The heavy-ion accelerator facility(HIAF)under construction in China will produce various stable and intense radioactive beams with energies ranging from MeV/u to GeV/u.The ion-linac(iLinac)accelerator,which will serve...The heavy-ion accelerator facility(HIAF)under construction in China will produce various stable and intense radioactive beams with energies ranging from MeV/u to GeV/u.The ion-linac(iLinac)accelerator,which will serve as the injector for the HIAF,is a superconducting heavy-ion accelerator containing 13 cryomodules.It will operate in either continuous wave mode or pulsed mode,with a beam current ranging from 0.01 to 1 emA.The beam position monitor(BPM)is crucial for this high-beam-power machine,which requires precise beam control and a very small beam loss of less than 1 W/m,especially inside the cryomodules of this unique beam instrument.Nearly 70 BPMs will be installed on the iLinac.New digital beam position and phase measurement(DBPPM)electronics based on a heterogeneous multiprocessing platform system-on-chip(MPSoC)has been developed to provide accurate beam trajectory and phase measurements as well as beam interlocking signals for a fast machine protection system(MPS).The DBPPM comprises an analog front-end(AFE)board in field programmable gate array(FPGA)mezzanine-connector(FMC)form factor,along with a digital signal processing board housed within a “2U 19”chassis.To mitigate radio frequency(RF)leakage effects from high-power RF systems in certain scenarios,beam signals undergo simultaneous processing at both fundamental and second-harmonic frequencies.A dynamic range from-65 dBm to 0 dBm was established to accommodate both weak beam commissioning and high-intensity operational demands.Laboratory tests demonstrated that at input power levels exceeding-45 d Bm,the phase resolution surpasses 0.05°,and the position resolution exceeds 5μm.These results align well with the stipulated measurement requirements.Moreover,the newly developed DBPPM has self-testing and self-calibration functions that are highly helpful for the systematic evaluation of numerous electronic components and fault diagnosis equipment.In addition,the DBPPM electronics implements a 2D nonlinear polynomial correction on the FPGA and can collect accurate real-time position measurements at large beam offsets.This newly developed DBPPM electronics has been applied to several Linac machines,and the results from beam measurements show high performance,good long-term stability,and high reliability.In this paper,a detailed overview of the architecture,performance,and proof-of-principle measurement of the beams is presented.展开更多
Traffic monitoring is of major importance for enforcing traffic management policies.To accomplish this task,the detection of vehicle can be achieved by exploiting image analysis techniques.In this paper,a solution is ...Traffic monitoring is of major importance for enforcing traffic management policies.To accomplish this task,the detection of vehicle can be achieved by exploiting image analysis techniques.In this paper,a solution is presented to obtain various traffic parameters through vehicular video detection system(VVDS).VVDS exploits the algorithm based on virtual loops to detect moving vehicle in real time.This algorithm uses the background differencing method,and vehicles can be detected through luminance difference of pixels between background image and current image.Furthermore a novel technology named as spatio-temporal image sequences analysis is applied to background differencing to improve detection accuracy.Then a hardware implementation of a digital signal processing (DSP) based board is described in detail and the board can simultaneously process four-channel video from different cameras. The benefit of usage of DSP is that images of a roadway can be processed at frame rate due to DSP′s high performance.In the end,VVDS is tested on real-world scenes and experiment results show that the system is both fast and robust to the surveillance of transportation.展开更多
The modified atomic transformations are constructed and proved. On their basis the new complex analytic wavelets are obtained. The proof of the Fourier transforms existence in L~ and L2 on the basis of the theory of a...The modified atomic transformations are constructed and proved. On their basis the new complex analytic wavelets are obtained. The proof of the Fourier transforms existence in L~ and L2 on the basis of the theory of atomic functions （AF） are presented. The numerical experiments of digital time series processing and physical analysis of the results confirm the efficiency of the proposed transforms.展开更多
On the basis of modified atomic transformations the new WA-systems of Kravchenko functions are constructed.As an example the digital processing of time series of the various physical nature processing is considered.Th...On the basis of modified atomic transformations the new WA-systems of Kravchenko functions are constructed.As an example the digital processing of time series of the various physical nature processing is considered.The numerical experiments and physical analysis of the results confirm the efficiency of the proposed WA-systems of Kravchenko functions.展开更多
Chaotic optical communication has shown large potential as a hardware encryption method in the physical layer.As an important figure of merit,the bit rate–distance product of chaotic optical communication has been co...Chaotic optical communication has shown large potential as a hardware encryption method in the physical layer.As an important figure of merit,the bit rate–distance product of chaotic optical communication has been continually improved to 30 Gb/s×340 km,but it is still far from the requirement for a deployed optical fiber communication system,which is beyond 100 Gb/s×1000 km.A chaotic carrier can be considered as an analog signal and suffers from fiber channel impairments,limiting the transmission distance of high-speed chaotic optical communications.To break the limit,we propose and experimentally demonstrate a pilot-based digital signal processing scheme for coherent chaotic optical communication combined with deep-learning-based chaotic synchronization.Both transmission impairment recovery and chaotic synchronization are realized in the digital domain.The frequency offset of the lasers is accurately estimated and compensated by determining the location of the pilot tone in the frequency domain,and the equalization and phase noise compensation are jointly performed by the least mean square algorithm through the time domain pilot symbols.Using the proposed method,100 Gb∕s chaotically encrypted quadrature phase-shift keying(QPSK)signal over 800 km single-mode fiber(SMF)transmission is experimentally demonstrated.In order to enhance security,40 Gb∕s real-time chaotically encrypted QPSK signal over 800 km SMF transmission is realized by inserting pilot symbols and tone in a field-programmable gate array.This method provides a feasible approach to promote the practical application of chaotic optical communications and guarantees the high security of chaotic encryption.展开更多
Based on digital signal processing theory,a novel method of designing optical notch filter is proposed for Mach-Zehnder interferometer with cascaded optical fiber rings coupled structure.The method is simple and effec...Based on digital signal processing theory,a novel method of designing optical notch filter is proposed for Mach-Zehnder interferometer with cascaded optical fiber rings coupled structure.The method is simple and effective,and it can be used to implement the designing of the optical notch filter which has arbitrary number of notch points in one free spectrum range(FSR).A design example of notch filter based on cascaded single-fiber-rings is given.On this basis,an improved cascaded double-fiber-rings structure is presented to eliminate the effect of phase shift caused by the single-fiber-ring structure.This new structure can improve the stability and applicability of system.The change of output intensity spectrum is finally investigated for each design parameter and the tuning characteristics of the notch filter are also discussed.展开更多
In this paper, we investigate advanced digital signal process ing （DSP） at the transmitter and receiver side for signal pre equalization and postequalization in order to improve spec trum efficiency （SE） and trans...In this paper, we investigate advanced digital signal process ing （DSP） at the transmitter and receiver side for signal pre equalization and postequalization in order to improve spec trum efficiency （SE） and transmission distance in an optical access network. A novel DSP scheme for this optical super Nyquist filtering 9 Quadrature Amplitude Modulation （9 QAM） like signals based on muhimodulus equalization with out post filtering is proposed. This scheme recovers the Ny quist filtered Quadrature PhaseShift Keying （QPSK） signal to a 9QAMlike one. With this technique, SE can be increased to 4 b/s/Hz for QPSK signals. A novel digital superNyquist signal generation scheme is also proposed to further suppress the Nyquist signal bandwidth and reduce channel crosstalk without the need for optical prefiltering. Only optical cou plers are needed for superNyquist wavelengthdivisionmulti plexing （WDM） channel multiplexing. We extend the DSP for shorthaul optical transmission networks by using highorder QAMs. We propose a highspeed Can＇ierless Amplitude/Phase 64 QAM （CAP64 QAM） system using directly modulated la ser （DML） based on direct detection and digital equalization. Decisiondirected least mean square is used to equalize the CAP64QAM. Using this scheme, we generate and transmit up to 60 Gbit/s CAP64QAM over 20 km standard single mode fiber based on the DML and direct detection. Finally, several key problems are solved for real time orthogonalfre quencydivisionmultiplexing （OFDM） signal transmission aml processing. With coherent detection, up to 100 Glfit/s 16 QAMOFDM realtime transmission is possible.展开更多
A discrete model reference adaptive controller of robot arm is obtained by integrating the reduced dynamic model of robot, model reference adaptive control （MRAC） and digital signal processing （DSP） computer syste...A discrete model reference adaptive controller of robot arm is obtained by integrating the reduced dynamic model of robot, model reference adaptive control （MRAC） and digital signal processing （DSP） computer system into an electromechanical system. With the DSP computer system, the control signal of each joint of the robot arm can be processed in real time and independently. The simulation and experiment results show that with the control strategy, the robot achieved a good trajectory following precision, a good decoupling performance and a high real-time adaptivity.展开更多
In recent years, explosively increasing data traffic has been boosting the con?tinuous demand of high speed optical interconnection inside or among data centers, high performance computers and even consumer electronic...In recent years, explosively increasing data traffic has been boosting the con?tinuous demand of high speed optical interconnection inside or among data centers, high performance computers and even consumer electronics. To pursue the improved intercon?nection performance of capacity, energy efficiency and simplicity, effective approaches are demonstrated including particularly advanced digital signal processing (DSP) meth?ods. In this paper, we present a review about the enabling adaptive DSP methods for opti?cal interconnection applications, and a detailed summary of our recent and ongoing works in this field. In brief, our works focus on dealing with the specific issues for short-reach interconnection scenarios with adaptive operation, including signal-to-noise-ratio (SNR) limitation, level nonlinearity distortion, energy efficiency consideration and the de?cision precision.展开更多
This paper proposes the design and development of virtual experimental projects in the Digital Signal Processing course,using MATLAB,Proteus,and CCS platforms to develop a library of typical experimental cases for bio...This paper proposes the design and development of virtual experimental projects in the Digital Signal Processing course,using MATLAB,Proteus,and CCS platforms to develop a library of typical experimental cases for biomedical engineering majors and discusses the design process.Based on these typical cases,this paper explores the secondary design for innovative engineering practice case teaching,which can promote students’understanding and mastery of digital signal processing theories,algorithms,and technologies in an intuitive,flexible,and efficient way;quickly build new innovative engineering case models and further cultivate students’engineering application ability as well as innovative thinking.展开更多
We present an all-digital demodulation system of interferometric fiber optic sensor based on an improved arctangent-differential-self-multiplying(arctan-DSM)algorithm.The total harmonic distortion(THD)and the light in...We present an all-digital demodulation system of interferometric fiber optic sensor based on an improved arctangent-differential-self-multiplying(arctan-DSM)algorithm.The total harmonic distortion(THD)and the light intensity disturbance(LID)are also suppressed,the same as those in the traditional arctan-DSM algorithm.Moreover,the lowest sampling frequency is also reduced by introducing anti-aliasing filter,so the occupation of the system memory is reduced.The simulations show that the improved algorithm can correctly demodulate cosine signal and chirp signal with lower sampling frequency.展开更多
This article deals with two important issues in digital filter implementation： roundoff noise and limit cycles. A novel class of robust state-space realizations, called normal realizations, is derived and characteriz...This article deals with two important issues in digital filter implementation： roundoff noise and limit cycles. A novel class of robust state-space realizations, called normal realizations, is derived and characterized. It is seen that these realizations are free of limit cycles. Another interesting property of the normal realizations is that they yield a minimal error propagation gain. The optimal realization problem, defined as to find those normal realizations that minimize roundoff noise gain, is formulated and solved analytically. A design example is presented to demonstrate the behavior of the optimal normal realizations and to compare them with several well-known digital filter realizations in terms of minimizing the roundoff noise and the error propagation.展开更多
Optical fiber acceleration seismometer as an important instrument can offer high sensitivity, anti-jamming and non-touched advantage which has an extensive application field. Its signal processing ability will decide ...Optical fiber acceleration seismometer as an important instrument can offer high sensitivity, anti-jamming and non-touched advantage which has an extensive application field. Its signal processing ability will decide whole system’s performance to some extent because it will affect directly the factors such as resolving power, precision and dynamic range. The signal processing is usually realized by analog circuits which was more inferior in stability, flexibility and anti-jamming to digital processing system. A digital processing system of optical fiber acceleration seismometer has been designed based on the embedded system design scheme. Synthetic-heterodyne demodulation has been studied, and signal processing has been realized. The double processors of ARM and DSP are employed to implement respectively the system control and signal processing, and to provide the output interfaces such as LCD, DAC and Ethernet interface. This system can vary with the measured signal in real time and linearly, and its work frequency bandwidth is between 10Hz and 1kHz. The system has better anti-jamming ability and can work normally when the SNR is 40dB.展开更多
The absolute delay caused by equipment of radio navigation satellite service (RNSS) signal channel must be calibrated in the application of positioning. The measurement accuracy of absolute delay will affect the posit...The absolute delay caused by equipment of radio navigation satellite service (RNSS) signal channel must be calibrated in the application of positioning. The measurement accuracy of absolute delay will affect the positioning precision of RNSS user. An absolute delay measurement technique using digital envelope detection was developed for RNSS signal transmission channel. The RNSS transmission signal of navigation satellite and the one pulse per second (1PPS)generated by satellite time keeping system were sampled synchronously. With sampling data of 1PPS,the reference point of the absolute delay can be decided at first,and then sampling data of RNSS transmission signal were truncated. The truncated data were processed using digital envelop detection algorithm to search the phase converting points of RNSS signal. Finally,the absolute delay of RNSS signal transmitting channel was calculated. Uncertainty of measurement with proposed technique is lower than 0. 2 ns as the sampling frequency is 10 GHz.展开更多
This paper introduced a welding machine for GMAW using digital controlling method based on DSP (Digital Signal Process). By means of flexible programming according to welding technologies and experiences the suitable ...This paper introduced a welding machine for GMAW using digital controlling method based on DSP (Digital Signal Process). By means of flexible programming according to welding technologies and experiences the suitable characteristics of welding machine, such as line compensation, welding voltage and current feedback, wire-feed driving, SCR trigging and so on, can be controlled and self-adjusted using digital signals. Through the designing based on DSP it is put out that the traditional hardware of control circuit is decreased greatly which can enhance the stability and reliability of welding machine. Finally, the welding experiment using CO 2 shielding gas proves that the welding process is stable.展开更多
Three-dimensional (3-D) matched filtering has been suggested as a powerful processing technique for detecting weak, moving IR point target immersed in a noisy field. Based on the theory of the 3-D matched filtering an...Three-dimensional (3-D) matched filtering has been suggested as a powerful processing technique for detecting weak, moving IR point target immersed in a noisy field. Based on the theory of the 3-D matched filtering and the optimal linear processing, the optimal point target detector is being analyzed in this paper. The performance of the detector is introduced in detail. The results provide a standard reference to evaluate the performance of any other point target detection algorithms.展开更多
Mathematical models can produce desired dynamics and statistical properties with the insertion of suitable nonlinear terms,while energy characteristics are crucial for practical application because any hardware realiz...Mathematical models can produce desired dynamics and statistical properties with the insertion of suitable nonlinear terms,while energy characteristics are crucial for practical application because any hardware realizations of nonlinear systems are relative to energy flow.The involvement of memristive terms relative to memristors enables multistability and initial-dependent property in memristive systems.In this study,two kinds of memristors are used to couple a capacitor or an inductor,along with a nonlinear resistor,to build different neural circuits.The corresponding circuit equations are derived to develop two different types of memristive oscillators,which are further converted into two kinds of memristive maps after linear transformation.The Hamilton energy function for memristive oscillators is obtained by applying the Helmholz theorem or by mapping from the field energy of the memristive circuits.The Hamilton energy functions for both memristive maps are obtained by replacing the gains and discrete variables for the memristive oscillator with the corresponding parameters and variables.The two memristive maps have rich dynamic behaviors including coherence resonance under noisy excitation,and an adaptive growth law for parameters is presented to express the self-adaptive property of the memristive maps.A digital signal process(DSP)platform is used to verify these results.Our scheme will provide a theoretical basis and experimental guidance for oscillator-to-map transformation and discrete map-energy calculation.展开更多
Programmable photonic waveguide meshes can be programmed into many different circuit topologies and thereby provide a variety of functions.Due to the complexity of the signal routing in a general mesh,a particular syn...Programmable photonic waveguide meshes can be programmed into many different circuit topologies and thereby provide a variety of functions.Due to the complexity of the signal routing in a general mesh,a particular synthesis algorithm often only accounts for a specific function with a specific cell configuration.In this paper,we try to synthesize the programmable waveguide mesh to support multiple configurations with a more general digital signal processing platform.To show the feasibility of this technique,photonic waveguide meshes in different configurations(square,triangular and hexagonal meshes)are designed to realize optical signal interleaving with arbitrary duty cycles.The digital signal processing(DSP)approach offers an effective pathway for the establishment of a general design platform for the software-defined programmable photonic integrated circuits.The use of well-developed DSP techniques and algorithms establishes a link between optical and electrical signals and makes it convenient to realize the computer-aided design of optics–electronics hybrid systems.展开更多
The principle and charecteristics of verious digital optical signal amplifiers using Er doped fiber optical bistability devices have been discussed. Optical signal gain and its variation with the parameters of the de...The principle and charecteristics of verious digital optical signal amplifiers using Er doped fiber optical bistability devices have been discussed. Optical signal gain and its variation with the parameters of the devices with constant or pulse optical bias have been calculated, and the design principle of those devices has been given.展开更多
Four-level pulse amplitude modulation(PAM4)signals,recognized for enhanced energy efficiency and spectral utilization compared with non-return-to-zero(NRZ)counterparts,have been adopted in multiple high-speed serializ...Four-level pulse amplitude modulation(PAM4)signals,recognized for enhanced energy efficiency and spectral utilization compared with non-return-to-zero(NRZ)counterparts,have been adopted in multiple high-speed serializer/deserializer(SerDes)standards,but NRZ modulation remains predominant in industrial applications.This paper introduces a UMC 28 nm CMOS-based parallel configurable forward feedback equalization(FFE)dual-mode high-speed SerDes transmitter supporting 7-bit resolution with data rates of 56 Gb∙s^(-1)NRZ and 112 Gb∙s^(-1)PAM4,utilizing a hybrid architecture that integrates digital signal processing(DSP)with digital-to-analog conversion(DAC).The design processes parallel input signals and eight stored 8-bit tap coefficients through a configurable FFE multiplier module and parallel carry adder module,while achieving low-power serialization via low-speed 16∶4 multiplexers(MUXs)with two different 2∶1 MUXs and high-speed 4∶1 MUXs.A source series termination(SST)output network structure enhances lower power dissipation and higher output swing.Simulation results show that,under a 1.05 V supply voltage and a channel loss of 19.21 dB at 28 GHz,the output 56 Gb∙s^(-1)NRZ eye diagram has an eye height of 70.11 mV and an eye width of 12.16 ps(0.68 UI).The output 112 Gb∙s^(-1)PAM4 eye diagram has an eye height of 20.07 mV and an eye width of 7.49 ps(0.42 UI).The layout area of the dual-mode transmitter is 0.079 mm^(2),and the total circuit power consumption is 74.48 mW(energy efficiency is 1.33/0.67 pJ∙bit-1).展开更多
基金supported by the National Natural Science Foundation of China(No.11975290)。
文摘The heavy-ion accelerator facility(HIAF)under construction in China will produce various stable and intense radioactive beams with energies ranging from MeV/u to GeV/u.The ion-linac(iLinac)accelerator,which will serve as the injector for the HIAF,is a superconducting heavy-ion accelerator containing 13 cryomodules.It will operate in either continuous wave mode or pulsed mode,with a beam current ranging from 0.01 to 1 emA.The beam position monitor(BPM)is crucial for this high-beam-power machine,which requires precise beam control and a very small beam loss of less than 1 W/m,especially inside the cryomodules of this unique beam instrument.Nearly 70 BPMs will be installed on the iLinac.New digital beam position and phase measurement(DBPPM)electronics based on a heterogeneous multiprocessing platform system-on-chip(MPSoC)has been developed to provide accurate beam trajectory and phase measurements as well as beam interlocking signals for a fast machine protection system(MPS).The DBPPM comprises an analog front-end(AFE)board in field programmable gate array(FPGA)mezzanine-connector(FMC)form factor,along with a digital signal processing board housed within a “2U 19”chassis.To mitigate radio frequency(RF)leakage effects from high-power RF systems in certain scenarios,beam signals undergo simultaneous processing at both fundamental and second-harmonic frequencies.A dynamic range from-65 dBm to 0 dBm was established to accommodate both weak beam commissioning and high-intensity operational demands.Laboratory tests demonstrated that at input power levels exceeding-45 d Bm,the phase resolution surpasses 0.05°,and the position resolution exceeds 5μm.These results align well with the stipulated measurement requirements.Moreover,the newly developed DBPPM has self-testing and self-calibration functions that are highly helpful for the systematic evaluation of numerous electronic components and fault diagnosis equipment.In addition,the DBPPM electronics implements a 2D nonlinear polynomial correction on the FPGA and can collect accurate real-time position measurements at large beam offsets.This newly developed DBPPM electronics has been applied to several Linac machines,and the results from beam measurements show high performance,good long-term stability,and high reliability.In this paper,a detailed overview of the architecture,performance,and proof-of-principle measurement of the beams is presented.
文摘Traffic monitoring is of major importance for enforcing traffic management policies.To accomplish this task,the detection of vehicle can be achieved by exploiting image analysis techniques.In this paper,a solution is presented to obtain various traffic parameters through vehicular video detection system(VVDS).VVDS exploits the algorithm based on virtual loops to detect moving vehicle in real time.This algorithm uses the background differencing method,and vehicles can be detected through luminance difference of pixels between background image and current image.Furthermore a novel technology named as spatio-temporal image sequences analysis is applied to background differencing to improve detection accuracy.Then a hardware implementation of a digital signal processing (DSP) based board is described in detail and the board can simultaneously process four-channel video from different cameras. The benefit of usage of DSP is that images of a roadway can be processed at frame rate due to DSP′s high performance.In the end,VVDS is tested on real-world scenes and experiment results show that the system is both fast and robust to the surveillance of transportation.
文摘The modified atomic transformations are constructed and proved. On their basis the new complex analytic wavelets are obtained. The proof of the Fourier transforms existence in L~ and L2 on the basis of the theory of atomic functions （AF） are presented. The numerical experiments of digital time series processing and physical analysis of the results confirm the efficiency of the proposed transforms.
基金Russian Foundation for Basic Research(RFBR)(No.12-02-90425)
文摘On the basis of modified atomic transformations the new WA-systems of Kravchenko functions are constructed.As an example the digital processing of time series of the various physical nature processing is considered.The numerical experiments and physical analysis of the results confirm the efficiency of the proposed WA-systems of Kravchenko functions.
基金supported by the National Nature Science Foundation of China (Grant No.62025503).
文摘Chaotic optical communication has shown large potential as a hardware encryption method in the physical layer.As an important figure of merit,the bit rate–distance product of chaotic optical communication has been continually improved to 30 Gb/s×340 km,but it is still far from the requirement for a deployed optical fiber communication system,which is beyond 100 Gb/s×1000 km.A chaotic carrier can be considered as an analog signal and suffers from fiber channel impairments,limiting the transmission distance of high-speed chaotic optical communications.To break the limit,we propose and experimentally demonstrate a pilot-based digital signal processing scheme for coherent chaotic optical communication combined with deep-learning-based chaotic synchronization.Both transmission impairment recovery and chaotic synchronization are realized in the digital domain.The frequency offset of the lasers is accurately estimated and compensated by determining the location of the pilot tone in the frequency domain,and the equalization and phase noise compensation are jointly performed by the least mean square algorithm through the time domain pilot symbols.Using the proposed method,100 Gb∕s chaotically encrypted quadrature phase-shift keying(QPSK)signal over 800 km single-mode fiber(SMF)transmission is experimentally demonstrated.In order to enhance security,40 Gb∕s real-time chaotically encrypted QPSK signal over 800 km SMF transmission is realized by inserting pilot symbols and tone in a field-programmable gate array.This method provides a feasible approach to promote the practical application of chaotic optical communications and guarantees the high security of chaotic encryption.
基金supported by the National Natural Science Foundation of China (No.10804070)the Innovation Program of Shanghai Municipal Education Commission (No.09YZ06)Shanghai Leading Academic Discipline Project (No.S30108)
文摘Based on digital signal processing theory,a novel method of designing optical notch filter is proposed for Mach-Zehnder interferometer with cascaded optical fiber rings coupled structure.The method is simple and effective,and it can be used to implement the designing of the optical notch filter which has arbitrary number of notch points in one free spectrum range(FSR).A design example of notch filter based on cascaded single-fiber-rings is given.On this basis,an improved cascaded double-fiber-rings structure is presented to eliminate the effect of phase shift caused by the single-fiber-ring structure.This new structure can improve the stability and applicability of system.The change of output intensity spectrum is finally investigated for each design parameter and the tuning characteristics of the notch filter are also discussed.
基金supported by the High Technology Research and Development Program of China("863"Program)under Grant No.2012AA011303 and 2013AA010501National Nature Science Foundation of China under Grant No.61325002
文摘In this paper, we investigate advanced digital signal process ing （DSP） at the transmitter and receiver side for signal pre equalization and postequalization in order to improve spec trum efficiency （SE） and transmission distance in an optical access network. A novel DSP scheme for this optical super Nyquist filtering 9 Quadrature Amplitude Modulation （9 QAM） like signals based on muhimodulus equalization with out post filtering is proposed. This scheme recovers the Ny quist filtered Quadrature PhaseShift Keying （QPSK） signal to a 9QAMlike one. With this technique, SE can be increased to 4 b/s/Hz for QPSK signals. A novel digital superNyquist signal generation scheme is also proposed to further suppress the Nyquist signal bandwidth and reduce channel crosstalk without the need for optical prefiltering. Only optical cou plers are needed for superNyquist wavelengthdivisionmulti plexing （WDM） channel multiplexing. We extend the DSP for shorthaul optical transmission networks by using highorder QAMs. We propose a highspeed Can＇ierless Amplitude/Phase 64 QAM （CAP64 QAM） system using directly modulated la ser （DML） based on direct detection and digital equalization. Decisiondirected least mean square is used to equalize the CAP64QAM. Using this scheme, we generate and transmit up to 60 Gbit/s CAP64QAM over 20 km standard single mode fiber based on the DML and direct detection. Finally, several key problems are solved for real time orthogonalfre quencydivisionmultiplexing （OFDM） signal transmission aml processing. With coherent detection, up to 100 Glfit/s 16 QAMOFDM realtime transmission is possible.
文摘A discrete model reference adaptive controller of robot arm is obtained by integrating the reduced dynamic model of robot, model reference adaptive control （MRAC） and digital signal processing （DSP） computer system into an electromechanical system. With the DSP computer system, the control signal of each joint of the robot arm can be processed in real time and independently. The simulation and experiment results show that with the control strategy, the robot achieved a good trajectory following precision, a good decoupling performance and a high real-time adaptivity.
基金This work was supported by National Natural Science Foundation of Chi⁃na(NSFC)under Grant Nos.61935011,61875124 and 61875049.
文摘In recent years, explosively increasing data traffic has been boosting the con?tinuous demand of high speed optical interconnection inside or among data centers, high performance computers and even consumer electronics. To pursue the improved intercon?nection performance of capacity, energy efficiency and simplicity, effective approaches are demonstrated including particularly advanced digital signal processing (DSP) meth?ods. In this paper, we present a review about the enabling adaptive DSP methods for opti?cal interconnection applications, and a detailed summary of our recent and ongoing works in this field. In brief, our works focus on dealing with the specific issues for short-reach interconnection scenarios with adaptive operation, including signal-to-noise-ratio (SNR) limitation, level nonlinearity distortion, energy efficiency consideration and the de?cision precision.
基金the 2021 Experimental Teaching Reform Project of Shanghai University of Medicine&Health Sciences“Digital Signal Processing Course Design”(Project Number:JG(21)04-B4-02).
文摘This paper proposes the design and development of virtual experimental projects in the Digital Signal Processing course,using MATLAB,Proteus,and CCS platforms to develop a library of typical experimental cases for biomedical engineering majors and discusses the design process.Based on these typical cases,this paper explores the secondary design for innovative engineering practice case teaching,which can promote students’understanding and mastery of digital signal processing theories,algorithms,and technologies in an intuitive,flexible,and efficient way;quickly build new innovative engineering case models and further cultivate students’engineering application ability as well as innovative thinking.
文摘We present an all-digital demodulation system of interferometric fiber optic sensor based on an improved arctangent-differential-self-multiplying(arctan-DSM)algorithm.The total harmonic distortion(THD)and the light intensity disturbance(LID)are also suppressed,the same as those in the traditional arctan-DSM algorithm.Moreover,the lowest sampling frequency is also reduced by introducing anti-aliasing filter,so the occupation of the system memory is reduced.The simulations show that the improved algorithm can correctly demodulate cosine signal and chirp signal with lower sampling frequency.
基金the National Nature Science Foundation of China (60774021)
文摘This article deals with two important issues in digital filter implementation： roundoff noise and limit cycles. A novel class of robust state-space realizations, called normal realizations, is derived and characterized. It is seen that these realizations are free of limit cycles. Another interesting property of the normal realizations is that they yield a minimal error propagation gain. The optimal realization problem, defined as to find those normal realizations that minimize roundoff noise gain, is formulated and solved analytically. A design example is presented to demonstrate the behavior of the optimal normal realizations and to compare them with several well-known digital filter realizations in terms of minimizing the roundoff noise and the error propagation.
文摘Optical fiber acceleration seismometer as an important instrument can offer high sensitivity, anti-jamming and non-touched advantage which has an extensive application field. Its signal processing ability will decide whole system’s performance to some extent because it will affect directly the factors such as resolving power, precision and dynamic range. The signal processing is usually realized by analog circuits which was more inferior in stability, flexibility and anti-jamming to digital processing system. A digital processing system of optical fiber acceleration seismometer has been designed based on the embedded system design scheme. Synthetic-heterodyne demodulation has been studied, and signal processing has been realized. The double processors of ARM and DSP are employed to implement respectively the system control and signal processing, and to provide the output interfaces such as LCD, DAC and Ethernet interface. This system can vary with the measured signal in real time and linearly, and its work frequency bandwidth is between 10Hz and 1kHz. The system has better anti-jamming ability and can work normally when the SNR is 40dB.
基金National Science and Technology Major Project of China(No.DHZX01A02004)
文摘The absolute delay caused by equipment of radio navigation satellite service (RNSS) signal channel must be calibrated in the application of positioning. The measurement accuracy of absolute delay will affect the positioning precision of RNSS user. An absolute delay measurement technique using digital envelope detection was developed for RNSS signal transmission channel. The RNSS transmission signal of navigation satellite and the one pulse per second (1PPS)generated by satellite time keeping system were sampled synchronously. With sampling data of 1PPS,the reference point of the absolute delay can be decided at first,and then sampling data of RNSS transmission signal were truncated. The truncated data were processed using digital envelop detection algorithm to search the phase converting points of RNSS signal. Finally,the absolute delay of RNSS signal transmitting channel was calculated. Uncertainty of measurement with proposed technique is lower than 0. 2 ns as the sampling frequency is 10 GHz.
文摘This paper introduced a welding machine for GMAW using digital controlling method based on DSP (Digital Signal Process). By means of flexible programming according to welding technologies and experiences the suitable characteristics of welding machine, such as line compensation, welding voltage and current feedback, wire-feed driving, SCR trigging and so on, can be controlled and self-adjusted using digital signals. Through the designing based on DSP it is put out that the traditional hardware of control circuit is decreased greatly which can enhance the stability and reliability of welding machine. Finally, the welding experiment using CO 2 shielding gas proves that the welding process is stable.
文摘Three-dimensional (3-D) matched filtering has been suggested as a powerful processing technique for detecting weak, moving IR point target immersed in a noisy field. Based on the theory of the 3-D matched filtering and the optimal linear processing, the optimal point target detector is being analyzed in this paper. The performance of the detector is introduced in detail. The results provide a standard reference to evaluate the performance of any other point target detection algorithms.
基金supported by the National Natural Science Foundation of China(No.12072139).
文摘Mathematical models can produce desired dynamics and statistical properties with the insertion of suitable nonlinear terms,while energy characteristics are crucial for practical application because any hardware realizations of nonlinear systems are relative to energy flow.The involvement of memristive terms relative to memristors enables multistability and initial-dependent property in memristive systems.In this study,two kinds of memristors are used to couple a capacitor or an inductor,along with a nonlinear resistor,to build different neural circuits.The corresponding circuit equations are derived to develop two different types of memristive oscillators,which are further converted into two kinds of memristive maps after linear transformation.The Hamilton energy function for memristive oscillators is obtained by applying the Helmholz theorem or by mapping from the field energy of the memristive circuits.The Hamilton energy functions for both memristive maps are obtained by replacing the gains and discrete variables for the memristive oscillator with the corresponding parameters and variables.The two memristive maps have rich dynamic behaviors including coherence resonance under noisy excitation,and an adaptive growth law for parameters is presented to express the self-adaptive property of the memristive maps.A digital signal process(DSP)platform is used to verify these results.Our scheme will provide a theoretical basis and experimental guidance for oscillator-to-map transformation and discrete map-energy calculation.
文摘Programmable photonic waveguide meshes can be programmed into many different circuit topologies and thereby provide a variety of functions.Due to the complexity of the signal routing in a general mesh,a particular synthesis algorithm often only accounts for a specific function with a specific cell configuration.In this paper,we try to synthesize the programmable waveguide mesh to support multiple configurations with a more general digital signal processing platform.To show the feasibility of this technique,photonic waveguide meshes in different configurations(square,triangular and hexagonal meshes)are designed to realize optical signal interleaving with arbitrary duty cycles.The digital signal processing(DSP)approach offers an effective pathway for the establishment of a general design platform for the software-defined programmable photonic integrated circuits.The use of well-developed DSP techniques and algorithms establishes a link between optical and electrical signals and makes it convenient to realize the computer-aided design of optics–electronics hybrid systems.
文摘The principle and charecteristics of verious digital optical signal amplifiers using Er doped fiber optical bistability devices have been discussed. Optical signal gain and its variation with the parameters of the devices with constant or pulse optical bias have been calculated, and the design principle of those devices has been given.
基金Supported by the National Key R&D Program Broadband Communications and New Network Key Special Project(No.2019YFB1803600).
文摘Four-level pulse amplitude modulation(PAM4)signals,recognized for enhanced energy efficiency and spectral utilization compared with non-return-to-zero(NRZ)counterparts,have been adopted in multiple high-speed serializer/deserializer(SerDes)standards,but NRZ modulation remains predominant in industrial applications.This paper introduces a UMC 28 nm CMOS-based parallel configurable forward feedback equalization(FFE)dual-mode high-speed SerDes transmitter supporting 7-bit resolution with data rates of 56 Gb∙s^(-1)NRZ and 112 Gb∙s^(-1)PAM4,utilizing a hybrid architecture that integrates digital signal processing(DSP)with digital-to-analog conversion(DAC).The design processes parallel input signals and eight stored 8-bit tap coefficients through a configurable FFE multiplier module and parallel carry adder module,while achieving low-power serialization via low-speed 16∶4 multiplexers(MUXs)with two different 2∶1 MUXs and high-speed 4∶1 MUXs.A source series termination(SST)output network structure enhances lower power dissipation and higher output swing.Simulation results show that,under a 1.05 V supply voltage and a channel loss of 19.21 dB at 28 GHz,the output 56 Gb∙s^(-1)NRZ eye diagram has an eye height of 70.11 mV and an eye width of 12.16 ps(0.68 UI).The output 112 Gb∙s^(-1)PAM4 eye diagram has an eye height of 20.07 mV and an eye width of 7.49 ps(0.42 UI).The layout area of the dual-mode transmitter is 0.079 mm^(2),and the total circuit power consumption is 74.48 mW(energy efficiency is 1.33/0.67 pJ∙bit-1).
