ISSN 
1997 Vol. 26, No. 1
1997, 26(1): 2-7.
Abstract:
This paper studies multimedia transport and control techniques of multimedia integrated services communication system (MISCS) based on a standard LAN.The function design of MISCS is developed,and the architecture of hardware is introduced.The design of multimedia data stream is emphasized and the control techniques are studied to satisfy quality of service in video,image and file transfer.This paper also analyses delay jitters and corresponding control schemes in voice transfer.Finally,an experiment system is revealed.
This paper studies multimedia transport and control techniques of multimedia integrated services communication system (MISCS) based on a standard LAN.The function design of MISCS is developed,and the architecture of hardware is introduced.The design of multimedia data stream is emphasized and the control techniques are studied to satisfy quality of service in video,image and file transfer.This paper also analyses delay jitters and corresponding control schemes in voice transfer.Finally,an experiment system is revealed.
1997, 26(1): 8-12.
Abstract:
The use of burst adaptive frequency selection(BAFS) in HF communication network is discussed in this paper.The specifications of BAFS and the advantages of its use in HF network are analyzed.The protocol of BAFS in HF network is designed only partly according to MIL-STD-188-141A,because the basic characteristics of BAFS and CAFS(Continuous AFS) are quite different.Then the performance of this protocol is simultaneously evaluated.Also some schemes optimal in different releases are discussed.
The use of burst adaptive frequency selection(BAFS) in HF communication network is discussed in this paper.The specifications of BAFS and the advantages of its use in HF network are analyzed.The protocol of BAFS in HF network is designed only partly according to MIL-STD-188-141A,because the basic characteristics of BAFS and CAFS(Continuous AFS) are quite different.Then the performance of this protocol is simultaneously evaluated.Also some schemes optimal in different releases are discussed.
1997, 26(1): 13-16.
Abstract:
The goal in designing a GPS code pseudorange smoothing algorithm is to smooth the random noise of the code pseudorange by means of the carrier observables and to improve the positioning accuracy when the requirement for real-time kinematic point determination is satisfied.The performance of smoothing algorithm is dominated by three factors of the receiver performance,the choice of weight factor,and the recursive time.Theoretic discussion of evaluation of the smoothing algorithm is made in this paper.And a smoothing algorithm with optimal weight factor is given here,which has the fastest noise reduction performance.
The goal in designing a GPS code pseudorange smoothing algorithm is to smooth the random noise of the code pseudorange by means of the carrier observables and to improve the positioning accuracy when the requirement for real-time kinematic point determination is satisfied.The performance of smoothing algorithm is dominated by three factors of the receiver performance,the choice of weight factor,and the recursive time.Theoretic discussion of evaluation of the smoothing algorithm is made in this paper.And a smoothing algorithm with optimal weight factor is given here,which has the fastest noise reduction performance.
1997, 26(1): 17-20.
Abstract:
In this paper,the bit error rate of a synchronous CDMA communication system with a pre-decorrelating technique over non-seletive fading channels is considered in additive white noise environment.Results show that the performance become bed because of fading.The bit error rate grows with the increase of the amplitude of non-direct signals.
In this paper,the bit error rate of a synchronous CDMA communication system with a pre-decorrelating technique over non-seletive fading channels is considered in additive white noise environment.Results show that the performance become bed because of fading.The bit error rate grows with the increase of the amplitude of non-direct signals.
1997, 26(1): 21-23.
Abstract:
Synthetic aperture radar (SAR) produces high bit flow and large amount of data.The compression of data will benefit both data communication and data storage.In this paper,the polar quantization methods are used for SAR raw data compression,the polar quantization methods are introduced,the block adaptive quantization is combined with the polar quantization.At last,the figures of polar quantizers are tested by X-SAR raw data and compared with the quadratic quatizer.
Synthetic aperture radar (SAR) produces high bit flow and large amount of data.The compression of data will benefit both data communication and data storage.In this paper,the polar quantization methods are used for SAR raw data compression,the polar quantization methods are introduced,the block adaptive quantization is combined with the polar quantization.At last,the figures of polar quantizers are tested by X-SAR raw data and compared with the quadratic quatizer.
1997, 26(1): 24-28.
Abstract:
QR decomposition LS algorithm (QRD) is a widely used algorithm for adaptive arrays recently,which has good numerical stability and can be easily mapped to Systolic structure for parallel processing.However,for full adaptive array where optimal weights are needed,this method typically requries three Systolic modulars to produce optimal weight.This paper presents a new method to solve the nulling problem of a full adaptive array using inverse QR decomposition LS algorithm (IQRD) and its Systolic implementation.It can easily obtain optimal weight vector using only one Systolic array.Since it still directly deals with the input data matrix and is based on unitary transformation,the IQRD algorithm has the same numerical stability as that of the QRD algorithm.
QR decomposition LS algorithm (QRD) is a widely used algorithm for adaptive arrays recently,which has good numerical stability and can be easily mapped to Systolic structure for parallel processing.However,for full adaptive array where optimal weights are needed,this method typically requries three Systolic modulars to produce optimal weight.This paper presents a new method to solve the nulling problem of a full adaptive array using inverse QR decomposition LS algorithm (IQRD) and its Systolic implementation.It can easily obtain optimal weight vector using only one Systolic array.Since it still directly deals with the input data matrix and is based on unitary transformation,the IQRD algorithm has the same numerical stability as that of the QRD algorithm.
1997, 26(1): 29-34.
Abstract:
Wavelet transform,especially the multiresolution representation is a very effective tool for analyzing the information contents of a signal.Based on Mallat's multiresolution analysis,this paper discuses the theoretical analysis of M-channel multiresolution signal decomposition,proposes a new algorithm for realizing the theory,studies the properties of an operator which approximates a signal at a given resolution,and describes experimental results.The results shows that the signals can be decomposed and reconstructed by M-channel multiresolution representation.The algorithm is proved to be simple,reliable and very useful for signal processing.
Wavelet transform,especially the multiresolution representation is a very effective tool for analyzing the information contents of a signal.Based on Mallat's multiresolution analysis,this paper discuses the theoretical analysis of M-channel multiresolution signal decomposition,proposes a new algorithm for realizing the theory,studies the properties of an operator which approximates a signal at a given resolution,and describes experimental results.The results shows that the signals can be decomposed and reconstructed by M-channel multiresolution representation.The algorithm is proved to be simple,reliable and very useful for signal processing.
1997, 26(1): 35-39.
Abstract:
A new oscillator structure for Gunn chip mounting in integ rated finline is suggested and analyzed with the conservation of complex power technique in this paper. An optimum size of the mounting structure is searched for the best match between the Gunn chip and circuit. Beacuse the structure suggested in this paper is very easy to mount Gunn chip and to tune its resonating freguency, this oscillator has high reliability and wide bandwidth with flat output power. Using this method, a Ka band integrated finiline Gunn oscillator is made with bandwidth of over 12 GHz and mo re than 30 mW out-put power.
A new oscillator structure for Gunn chip mounting in integ rated finline is suggested and analyzed with the conservation of complex power technique in this paper. An optimum size of the mounting structure is searched for the best match between the Gunn chip and circuit. Beacuse the structure suggested in this paper is very easy to mount Gunn chip and to tune its resonating freguency, this oscillator has high reliability and wide bandwidth with flat output power. Using this method, a Ka band integrated finiline Gunn oscillator is made with bandwidth of over 12 GHz and mo re than 30 mW out-put power.
1997, 26(1): 40-43.
Abstract:
An effcient algorithm to compute the equivalent circuit model parameters of SAW filter is proposed.This method is based on the charge distribution in the interdigital transducer calculated by the Remez optimazation design and takes into account the interaction of acoustic wave and electrostatic field within the IDTs.The parameters are only depended on the charge distribution,weighted coefficients and IDT overlap pattern.The simulations prove that this method is simple,precise,and fast,and can be used to optimize further practical specfication of SAW filter.
An effcient algorithm to compute the equivalent circuit model parameters of SAW filter is proposed.This method is based on the charge distribution in the interdigital transducer calculated by the Remez optimazation design and takes into account the interaction of acoustic wave and electrostatic field within the IDTs.The parameters are only depended on the charge distribution,weighted coefficients and IDT overlap pattern.The simulations prove that this method is simple,precise,and fast,and can be used to optimize further practical specfication of SAW filter.
1997, 26(1): 44-49.
Abstract:
The nonlinear oscillation of electron on the central axis of charged ring is studied.After setting up the motion equation,the exact solution and the period of free oscillation are achieved with elliptic integrals.The nonlinearity of oscillation are discussed and illustrated.Truncating expanded series leads to Duffing equation.The approximate expressions of solution and period are gained by Duffing oscillation and harmonic oscillation,which are compared with the exact ones.The appling significance of nonlinear oscillation solution in engineering is indicated.
The nonlinear oscillation of electron on the central axis of charged ring is studied.After setting up the motion equation,the exact solution and the period of free oscillation are achieved with elliptic integrals.The nonlinearity of oscillation are discussed and illustrated.Truncating expanded series leads to Duffing equation.The approximate expressions of solution and period are gained by Duffing oscillation and harmonic oscillation,which are compared with the exact ones.The appling significance of nonlinear oscillation solution in engineering is indicated.
1997, 26(1): 50-54.
Abstract:
This paper briefly introduces the formation and the development of mechatronics,and sums up the achievements in the author's researches and the researches of some Japanese scholars into the designing theories:designing principles of system;information flow designing principles;designing principles of establishing unified physic model.This paper also points out the future development of mechatroinics.
This paper briefly introduces the formation and the development of mechatronics,and sums up the achievements in the author's researches and the researches of some Japanese scholars into the designing theories:designing principles of system;information flow designing principles;designing principles of establishing unified physic model.This paper also points out the future development of mechatroinics.
1997, 26(1): 55-58.
Abstract:
Function composition is a basic logical operation in most CAD applications,and is adopted as an improvement to a binary decisions diagram (BDD) based application.This paper determines the time complexity of the graph-based composition algorithm proposed by Bryant to O(|G1|2|G2|),then improves the composition algorithm based on the efficient ITE operator.The new algorithm omits the reducing step for result BDD,keeps the BDD representation as a strong canonical form and therefore improves the composition effciency.
Function composition is a basic logical operation in most CAD applications,and is adopted as an improvement to a binary decisions diagram (BDD) based application.This paper determines the time complexity of the graph-based composition algorithm proposed by Bryant to O(|G1|2|G2|),then improves the composition algorithm based on the efficient ITE operator.The new algorithm omits the reducing step for result BDD,keeps the BDD representation as a strong canonical form and therefore improves the composition effciency.
1997, 26(1): 59-62.
Abstract:
During the past several years,a neural network approach for test generation problem in combinational circuits is investigated extensively.A test generation system based on combinational circuit's Hopfield neural network models is decribed in this paper.In the system,the probabilistic relaxation techniques are used to obtain the test vectors.Experimental results confirm the feasibility of this system.
During the past several years,a neural network approach for test generation problem in combinational circuits is investigated extensively.A test generation system based on combinational circuit's Hopfield neural network models is decribed in this paper.In the system,the probabilistic relaxation techniques are used to obtain the test vectors.Experimental results confirm the feasibility of this system.
1997, 26(1): 63-66.
Abstract:
Based on the mathematical principle of the programmable neural oscillator (PNPO),the principles and oscillating conditions,by which the constant pulse-width PNPO is built,are induced in this paper.A class of models and circuits of pulse-firing-type artificial neuron are presented.Those novel circuits can simulate the electrical behaviour of biological neurons,and output discrete pulse signals uniform in amplitude,constant in pulse width and programmable in firing frequency.Finally,those new PNPO's are implemented by use of operational transconductance amplifires (OTA's),and then their characteristics are measured in experiment.
Based on the mathematical principle of the programmable neural oscillator (PNPO),the principles and oscillating conditions,by which the constant pulse-width PNPO is built,are induced in this paper.A class of models and circuits of pulse-firing-type artificial neuron are presented.Those novel circuits can simulate the electrical behaviour of biological neurons,and output discrete pulse signals uniform in amplitude,constant in pulse width and programmable in firing frequency.Finally,those new PNPO's are implemented by use of operational transconductance amplifires (OTA's),and then their characteristics are measured in experiment.
1997, 26(1): 67-69.
Abstract:
Upon the basis of the law about varible structure control with constant value,the control law of variable structure proportional to the state variables is chosen and Liapunov function method is employed.By applying Liapunov theorem and the conditions of existence and destination for sliding mode,the stability and sliding mode of a bilinear system with single input are studied.The theorem about stability and sliding mode for this kind of system is achieved.
Upon the basis of the law about varible structure control with constant value,the control law of variable structure proportional to the state variables is chosen and Liapunov function method is employed.By applying Liapunov theorem and the conditions of existence and destination for sliding mode,the stability and sliding mode of a bilinear system with single input are studied.The theorem about stability and sliding mode for this kind of system is achieved.
1997, 26(1): 70-74.
Abstract:
According to the feature of real-time multi-tasks software systems and nonhomogeneous distributed that different task consume system time,taking task modular as basic testing unit,this paper presents a evaluation model of real-time multi-task software systems.Since the parameters,for example task period,task switch method and switch frequence are easy to analyse and test,the model possesses good extensibility and feasibility.This modeling method provides a new way for the reliability evaluation of real-time multi-task software.
According to the feature of real-time multi-tasks software systems and nonhomogeneous distributed that different task consume system time,taking task modular as basic testing unit,this paper presents a evaluation model of real-time multi-task software systems.Since the parameters,for example task period,task switch method and switch frequence are easy to analyse and test,the model possesses good extensibility and feasibility.This modeling method provides a new way for the reliability evaluation of real-time multi-task software.
1997, 26(1): 75-78.
Abstract:
This paper illustrates the tendency of real-time application software from pollingloop system,foreground/background system to multitasking system and also the characteristics of multitasking system is presented.This paper analyses typical performances:taskswitch timing,intermpt latency timing,which are procvided by real-time operating system.The relations between performances of real-time operating system and worst case design in multitasking applications are also studied.Finally the performances,which real-time operating system must offer for appication worst case design are put forward.
This paper illustrates the tendency of real-time application software from pollingloop system,foreground/background system to multitasking system and also the characteristics of multitasking system is presented.This paper analyses typical performances:taskswitch timing,intermpt latency timing,which are procvided by real-time operating system.The relations between performances of real-time operating system and worst case design in multitasking applications are also studied.Finally the performances,which real-time operating system must offer for appication worst case design are put forward.
1997, 26(1): 79-83.
Abstract:
ASIC design technology is an important capacity of the future electronics engineers.Except the theoretical presentations,the CAD tool applications and realistic chips measurements are also included in advance training courses of VLSI.This paper states a student-oriented package in the following aspects:1) A PC based IC-CAD tool is presented briefly;2) modifications and computation of MOS model,which is based on Pspice level 3 model is extented;3) the specific education chips,realized in INSA are stated.
ASIC design technology is an important capacity of the future electronics engineers.Except the theoretical presentations,the CAD tool applications and realistic chips measurements are also included in advance training courses of VLSI.This paper states a student-oriented package in the following aspects:1) A PC based IC-CAD tool is presented briefly;2) modifications and computation of MOS model,which is based on Pspice level 3 model is extented;3) the specific education chips,realized in INSA are stated.
1997, 26(1): 84-89.
Abstract:
This paper studies the equilibrium solution of Cournot model and the dynamic changes of the outputs of the firms concerned.It is proved that the equilibrium solution exists and is uniqe for any inital output choice of the first firm.It is also proved that the outputs of the two firms concerned strictly monotonicly decrease or increase.The results lay a good foundation for the further study of Cournot model with several firms.
This paper studies the equilibrium solution of Cournot model and the dynamic changes of the outputs of the firms concerned.It is proved that the equilibrium solution exists and is uniqe for any inital output choice of the first firm.It is also proved that the outputs of the two firms concerned strictly monotonicly decrease or increase.The results lay a good foundation for the further study of Cournot model with several firms.
1997, 26(1): 90-93.
Abstract:
Based on idea of a linear operation group applied to the solution to secon-order linear evolution equation,the linear operation group is developed by the generating operator of the equation popularized n-order matrix and it's basic characters are also proved in Banach space,which are the key to the solvability of high-order linear evolution equations.The solution to low-order linear evolution equations is the special case of the linear operation group.
Based on idea of a linear operation group applied to the solution to secon-order linear evolution equation,the linear operation group is developed by the generating operator of the equation popularized n-order matrix and it's basic characters are also proved in Banach space,which are the key to the solvability of high-order linear evolution equations.The solution to low-order linear evolution equations is the special case of the linear operation group.
1997, 26(1): 94-98.
Abstract:
In this paper,the problem of stability for the nonlinear system with-time delay is studied,Applying the inequality analytic method and the method of variation of parameters,the sufficient conditions of k-global exponential stability for the nonlinear system with time-delay are obtained.Examples are employed to illustrate the theory.
In this paper,the problem of stability for the nonlinear system with-time delay is studied,Applying the inequality analytic method and the method of variation of parameters,the sufficient conditions of k-global exponential stability for the nonlinear system with time-delay are obtained.Examples are employed to illustrate the theory.
1997, 26(1): 99-101.
Abstract:
Based on the previous documentary,when the real random variable sequence satisfies the definite condition,the complete convergence is discussed.And this condition is the order of their finite moment which is less than one,but the problem of the convergent rate can't be finished absolutely.In this paper,the convergent rates of the random variabe sequence are point out.At last,when the order of their finite moment is less than one,the result obtained by Xue Liugen is generalized to Banach space and the results are also shown in this paper.
Based on the previous documentary,when the real random variable sequence satisfies the definite condition,the complete convergence is discussed.And this condition is the order of their finite moment which is less than one,but the problem of the convergent rate can't be finished absolutely.In this paper,the convergent rates of the random variabe sequence are point out.At last,when the order of their finite moment is less than one,the result obtained by Xue Liugen is generalized to Banach space and the results are also shown in this paper.
1997, 26(1): 102-109.
Abstract:
Molecular electronics is one of the novel research fields developed rapidly in recent years and its theoretical successes will result in the production of molecular electronic devices,which can be assembled by using the LB (Langmuir-Blodgett) film techniques.In this paper,the progress of molecular electronics and LB techniques are briefly reviewed,and their perspectives are discussed.
Molecular electronics is one of the novel research fields developed rapidly in recent years and its theoretical successes will result in the production of molecular electronic devices,which can be assembled by using the LB (Langmuir-Blodgett) film techniques.In this paper,the progress of molecular electronics and LB techniques are briefly reviewed,and their perspectives are discussed.
1997, 26(1): 110-113.
Abstract:
This paper studies the automic analysis on the production line of sodium hypophosphite during plating baths of electroless nickel plating process.Using the principle of continuous flow spectrophotometry,the instrument of automic analysis on production line is developed.The regression equation between the sodium hypophosphite concentration and the logarithm of incident light's transmitivity is abtained through the standard concentration of sodium hypophosphite being determined.The standard deviaTPPtion of the instrument is less than 2% and the error comparing to the chemistic analytic method is less than 4%.The analytic time only takes 6 minutes.The instrument is suitble for the automic analysis of sodium hypophosphite on electroless nickel plating production line.
This paper studies the automic analysis on the production line of sodium hypophosphite during plating baths of electroless nickel plating process.Using the principle of continuous flow spectrophotometry,the instrument of automic analysis on production line is developed.The regression equation between the sodium hypophosphite concentration and the logarithm of incident light's transmitivity is abtained through the standard concentration of sodium hypophosphite being determined.The standard deviaTPPtion of the instrument is less than 2% and the error comparing to the chemistic analytic method is less than 4%.The analytic time only takes 6 minutes.The instrument is suitble for the automic analysis of sodium hypophosphite on electroless nickel plating production line.
