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2000 Vol. 22, No. 1
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2000, 22(1): 1-5.
Abstract:
This paper is focused on the research of connecting the HLS(High Level Synthesis) result to the technology of IC,To connect to deferent technology, a tactics of MLTMMT(Multi Level Technology Mapping for Multi-Target)is proposed, All key points are researched which include: (1)giying the formal descirption of the technology mapping for multi-target; (2)giving the method of MLTMMT; (3)analyzing and researching many technology libraries,presenting a lineal model of area and delay of the technology cells: (4)giving the set of the general RTL components; (5)building the VHDL simulation model in different technologies.The system has been connected To 3 kinds of IC prodaction line: and this verifies the theory and method.
This paper is focused on the research of connecting the HLS(High Level Synthesis) result to the technology of IC,To connect to deferent technology, a tactics of MLTMMT(Multi Level Technology Mapping for Multi-Target)is proposed, All key points are researched which include: (1)giying the formal descirption of the technology mapping for multi-target; (2)giving the method of MLTMMT; (3)analyzing and researching many technology libraries,presenting a lineal model of area and delay of the technology cells: (4)giving the set of the general RTL components; (5)building the VHDL simulation model in different technologies.The system has been connected To 3 kinds of IC prodaction line: and this verifies the theory and method.
2000, 22(1): 6-12.
Abstract:
A novel cluster analysis method supervised by statistical tests is proposed in this paper, which processes three key problems in data analysis, cluster tendency, cluster analysis and cluster validity, simultaneously. So, it provides an analysis tool for the validity and reasonableness of pattern unsupervised classification, especially in the case of large number of samples. The experimental results demonstrate its effectiveness.
A novel cluster analysis method supervised by statistical tests is proposed in this paper, which processes three key problems in data analysis, cluster tendency, cluster analysis and cluster validity, simultaneously. So, it provides an analysis tool for the validity and reasonableness of pattern unsupervised classification, especially in the case of large number of samples. The experimental results demonstrate its effectiveness.
2000, 22(1): 13-18.
Abstract:
Based on the analysis of the defect of the RPCL, a new competitive learning algorithm is proposed. In the new algorithm the data density is introduced, and the modification of the weights is taken into account to surmount the defect of the RPCL. It is shown by the theoretical analysis and experimental results that the new algorithm can automatically select the appropriate number of the clusters in a data set, and improve the clustering accuracy and convergence speed.
Based on the analysis of the defect of the RPCL, a new competitive learning algorithm is proposed. In the new algorithm the data density is introduced, and the modification of the weights is taken into account to surmount the defect of the RPCL. It is shown by the theoretical analysis and experimental results that the new algorithm can automatically select the appropriate number of the clusters in a data set, and improve the clustering accuracy and convergence speed.
2000, 22(1): 19-22.
Abstract:
Vector quantization plays an important role in speech recognition.Traditional K-means algorithm owns the advantage of fast convergence, but it is difficult to get the global optimal result.Some modified algorithms have been proposed to overcome this drawback,but they also increase the computation greatly.In this papsr,a new algorithm which is based on annealing algorithm is proposed to compromise the contradiction.In the rest of the paper,the details of the algorithm and related experiments are given.The results demonstrate the algorithm is more effective than other methods.
Vector quantization plays an important role in speech recognition.Traditional K-means algorithm owns the advantage of fast convergence, but it is difficult to get the global optimal result.Some modified algorithms have been proposed to overcome this drawback,but they also increase the computation greatly.In this papsr,a new algorithm which is based on annealing algorithm is proposed to compromise the contradiction.In the rest of the paper,the details of the algorithm and related experiments are given.The results demonstrate the algorithm is more effective than other methods.
2000, 22(1): 23-27.
Abstract:
In this paper,perceptual error threhhold (PET) functions in different wavelet subbands are obtained through subjective tests on artificial patterns，A new and generic two stage coding scheme is thus proposed,based on the nonuniform zero-trees of wavelet coefficients and the visually nonuniform quantization of small coefficients in higher subbands.Researches have been done for the visual transparent and nearly transparent cases,in comparisons with JPEG standard.Experimental results showed the feasibility and robustness of the scheme,Transparent quality can be obtained around 10 compression ratios for natural images.
In this paper,perceptual error threhhold (PET) functions in different wavelet subbands are obtained through subjective tests on artificial patterns，A new and generic two stage coding scheme is thus proposed,based on the nonuniform zero-trees of wavelet coefficients and the visually nonuniform quantization of small coefficients in higher subbands.Researches have been done for the visual transparent and nearly transparent cases,in comparisons with JPEG standard.Experimental results showed the feasibility and robustness of the scheme,Transparent quality can be obtained around 10 compression ratios for natural images.
2000, 22(1): 28-34.
Abstract:
In this paper, the mechanism of the performance degration due to channel mismatching and sensor coupling in azimuthms and frequencies is analyzed. A new comprehensive calibration method that can compensate error by a known sound source is proposed. The method is easy to be implemented and the results of acoustic experiments in anechoic room show that offered method is effective.
In this paper, the mechanism of the performance degration due to channel mismatching and sensor coupling in azimuthms and frequencies is analyzed. A new comprehensive calibration method that can compensate error by a known sound source is proposed. The method is easy to be implemented and the results of acoustic experiments in anechoic room show that offered method is effective.
2000, 22(1): 35-41.
Abstract:
ln this paper,the spectral correlation conjugate cyclic ESPRIT with Minimum Redundancy Linear-Arrays (MRLA) is presented.The algorithm constructs the pseudodata matrix of MRLA to estimate Direction-Of-Arrival (DOA) through temporal and spatial processing The equivalent array aperure of the algorithm is 2N-1 with M-sensor MRLA (NM).Theoretical analysis and computer simulations show that the algorithm is of better performance,such as extending aperture,being insensitive to noise,having higher resolution,and estimating more sources With fewer sensors
ln this paper,the spectral correlation conjugate cyclic ESPRIT with Minimum Redundancy Linear-Arrays (MRLA) is presented.The algorithm constructs the pseudodata matrix of MRLA to estimate Direction-Of-Arrival (DOA) through temporal and spatial processing The equivalent array aperure of the algorithm is 2N-1 with M-sensor MRLA (NM).Theoretical analysis and computer simulations show that the algorithm is of better performance,such as extending aperture,being insensitive to noise,having higher resolution,and estimating more sources With fewer sensors
2000, 22(1): 42-47.
Abstract:
Wideband beamforming with constant beamwidth is one of the key problems in array signal processing. In this paper, a method based on uniform sidelobe is given. And the frequency response needed to realize constant beamwidth for subband components of the signal is computed and filter with FIR filters. This method is suitable for uniform linear array, and is also effective when the element has its own pattern or when its location is inaccurate. Computer simulation shows the feasibility of this method.
Wideband beamforming with constant beamwidth is one of the key problems in array signal processing. In this paper, a method based on uniform sidelobe is given. And the frequency response needed to realize constant beamwidth for subband components of the signal is computed and filter with FIR filters. This method is suitable for uniform linear array, and is also effective when the element has its own pattern or when its location is inaccurate. Computer simulation shows the feasibility of this method.
2000, 22(1): 48-54.
Abstract:
This paper studies the parameterized respresentations of symmetrical interpolating scaling functions and their duals.Based on this,the optimal design method and corresponding minimax algorithm of the regularity of a novel type of interplating wavelet systems，biorthogonal interpolating wavelet system with compact supported dauls are proposed.The optimal results show that the approximation power of the system to smooth signals is markedly improved. The regularity of the duals enhances,and the magnitude responses of the dual filters are optimized.
This paper studies the parameterized respresentations of symmetrical interpolating scaling functions and their duals.Based on this,the optimal design method and corresponding minimax algorithm of the regularity of a novel type of interplating wavelet systems，biorthogonal interpolating wavelet system with compact supported dauls are proposed.The optimal results show that the approximation power of the system to smooth signals is markedly improved. The regularity of the duals enhances,and the magnitude responses of the dual filters are optimized.
2000, 22(1): 55-60.
Abstract:
This paper analyzes a kind of chaotic modulation signals,the phase-modulated radar signals are generated by chaotic signals,at the same time the ambiguity function of the coded signals is given.Theory and simulation results show that the ambiguity function of chaotic modulated signals is approximatly thumbtack-shapeas the ideal results,thus the signal has high resolution both in time-delay domain and Doppler frequency domain.It implies the possibility and advantages for chaos to be used in radar signal processing.
This paper analyzes a kind of chaotic modulation signals,the phase-modulated radar signals are generated by chaotic signals,at the same time the ambiguity function of the coded signals is given.Theory and simulation results show that the ambiguity function of chaotic modulated signals is approximatly thumbtack-shapeas the ideal results,thus the signal has high resolution both in time-delay domain and Doppler frequency domain.It implies the possibility and advantages for chaos to be used in radar signal processing.
2000, 22(1): 61-67.
Abstract:
The pass band characteristics of localized SINR polarization filter is investigated in the noncoherent, purely polarized and single signal-interference case. Specifically, formulae of the pass band of SINR filter on the great circle and circlet polarization tracks are derived. Pass band characteristics of filters are analyzed versus parameters of the electromagnetic circumstance and a group of typical pass band characteristics curves are given.
The pass band characteristics of localized SINR polarization filter is investigated in the noncoherent, purely polarized and single signal-interference case. Specifically, formulae of the pass band of SINR filter on the great circle and circlet polarization tracks are derived. Pass band characteristics of filters are analyzed versus parameters of the electromagnetic circumstance and a group of typical pass band characteristics curves are given.
2000, 22(1): 68-72.
Abstract:
An algorithm for generating k-ary de Bruijn sequences from m-ary de Bruijn sequences is given in this paper. Its each operational step produces a string of elements instead of one element. Hence the algorithm reduces the time of operation, and accelerates the speed of generation.
An algorithm for generating k-ary de Bruijn sequences from m-ary de Bruijn sequences is given in this paper. Its each operational step produces a string of elements instead of one element. Hence the algorithm reduces the time of operation, and accelerates the speed of generation.
2000, 22(1): 73-77.
Abstract:
This paper points out a mistake occurred in the Protocol(1)(W.Mao, 1995), the mistake is due to a wrong initial assumption, also this paper shows the weakness of the N-u based-rules. Finaly, an application of the N-u rules is given by an example.
This paper points out a mistake occurred in the Protocol(1)(W.Mao, 1995), the mistake is due to a wrong initial assumption, also this paper shows the weakness of the N-u based-rules. Finaly, an application of the N-u rules is given by an example.
2000, 22(1): 78-83.
Abstract:
Under the situation of unknown channel response,blind sequence estimation(BSE) recovers source symbols from received noisy data directly.As an optimal information detection approach,BSE babed on Viterbi algorithm needs searching a trellis whose state number is exponential to the observation length lt is not practical when observation length increases unceasingly.A novel BSE scheme is proposed in this paper,which uses several first estimated resultS tO recover current symbol.The computation burden is lower because it is irrelevent to observation length．The feasibility has been checked by simulation results.
Under the situation of unknown channel response,blind sequence estimation(BSE) recovers source symbols from received noisy data directly.As an optimal information detection approach,BSE babed on Viterbi algorithm needs searching a trellis whose state number is exponential to the observation length lt is not practical when observation length increases unceasingly.A novel BSE scheme is proposed in this paper,which uses several first estimated resultS tO recover current symbol.The computation burden is lower because it is irrelevent to observation length．The feasibility has been checked by simulation results.
2000, 22(1): 84-89.
Abstract:
A voting protocol is designed based on elliptic curve cryptosystems. This protocol enables each anonymous voter to vote on computer network, defends any cheat and makes secure elections possible.
A voting protocol is designed based on elliptic curve cryptosystems. This protocol enables each anonymous voter to vote on computer network, defends any cheat and makes secure elections possible.
2000, 22(1): 90-97.
Abstract:
The previous research on administration of the transmission capacity in the wired/wireless ATM networks only focuses on wired part or wireless part,There are very few people do the work extending to the links associating With handoff in the whole network.and the VPs among the base station controllers in the wired/wireless ATM networks: which adapt to the traffic state of each service in every cellular cell to allocate(provision)transmission capacity and to reserve handoff guard capacity on these links,respectively,By simnlating and analyzing the performance of the algorithm,it is found that it does well for the multlimedia communication in which the transmission capacity requirement of each service may be widely different, so that the network bandwidth resource can be used efficiently.
The previous research on administration of the transmission capacity in the wired/wireless ATM networks only focuses on wired part or wireless part,There are very few people do the work extending to the links associating With handoff in the whole network.and the VPs among the base station controllers in the wired/wireless ATM networks: which adapt to the traffic state of each service in every cellular cell to allocate(provision)transmission capacity and to reserve handoff guard capacity on these links,respectively,By simnlating and analyzing the performance of the algorithm,it is found that it does well for the multlimedia communication in which the transmission capacity requirement of each service may be widely different, so that the network bandwidth resource can be used efficiently.
2000, 22(1): 98-103.
Abstract:
In this paper, a new video coding system based on wavelet transform is presentea,and a rate centrel algorithm is preposed for it．First: 3D wavelet transform is performed to the original image sequence,and an extension of set partitioning in hierarchical trees algorithm is used to quantize the wavelet coefficients.the rate of the coder is contrelled at GOP scale.ensuring that output conforms to the parameters of a leaky bucket Controller.Several leaky buckets with different sizes are discussed too.The simulation shows the efficiency of our coding system and rate control algorithm.
In this paper, a new video coding system based on wavelet transform is presentea,and a rate centrel algorithm is preposed for it．First: 3D wavelet transform is performed to the original image sequence,and an extension of set partitioning in hierarchical trees algorithm is used to quantize the wavelet coefficients.the rate of the coder is contrelled at GOP scale.ensuring that output conforms to the parameters of a leaky bucket Controller.Several leaky buckets with different sizes are discussed too.The simulation shows the efficiency of our coding system and rate control algorithm.
2000, 22(1): 104-111.
Abstract:
In this paper,the solutions to the security issues of Internet/Intranet environment are proposed.And authentication and key distribution protocols are presented,which can be incorporated into the OSI (Open System Interconnection) architecture.The protocol adopt modified Kerberos authentication protocol at the lower sublayer, and design authenticated key exchange protocols using symmetric or asymmetric cryptosystem at the upper sublayer for different solutions.The protocols can be used for remote access applications,thus it is benefit to security manage of Intranet.
In this paper,the solutions to the security issues of Internet/Intranet environment are proposed.And authentication and key distribution protocols are presented,which can be incorporated into the OSI (Open System Interconnection) architecture.The protocol adopt modified Kerberos authentication protocol at the lower sublayer, and design authenticated key exchange protocols using symmetric or asymmetric cryptosystem at the upper sublayer for different solutions.The protocols can be used for remote access applications,thus it is benefit to security manage of Intranet.
2000, 22(1): 112-117.
Abstract:
In this paper an adaptive genetic algorithms is presented.The adaptive method of probabilities of reproduction, crossover,and mutation which have selectivity about the operated solutions is adopted in the course of calculation.It makes the reproduction probability of the solution which has the similar fitness decrease, the probabilities of crossover and mutation increase, hence it inaintains the diversity in the population and sustains the search capacity of the genetic algorithms．The method is tested by the genetic algorithm testing functions.
In this paper an adaptive genetic algorithms is presented.The adaptive method of probabilities of reproduction, crossover,and mutation which have selectivity about the operated solutions is adopted in the course of calculation.It makes the reproduction probability of the solution which has the similar fitness decrease, the probabilities of crossover and mutation increase, hence it inaintains the diversity in the population and sustains the search capacity of the genetic algorithms．The method is tested by the genetic algorithm testing functions.
2000, 22(1): 118-123.
Abstract:
This paper analyzes the possibility and presents the method for performing MTI in LFM-CW radars. Computer simulation proves that the analysis is correct and the method is practical. Results show that MTI in LFM-CW radar is very similar to that in pulse radar.
This paper analyzes the possibility and presents the method for performing MTI in LFM-CW radars. Computer simulation proves that the analysis is correct and the method is practical. Results show that MTI in LFM-CW radar is very similar to that in pulse radar.
2000, 22(1): 124-129.
Abstract:
This paper uses iteratively reweighted least square method to design pulse compression filters,which is applicable to biphase code:polyphase code,LPM and NLFM signals.As we redefine the object function and constraint condition, the performance of this method is superior to that of the conventional frequency domain weighted window method.When the Doppler frequency shift fd=0 and the coefficient of 4dB mainlobe width is kept to be 1 and the compression ratio is not high and the tap number of FIR filter is limited, the peak sidelobe level is less than -40dB.
This paper uses iteratively reweighted least square method to design pulse compression filters,which is applicable to biphase code:polyphase code,LPM and NLFM signals.As we redefine the object function and constraint condition, the performance of this method is superior to that of the conventional frequency domain weighted window method.When the Doppler frequency shift fd=0 and the coefficient of 4dB mainlobe width is kept to be 1 and the compression ratio is not high and the tap number of FIR filter is limited, the peak sidelobe level is less than -40dB.
2000, 22(1): 130-136.
Abstract:
This paper mainly studies the influence of multi-sensors positions on a long range aeroplane tracking accuracy. From theory and simulations, It is obtained that the rational positions of multi-sensors can improve the target tracking accuracy in nonlinear systems.
This paper mainly studies the influence of multi-sensors positions on a long range aeroplane tracking accuracy. From theory and simulations, It is obtained that the rational positions of multi-sensors can improve the target tracking accuracy in nonlinear systems.
2000, 22(1): 137-143.
Abstract:
In this paper a novel system of combined X-band radiometer-scatterometer is reported.This system is especially designed for correlated observation of active and passiveremote sensing. By employing this system,multi-polarized (vv, hh, vh, hv) backscattering coefficients and v, h-polarized brightness temperature can be measured simultaneously.An example of scattering and emission from land surface and metal targets is presented.
In this paper a novel system of combined X-band radiometer-scatterometer is reported.This system is especially designed for correlated observation of active and passiveremote sensing. By employing this system,multi-polarized (vv, hh, vh, hv) backscattering coefficients and v, h-polarized brightness temperature can be measured simultaneously.An example of scattering and emission from land surface and metal targets is presented.
2000, 22(1): 144-150.
Abstract:
This paper reports the light emission from MIM tunnel diode and Negative Differential Resistance (NDR) in its I-V characteristic curve. By building the trapezoid potential barrier model and calculating the numerical solution of I-V characteristic curve with computer, it is found that the increment of potential barrier average width is agree with the experiment well. This increment of potential barrier average width is caused by the SPP s impeding and trapping effect upon tunneling electrons.
This paper reports the light emission from MIM tunnel diode and Negative Differential Resistance (NDR) in its I-V characteristic curve. By building the trapezoid potential barrier model and calculating the numerical solution of I-V characteristic curve with computer, it is found that the increment of potential barrier average width is agree with the experiment well. This increment of potential barrier average width is caused by the SPP s impeding and trapping effect upon tunneling electrons.
2000, 22(1): 151-155.
Abstract:
In this paper, the application of conjugate gradient method in adaptive array beamforming is studied.The combination of temporal and spatial averaging for calculating the gradient improves the beamforming performance and releases the constfaint given by G.D.Mandyam(1997)that the number of elements must be twice larger than the number of signals.New forward and backward averaging(FB)method and multilayer FB structure are proposed which further improve the beamforming performance.Several simulation results are included for illustration and comparison.
In this paper, the application of conjugate gradient method in adaptive array beamforming is studied.The combination of temporal and spatial averaging for calculating the gradient improves the beamforming performance and releases the constfaint given by G.D.Mandyam(1997)that the number of elements must be twice larger than the number of signals.New forward and backward averaging(FB)method and multilayer FB structure are proposed which further improve the beamforming performance.Several simulation results are included for illustration and comparison.
2000, 22(1): 156-159.
Abstract:
Nonuniformly spaced 16QAM(Quadrature Amplitude Modulation) and 64QAM schemes with unequal error protection(UEP) that are designed using Trellis Coded Modulation (TCM) are proposed in this paper. Compared with conventional uniformly spaced MQAM, both the important data and the less important data of UEP MQAM can obtain several decibels of coding gain.
Nonuniformly spaced 16QAM(Quadrature Amplitude Modulation) and 64QAM schemes with unequal error protection(UEP) that are designed using Trellis Coded Modulation (TCM) are proposed in this paper. Compared with conventional uniformly spaced MQAM, both the important data and the less important data of UEP MQAM can obtain several decibels of coding gain.
2000, 22(1): 160-161.
Abstract:
It is an open problem whether a orthogonal system is characterized by its difference distribution table. The problem is solved in this paper.
It is an open problem whether a orthogonal system is characterized by its difference distribution table. The problem is solved in this paper.
2000, 22(1): 162-164.
Abstract:
Permutation polynomials play an important role in communication field. As a generalization, the concept of orthogonal system of polynomials in n indeterminates over finite field was introduced by R.Lidl and H.Niederriter(1983). In this paper, this problem is discussed and several results are obtained.
Permutation polynomials play an important role in communication field. As a generalization, the concept of orthogonal system of polynomials in n indeterminates over finite field was introduced by R.Lidl and H.Niederriter(1983). In this paper, this problem is discussed and several results are obtained.
2000, 22(1): 165-169.
Abstract:
In this paper，A multicarrier signaling technique is applied to a direct-sequence CDMA system．A data sequence multiplied by a spreading sequence modulates multipte. Carriers in transmitter，the receiver provides a correlator for each carrier, and the ouputs of the correlators are combined with a maximal-ratio combiner．This type of signaling has the desirable properties of a narrow band interference suppression effect．The system performance is evaluated in the presence of partial band interference，it is compared with that of a single-carrier DS CDMA system.
In this paper，A multicarrier signaling technique is applied to a direct-sequence CDMA system．A data sequence multiplied by a spreading sequence modulates multipte. Carriers in transmitter，the receiver provides a correlator for each carrier, and the ouputs of the correlators are combined with a maximal-ratio combiner．This type of signaling has the desirable properties of a narrow band interference suppression effect．The system performance is evaluated in the presence of partial band interference，it is compared with that of a single-carrier DS CDMA system.
2000, 22(1): 170-173.
Abstract:
The transmitting signal of Linear Frequency Modulation Continuous Wave (LFMCW) radar has two nonideal parameters: sweep nonlinearity and power undulation. They make the practical range precision and range resolution of LFMCW radar decrease. This paper analyses the effects of the power undulation on the range precision and range resolution according to the echo power spectrum of LFMCW radar, and gives theoretical bases for choosing its oscillator.
The transmitting signal of Linear Frequency Modulation Continuous Wave (LFMCW) radar has two nonideal parameters: sweep nonlinearity and power undulation. They make the practical range precision and range resolution of LFMCW radar decrease. This paper analyses the effects of the power undulation on the range precision and range resolution according to the echo power spectrum of LFMCW radar, and gives theoretical bases for choosing its oscillator.
2000, 22(1): 174-176.
Abstract:
Unequally spaced arrays are characterized by high side lobes. To reduce the side lobes, traditional genetic algorithm is modified to optimize the position of elements in the array. Due to the high flexibility of genetic algorithm, the results obtained for a 25-element array over an aperture of 50 are better than those reported in the literatures
Unequally spaced arrays are characterized by high side lobes. To reduce the side lobes, traditional genetic algorithm is modified to optimize the position of elements in the array. Due to the high flexibility of genetic algorithm, the results obtained for a 25-element array over an aperture of 50 are better than those reported in the literatures
