Journal of Systems Engineering and Electronics》 SCIE CSCD 2023年第4期894-905,共12页
Ultrahigh resolution synthetic aperture radar(SAR)imaging for ship targets is significant in SAR imaging,but it suffers from high frequency vibration of the platform,which will induce defocus into SAR imaging results.... Ultrahigh resolution synthetic aperture radar(SAR)imaging for ship targets is significant in SAR imaging,but it suffers from high frequency vibration of the platform,which will induce defocus into SAR imaging results.In this paper,a novel compensation method based on the sinusoidal frequency modulation Fourier-Bessel transform(SFMFBT)is proposed,it can estimate the vibration errors,and the phase shift ambiguity can be avoided via extracting the time frequency ridge consequently.By constructing the corresponding compensation function and combined with the inverse SAR(ISAR)technique,well-focused imaging results can be obtained.The simulation imaging results of ship targets demonstrate the validity of the proposed approach. 展开更多
关键词 synthetic aperture radar(SAR) high frequency vibration compensation sinusoidal frequency modulation FourierBessel transform(SFMFBT)
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Analysis of single frequency modulation for passive hydrogen maser 认领 引用 被引量：2
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作者 Hefei Zheng Jing Li +2 位作者 Wenming Wang Lianshan Gao Keming Feng 《Journal of Systems Engineering and Electronics》 SCIE CSCD 2017年第4期661-668,共8页
Based on the theory of the passive hydrogen maser, along with the technology of frequency modulation and modulation transfer spectroscopy, the theoretical expression of the single frequency modulation for the passive ... Based on the theory of the passive hydrogen maser, along with the technology of frequency modulation and modulation transfer spectroscopy, the theoretical expression of the single frequency modulation for the passive hydrogen maser and the function of the cavity and H line error signals separation are derived, which are basically coincident with the experiment. The absorption and dispersion spectrum curves with different resonance widths show that the cavity and hydrogen transition serve as discriminators, and the two error signals can be separated. Through the calculations of the two error signals in the passive hydrogen maser, it analyzes the traditional method of the two error signals separation, and then describes a new improved method for the passive hydrogen servo loops consisting in the use of a single modulation frequency and frequency discrimination. A null interaction of the two error signals for the new selection of the phase setting is deduced theoretically and validated by the simulation. The preliminary experimental result confirms the feasibility of this new approach, which can reduce the influence from the cavity frequency variety on the crystal oscillator and contribute significantly to the long term performance of the passive hydrogen maser. 展开更多
关键词 passive hydrogen maser single frequency modulation frequency discrimination
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Blind parameter estimation of pseudo-random binary code-linear frequency modulation signal based on Duffing oscillator at low SNR 认领 引用 被引量：1
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作者 Ke Wang Xiaopeng Yan† +2 位作者 Ze Li Xinhong Hao Honghai Yu 《Chinese Physics B》 SCIE EI CAS CSCD 2021年第5期312-319,共8页
Conventional parameter estimation methods for pseudo-random binary code-linear frequency modulation(PRBC-LFM)signals require prior knowledge,are computationally complex,and exhibit poor performance at low signal-to-no... Conventional parameter estimation methods for pseudo-random binary code-linear frequency modulation(PRBC-LFM)signals require prior knowledge,are computationally complex,and exhibit poor performance at low signal-to-noise ratios(SNRs).To overcome these problems,a blind parameter estimation method based on a Duffing oscillator array is proposed.A new relationship formula among the state of the Duffing oscillator,the pseudo-random sequence of the PRBC-LFM signal,and the frequency difference between the PRBC-LFM signal and the periodic driving force signal of the Duffing oscillator is derived,providing the theoretical basis for blind parameter estimation.Methods based on amplitude method,short-time Fourier transform method,and power spectrum entropy method are used to binarize the output of the Duffing oscillator array,and their performance is compared.The pseudo-random sequence is estimated using Duffing oscillator array synchronization,and the carrier frequency parameters are obtained by the relational expressions and characteristics of the difference frequency.Simulation results show that this blind estimation method overcomes limitations in prior knowledge and maintains good parameter estimation performance up to an SNR of-35 dB. 展开更多
关键词 Duffing oscillator pseudo-random binary code-linear frequency modulation(PRBC-LFM)signal blind parameter estimation low signal-to-noise ratio(SNR)
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Binary-Sequence Frequency Hopping Communication Method Based on Pseudo-Random Linear Frequency Modulation 认领 引用 被引量：1
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作者 TANG Zhiqiang QUAN Houde +1 位作者 SUN Huixian CUI Peizhang 《Journal of Shanghai Jiaotong university(Science)》 EI 2021年第4期534-542,共9页
To improve the signal detection performance of binary-sequence frequency hopping communication when the complementary channel is jammed, a binary-sequence frequency hopping communication system based on pseudo-random ... To improve the signal detection performance of binary-sequence frequency hopping communication when the complementary channel is jammed, a binary-sequence frequency hopping communication system based on pseudo-random liner frequency modulation (LFM) is proposed. The transmitting end uses the chirp signal to carry out the in-band spread spectrum of the binary-sequence frequency hopping signal, and then sends it out through the radio frequency front end. At the receiving end, the received signal is dehopped and processed by fractional Fourier transform. The source information is obtained by sampling decision. Firstly, a binary-sequence frequency hopping system model based on pseudo-random LFM is constructed. Secondly, the bit error rate expression of anti-partial band jamming and follower jamming under the Rice channel is derived. The results show that this method has at least 5 dB performance gain than binary sequence frequency hopping for different parameter settings under partial band jamming and follower jamming, and the anti-jamming performance is significantly better than the conventional frequency hopping communication. 展开更多
关键词 binary-sequence frequency hopping liner frequency modulation(LFM) fractional fourier transform partial band jamming follower jamming
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Parameter estimation method for a linear frequency modulation signal with a Duffing oscillator based on frequency periodicity 认领 引用
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作者 张宁哲 闫晓鹏 +2 位作者 吕明慧 陈秀梅 黄鼎琨 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第8期237-246,共10页
In view of the complexity of existing linear frequency modulation(LFM)signal parameter estimation methods and the poor antinoise performance and estimation accuracy under a low signal-to-noise ratio(SNR),a parameter e... In view of the complexity of existing linear frequency modulation(LFM)signal parameter estimation methods and the poor antinoise performance and estimation accuracy under a low signal-to-noise ratio(SNR),a parameter estimation method for LFM signals with a Duffing oscillator based on frequency periodicity is proposed in this paper.This method utilizes the characteristic that the output signal of the Duffing oscillator excited by the LFM signal changes periodically with frequency,and the modulation period of the LFM signal is estimated by autocorrelation processing of the output signal of the Duffing oscillator.On this basis,the corresponding relationship between the reference frequency of the frequencyaligned Duffing oscillator and the frequency range of the LFM signal is analyzed by the periodic power spectrum method,and the frequency information of the LFM signal is determined.Simulation results show that this method can achieve high-accuracy parameter estimation for LFM signals at an SNR of-25 dB. 展开更多
关键词 linear frequency modulation(LFM)signal Duffing oscillator frequency periodicity parameter estimation
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An Optoelectronic Pulse Frequency Modulation Circuit for Retinal Prosthesis 认领 引用
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作者 刘金彬 陈弘达 +2 位作者 高鹏 裴为华 隋晓红 《Journal of Semiconductors》 CAS 北大核心 2006年第4期700-704,共5页
A pulse frequency modulation（PFM） circuit for retinal prosthesis,which generates electrical pulses with frequency proportional to the intensity of incident light, is presented. The fundamental characteristic of the ... A pulse frequency modulation（PFM） circuit for retinal prosthesis,which generates electrical pulses with frequency proportional to the intensity of incident light, is presented. The fundamental characteristic of the circuit is described and analyzed. The circuit is realized in 0.6μm CMOS process,and the simulation results testify to the possibility of sub-retinal implantation. 展开更多
关键词 retinal prosthesis sub-retinal implant pulse frequency modulation
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Recognition of Frequency Modulation Signal Using Parameter Invariant Filter 认领 引用
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作者 姚亚峰 陈建文 黄载禄 《Journal of Shanghai University(English Edition)》 2005年第5期415-418,共4页
To classify the frequency modulation signal, this paper employs a parameter invariant filter, which can transfer the frequency modulated information to variety of its envelope, and then extracts the histogram feature ... To classify the frequency modulation signal, this paper employs a parameter invariant filter, which can transfer the frequency modulated information to variety of its envelope, and then extracts the histogram feature to classify the modulation type. This method can efficiently classify the type of a signal such as frequency modulation （FM）, binary frequency shift keyiing （BFSK）, quadrature frequency shift keying （QFSK）, 8-ary frequency shift keying （8FSK）, etc. It can easily be realized and is especially suitable to applications in software radio. 展开更多
关键词 modulation recognition frequency modulation parameter invariant filter histogram.
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Research on the Primary Frequency Modulation Operation of 650MW Nuclear Power Steam Turbine Unit in China 认领 引用
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作者 BAIHao 《外文科技期刊数据库（文摘版）工程技术》 2022年第6期213-218,共6页
Primary frequency regulation is one of the important regulation means to maintain the stable operation of the power grid, and for a single unit, especially the nuclear power unit, the frequency regulation process is a... Primary frequency regulation is one of the important regulation means to maintain the stable operation of the power grid, and for a single unit, especially the nuclear power unit, the frequency regulation process is an unstable factor. With the increasing capacity of nuclear motor assembly machine, it is bound to shoulder the heavy responsibility of peak shaving and frequency modulation. However, its own particularity determines that it cannot be as flexible as thermal power plants and other power plants in terms of frequency modulation, and it is necessary to find a balance between maintaining the stability of the power grid and the safe and stable operation of units. Taking 650MW nuclear power steam turbine unit as an example, this paper introduces and analyzes in detail the control principle, control process, frequency modulation parameter setting of its primary frequency modulation, as well as the adverse effects of reactor protection actions such as reactor over power that may be caused by transient events and primary frequency modulation process. By taking technical measures such as adjusting the mode of primary frequency modulation operation, we can reduce the impact of external network faults on the unit, summarize the experience of transient disposal, and improve the plan, improve the ability of the main control operator to judge and deal with the transient, so as to ensure that the unit can meet the requirements of the primary frequency modulation response of the power grid on the basis of safe and stable operation. 展开更多
关键词 primary frequency modulation nuclear power unit frequency modulation parameters reactor protection
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Measurement of remanent magnetic moment using a torsion pendulum with single frequency modulation method 认领 引用
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作者 乔敏娜 刘鲁华 +4 位作者 蔡柏松 张雅婷 王晴岚 徐家豪 刘祺 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第5期83-87,共5页
In Tian Qin spaceborne gravitational-wave detectors, the stringent requirements on the magnetic cleanliness of the test masses demand the high resolution ground-based characterization measurement of their magnetic pro... In Tian Qin spaceborne gravitational-wave detectors, the stringent requirements on the magnetic cleanliness of the test masses demand the high resolution ground-based characterization measurement of their magnetic properties. Here we present a single frequency modulation method based on a torsion pendulum to measure the remanent magnetic moment mr of 1.1 kg dummy copper test mass, and the measurement result is(6.45 ± 0.04(stat) ± 0.07(syst)) × 10-8A · m2. The measurement precision of the mr is about 0.9 n A · m2, well below the present measurement requirement of Tian Qin. The method is particularly useful for measuring extremely low magnetic properties of the materials for use in the construction of space-borne gravitational wave detection and other precision scientific apparatus. 展开更多
关键词 remanent magnetic moment torsion pendulum single frequency modulation method
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Suppression of Stokes heating processes and improved optomechanical cooling with frequency modulation 认领 引用
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作者 Yang Bao Qinghong Liao +1 位作者 Qingmin Zhao Jing Wu 《Communications in Theoretical Physics》 SCIE CAS CSCD 2022年第4期42-51,共10页
Ground-state cooling of mesoscopic mechanical objects is still a major challenge in the unresolved-sideband regime.We present a frequency modulation(FM)scheme to achieve cooling of the mechanical resonator to its grou... Ground-state cooling of mesoscopic mechanical objects is still a major challenge in the unresolved-sideband regime.We present a frequency modulation(FM)scheme to achieve cooling of the mechanical resonator to its ground-state in a double-cavity optomechanical system containing a mechanical resonator.The mean phonon number is determined by numerically solving a set of differential equations derived from the quantum master equations.Due to efficient suppression of Stokes heating processes in the presence of FM,the ground-state cooling,indicated by numerical calculations,is significantly achievable,regardless of whether in the resolved-sideband regime or the unresolved-sideband regime.Furthermore,by choosing parameters reasonably,the improvement of the quantum cooling limit is found to be capable of being positively correlated with the modulation frequency.This method provides new insight into quantum manipulation and creates more possibilities for applications of quantum devices. 展开更多
关键词 ground-state cooling Stokes heating processes frequency modulation unresolved sideband
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Desired Dynamic Equation for Primary Frequency Modulation Control of Gas Turbines 认领 引用
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作者 Aimin Gao Xiaobo Cui +2 位作者 Guoqiang Yu Jianjun Shu Tianhai Zhang 《Energy Engineering》 EI 2024年第5期1347-1361,共15页
Gas turbines play core roles in clean energy supply and the construction of comprehensive energy systems.The control performance of primary frequency modulation of gas turbines has a great impact on the frequency cont... Gas turbines play core roles in clean energy supply and the construction of comprehensive energy systems.The control performance of primary frequency modulation of gas turbines has a great impact on the frequency control of the power grid.However,there are some control difficulties in the primary frequency modulation control of gas turbines,such as the coupling effect of the fuel control loop and speed control loop,slow tracking speed,and so on.To relieve the abovementioned difficulties,a control strategy based on the desired dynamic equation proportional integral(DDE-PI)is proposed in this paper.Based on the parameter stability region,a parameter tuning procedure is summarized.Simulation is carried out to address the ease of use and simplicity of the proposed tuning method.Finally,DDE-PI is applied to the primary frequency modulation system of an MS6001B heavy-duty gas turbine.The simulation results indicate that the gas turbine with the proposed strategy can obtain the best control performance with a strong ability to deal with system uncertainties.The proposed method shows good engineering application potential. 展开更多
关键词 Gas turbine primary frequency modulation(PFM) desired dynamic equation(DDE) proportion-integral(PI)
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Enhancing quantum temporal steering via frequency modulation 认领 引用
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作者 吴孟凯 程维文 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第5期239-245,共7页
Various strategies have been proposed to harness and protect space-like quantum correlations in different models under decoherence.However,little attention has been given to temporal-like correlations,such as quantum ... Various strategies have been proposed to harness and protect space-like quantum correlations in different models under decoherence.However,little attention has been given to temporal-like correlations,such as quantum temporal steering(TS),in this context.In this work,we investigate TS in a frequency-modulated two-level system coupled to a zero-temperature reservoir in both the weak and strong coupling regimes.We analyze the impact of various frequency-modulated parameters on the behavior of TS and non-Markovian.The results demonstrate that appropriate frequency-modulated parameters can enhance the TS of the two-level system,regardless of whether the system is experiencing Markovian or non-Markovian dynamics.Furthermore,a suitable ratio between modulation strength and frequency(i.e.,all zeroes of the 0th Bessel function J0(δ/?))can significantly enhance TS in the strong coupling regime.These findings indicate that efficient and effective manipulation of quantum TS can be achieved through a frequency-modulated approach. 展开更多
关键词 quantum temporal steering frequency modulation decoherence
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Gauss linear frequency modulation wavelet transforms and its application to seismic phases identification 认领 引用
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作者 刘希强 周惠兰 +3 位作者 曹文海 李红 李永红 季爱东 《Acta Seismologica Sinica(English Edition)》 2002年第6期636-645,共10页
Based on the characteristics of gradual change style seismic signal onset which has more high frequency signal components but less magnitude, this paper selects Gauss linear frequency modulation wavelet as base functi... Based on the characteristics of gradual change style seismic signal onset which has more high frequency signal components but less magnitude, this paper selects Gauss linear frequency modulation wavelet as base function to study the change characteristics of Gauss linear frequency modulation wavelet transform with difference wavelet and signal parameters, analyzes the error origin of seismic phases identification on the basis of Gauss linear frequency modulation wavelet transform, puts forward a kind of new method identifying gradual change style seismic phases with background noise which is called fixed scale wavelet transform ratio, and presents application examples about simulation digital signal and actual seismic phases recording onsets identification. 展开更多
关键词 Gauss linear frequency modulation wavelet wavelet transform gradual change style seismic sig-nal onset identification
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A new method of demodulating the digital frequency modulation signals 认领 引用 被引量：2
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作者 Jin-cai Sun Wei-jie Zhu Yi-yun Sun and Hui Xiao 《Journal of Marine Science and Application》 2003年第2期5-10,共6页
A new method of estimating the frequency-known signals from the strong background noise was presented first. Then the new method was used in the demodulation of the digital frequency modulation (FSK) signals. The new ... A new method of estimating the frequency-known signals from the strong background noise was presented first. Then the new method was used in the demodulation of the digital frequency modulation (FSK) signals. The new demodulation method can complete the demodulation of the FSK signals only with the carrier frequency and without any carrier phase information. The simulation results show that the performance of anti-noise of the new method is better than that of the incoherent demodulation method and the fluctuation of the carrier phase has little effect on the new method. So the new demodulation method has a fine prospect in the practical applications. 展开更多
关键词 digital frequency modulation signals underwater acoustic communications demodulation detection
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Spectrum for Pulse Frequency Modulation 认领 引用 被引量：1
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作者 HUANG Yuan SUN Jianjun 《Semiconductor Photonics and Technology》 1996年第3期194-198,共5页
This paper gives a spectrum expression which is simple and has a clear physical conception for pulse frequency modulation signal, and has been confirmed by an experiment simultaneously.
关键词 Spectral Analysis Pulse Frequency Modulation Modulation Instanta neous Frequency
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Three Dimensional Study of Spectral Response of Polycrystalline Silicon Solar Cells: Vertical Junction Frequency Modulation Scheme 认领 引用
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作者 Nouhou Bako Zeinabou Hawa Ly Diallo +4 位作者 Aminata Gueye Camarat Moustapha Thiam Dan Maza Abouzeidi Madougou Saidou Gregoire Sissoko 《Journal of Energy and Power Engineering》 CAS 2013年第5期903-906,共4页
In this paper, the modeling ofa bifacial polycrystalline silicon solar cells vertical junction is presented. The study in dynamic frequency is limited to wavelengths from 400 nm to 1100 nm. The dependence of solar cel... In this paper, the modeling ofa bifacial polycrystalline silicon solar cells vertical junction is presented. The study in dynamic frequency is limited to wavelengths from 400 nm to 1100 nm. The dependence of solar cell spectral response on wavelengths for several modulation frequencies was evaluated by using solar cell internal quantum efficiency.The objective is to characterize the polycrystalline silicon in 3D. The effect of frequency modulation pulsation on the phase of internal quantum efficiency was presented as well as values of shunt and series resistance for various grains size values. The results show that the value of maximum internal quantum efficiency is about 50% with a wavelength of 0,82 nm and a frequency of 103 rad/s under monochromatic illumination. 展开更多
关键词 Solar cell vertical junction polycrystalline silicon frequency modulation internal quantum efficiency wavelength.
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Strain measurement using frequency modulation fiber optic interferometer 认领 引用
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作者 LIChangchun LUOFei 《Semiconductor Photonics and Technology》 1995年第1期31-34,共4页
The method for measuring the strain of an object using an optical fiber and a frequency modulation(FM) coupled cavity semiconductor laser is proposed.This method uses the coherent FM heterodyne principle of the Michel... The method for measuring the strain of an object using an optical fiber and a frequency modulation(FM) coupled cavity semiconductor laser is proposed.This method uses the coherent FM heterodyne principle of the Michelson interferometer and can avoid the π/2 nonreciprocal phase bias and phase shifting problem existing in general fiber optic interferential sensors, the maximum detection range is limited by the coherent length of the semiconductor laser and its relative factor. 展开更多
关键词 Frequency Modulation Fiber Optic Sensors Semiconductor Lasers Michelson Interferometer
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Ultra-Long Ultra-Broadband Distributed Acoustic Sensing With Zadoff-Chu Nonlinear Frequency Modulation and LEAF 认领 引用
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作者 Rong TANG Sijin ZHENG +5 位作者 Yunhe SONG Zhikai LIU Tianyu HUA Shengtao ZOU Qiang JING Yunjiang RAO 《Photonic Sensors》 SCIE EI CSCD 2026年第1期17-28,共12页
The performances of fiber-optic distributed acoustic sensing(DAS)systems are fundamentally limited by the trade-off between the sensing distance and response bandwidth(RB),constraining the effectiveness of the DAS for... The performances of fiber-optic distributed acoustic sensing(DAS)systems are fundamentally limited by the trade-off between the sensing distance and response bandwidth(RB),constraining the effectiveness of the DAS for long-haul sensing applications greatly.To break such a limitation,this paper proposes a novel Zadoff-Chu(ZC)based nonlinear frequency modulation(ZC-NLFM)scheme that combines the zero-correlation property of the ZC method with the chirp diversity of NLFM.The generated ZC-NLFM pulses exhibit excellent sidelobe and inter-pulse interference suppression,enabling high-sensitivity DAS demodulation even under low signal-to-noise ratio conditions.Furthermore,by employing the large-effective-area fiber(LEAF)with the lower attenuation,higher stimulated Brillouin scattering threshold,and Raman amplification,a wide-frequency-range,long-distance,and low-noise DAS(WLL-DAS)with high strain sensitivity of 94.34 pε/√Hz over a wide RB of up to 7 kHz and an ultralong sensing distance of 148 km at the spatial resolution of 10 m is achieved simultaneously.Compared to the conventional DAS,the proposed WLL-DAS achieves a 22-fold increase in the RB over an ultralong distance of>140 km,significantly extending the performance boundary and application range of the DAS. 展开更多
关键词 Optical fiber sensing distributed acoustic sensing nonlinear frequency modulation
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Exact analytical results for a two-level system driven by a pulse with Lorentzian frequency and sub-Lorentzian amplitude modulations 认领 引用
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作者 Qiong-Tao Xie 《Communications in Theoretical Physics》 SCIE CAS CSCD 2026年第3期65-72,共8页
We investigate the dynamics of a two-level quantum system driven by a laser pulse characterized by Lorentzian frequency and sub-Lorentzian amplitude modulations.Complete analytical solutions,expressed via confluent He... We investigate the dynamics of a two-level quantum system driven by a laser pulse characterized by Lorentzian frequency and sub-Lorentzian amplitude modulations.Complete analytical solutions,expressed via confluent Heun functions,are derived.Our analysis reveals that explicit exact analytical solutions exist under infinite sets of specific parameter conditions.The effects of modulation parameters and initial conditions on the final transition probabilities are examined analytically and numerically.Furthermore,the method is demonstrated to be directly applicable to two closely related models with Lorentzian pulses. 展开更多
关键词 exact analytical solutions Lorentzian frequency modulation sub-Lorentzian amplitude modulation two-level system
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