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Journal of Xidian University 2006 Vol.33
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Study of an efficient SOC test vector compression scheme
FANG Jian-ping;HAO Yue
J4   
Abstract （1649）      PDF（pc） （150KB）（967）       Save
Test volume is an important factor affecting the cost of the SOC Testing. In order to reduce the cost of SOC
Testing, the paper proposes a method for compression/decompression of test data, that is the Min_Comp. Based on the analysis
of the different sizes of the run-length coding, the method determines the grouping of test data and it can improve the
compression ratio and reduce the test cost. Furthermore, by introducing the prefix and tail flag, the decoder leads to lower
hardware overhead compared with those in the references. Experiments were performed on the ISCAS 89 bechmark circuits, and
the results show that the Min_Comp code has a better compression ratio than the Golomb code. Also, the decompression circuit
has a low area overhead and is easy to design.
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An active queue management scheme based on equivalent active flow number estimation
YUE Peng;LIU Zeng-ji;ZHANG Bing
J4   
Abstract （1633）      PDF（pc） （257KB）（924）       Save
Based on equivalent active flow number estimation, we propose a novel Active Queue Management(AQM) schemne called
Approximate Fairness Dropping(AFD), which is able to achieve approximate fairness by containing misbehaved flows’ access
queue opportunity. Unlike most of the existing AQM schemes, AFD does not drop the packets whose arriving rate is within the
maximum admitted rate threshold, so it protects the well-behaved flows against misbehaved ones. Moreover, it improves
throughput and decreases queuing delay. Our simulations demonstrate that this new technique outperforms the current typical
AQM schemes and closely approximates the "ideal" case, where full state information is needed.
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Special quick CTM method in real-time SAR imaging
ZHANG Guan-jie(1;2);ZHANG Tao(2);ZHANG Huan-yang(2); WANG Zhen-song(3);ZHANG Shou-hong(1)
J4   
Abstract （1734）      PDF（pc） （48KB）（900）       Save
A special Synchronous Dynamic Random Access Memory (SDRAM) controller quick Matrix transposition algorithm based
on Field-Programmable Gate Array(FPGA)is presented by analyzing read-and-write features of SDRAM, and this transposition
algorithm chiefly achieves a high efficient constant speed within read-and-write of matrix transposition and sequential. For
that, it not only takes full advantage of optimum matrix transposition read-and-write capability of SDRAM component, but also
observably improves the real-time imaging processing capability of the high resolution Synthetic Aperture Radar(SAR).
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A novel fast intra prediction algorithm in H.264/AVC
SONG Bin(1);ZHOU Ning-zhao(1);CHANG Yi-lin(1);LUO Zhong(2)
J4   
Abstract （1982）      PDF（pc） （173KB）（982）       Save
According to the intra prediction in H.264/AVC, a novel self-adaptive fast algorithm for intra prediction is
proposed. First, the computational complexity of intra prediction is decreased based on the spatial/temporal correlation of
the video sequence. Then, by using the quantization parameter, we adaptively change two key parameters to guarantee the
precision of the fast intra prediction method. Simulation results show that intra macroblock encoding of H.264/AVC is
obviously speeded up using the proposed technique. Furthermore, this algorithm is compatible with H.264/AVC, and can be used
in practice.
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Region-division calibration for 3-CCD scanner input
ZENG Ping;QIAO Ting-ting;GU Wei-song
J4   
Abstract （1594）      PDF（pc） （190KB）（845）       Save
With an aim to solve the color distortion of a 3-CCD scanner, a new region-division calibration method is proposed
based on a modified calibration model of polynomial regression and used for color managements. This paper deals emphatically
with the modification of the polynomial regression model, the strategy of automatic region-division calibration according to
precision requirement and the design of color target for region-division calibration. Experiments show that the new method
can increasingly improve the measurement precision, thereby offering the possibility of automatic measurement for printer
color characteristics with a scanner rather than a spectrometer.
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Dynamic shape finding technology research on cable structures
NIU Hai-jun
J4   
Abstract （1246）      PDF（pc） （149KB）（818）       Save
According to the deformation and motion requirement of the active main reflector of the telescope. In this paper,
a dynamic shape finding technology of cable segment is studied, and considering the deadweight and change of temperature, the
geometric model of the cable segment is built. A new method for approximating the catenary to the parabola is proposed.
According to the new method, the best reference points of the catenary segment are found.
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A distributed synchronous reservation multiple access control protocol for mobile Ad Hoc networks
ZHANG Yan-ling;SUN Xian-pu;LI Jian-dong
J4   
Abstract （1772）      PDF（pc） （197KB）（950）       Save
This paper proposes a new multiple access control (MAC) protocol named distributed synchronous reservation multiple
access control protocol(DSRP), in which the hidden and exposed terminal problems are solved, and the QoS(Quality of Service)
requirements for real-time traffic are ensured. The protocol is based on Time Division Multiplex Address(TMDA) and a
different type of traffic is assigned to different priority, according to which a node should compete for and reserve the
free slots in a different method. Moreover, there is a reservation acknowledgement process before the data transmitting in
each reserved slot, so that the intruded terminal problem is solved. The throughput and packets average drop probability of
this protocol are analyzed and simulated in a fully connected network, the results of which indicate that this protocol is
efficient to supporting real-time traffic and more suitable to MANETs.
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A model of the worm propagation and control based on firewall
ZHANG Yun-kai(1;2);MA Jian-feng(1);WANG Fang-wei(2);WANG Chang-guang(2)
J4   
Abstract （2090）      PDF（pc） （181KB）（868）       Save
The study of the firewall to the network worm propagation concentrates mainly in the single subnet or the small
scale enterprise network. In view of the control of the firewall to network worms under many subnets, a model of the worm
propagation and control based on firewall is proposed. By analyzing network worm propagation in a single subnet and cross
propagation between subnets, this model reduces the cross infection rate between subnets and suppresses network worm
propagation through the firewall. Uniform scanning and local scanning worm propagation are simulated by this model. Results
show that the effect of the firewall on uniform scanning worm is good; when the local scan rate is relatively high, the
effect of the firewall on local scanning worm is relatively poor, which is consistent with the real situation.
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Modeling and control of a flexible cable system
HUANG Jin;DUAN Bao-yan
J4   
Abstract （1586）      PDF（pc） （201KB）（977）       Save
According to the strong nonlinearity and lag of the cable feed system, a discrete model, consisting of a jointed
spring-damping system, is proposed. The cable stiffness, internal damping, joint friction, gravity and wind disturbance are
included in this model in order to give an accurate description of the cable, on the basis of which the mathematical
representation of a cable feed mechanism and a controller is developed, and a series of simulation is carried out with the
4th order Runge Kutta method. Results show the effectiveness of this model and controller.
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A new subspace method for the estimation of parameters of near field sources
ZHOU Yi;FENG Da-zheng;LIU Jian-qiang
J4   
Abstract （2053）      PDF（pc） （213KB）（847）       Save
A new subspace algorithm for jointly estimating the direction-of-arrival (DOA) and range of near field sources is
proposed. Based on the higher order statistics of the data received by the array, two matrix pencils are elaborately
constructed. The phases of the generalized eigenvalues of these two matrix pencils give the estimation of DOA and range,
while their amplitudes can automatically pair among parameters. Without spectral peak searching and pairing procedure, the
proposed algorithm gives closed-form solutions to the parameters. In addition, it can be applied to arbitrary additive
Gaussian noise environments since the fourth-order cumulants are exploited. Its effectiveness is verified by computer
simulation results.
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An adaptive random shape ROI coding method
ZHOU You-xi;LI Yun-song;WU Cheng-ke;SHI Ying-bo
J4   
Abstract （1938）      PDF（pc） （287KB）（953）       Save
Based on the principle of the Rate-Distortion slope ROI (Region of Interest) coding and the conventional bitplane
shift method, a new adaptive random shape ROI coding compression method for military satellite image systems is proposed,
which utilizes adaptive coding schemes for the low-frequency and the high-frequency components of the wavelet factors
respectively in terms of the size and shape of ROI. This adaptive method not only protects the information of a certain
object image but also obtains a high compression rate. Finally, experimental results show that when the compression rate is
16 or 32, the method satisfies the requirement for the military satellite remote sensing image system.
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An improved signature scheme based on the braid group
DING Yong(1;2);TIAN Hai-bo(1);WANG Yu-min(1)
J4   
Abstract （1677）      PDF（pc） （112KB）（862）       Save
A new enhanced conjugate signature scheme (ECSS) is proposed. Based on the simple conjugate signature scheme
(SCSS) and conjugate signature scheme (CSS), the enhanced conjugate signature scheme is brought forward utilizing the
randomization factor b and the interchangeaility of the group operation between the elements in the left subgroup and the
right subgroup of a braid group. Analysis shows that the new scheme solves the k-CSP vulnerability of SCSS and has a
significant reduction on operations and the communication bandwidth compared with the CSS scheme.
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Design and analysis of a spherical omnidirectional rolling robot with a stable platform
LI Tuan-jie;ZHU Chao
J4   
Abstract （1619）      PDF（pc） （166KB）（1045）       Save
A spherical omnidirectional rolling robot with a stable platform is presented, which is driven by two mutually
perpendicular servo motors placed within the spherical shell that induce the ball to roll in all directions at all times on a
flat surface. A stable platform exists inside the spherical robot to carry sensing devices or actuators, but it does not
rotate and keeps a stable stance when the spherical shell is rolling in any direction. The mechanical construction of the
spherical robot is introduced. Then the kinematic differential equations are derived from the nonholonomic constraints on its
motion using the generalized Euler angles, and a mathematical model of the robot’s motion is established. Finally, the
kinematic analysis and simulation of the spherical robot are developed using numerical examples.
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A fast super-resolution method for coherent signals
HUANG Lei;WU Shun-jun;ZHANG Lin-rang
J4   
Abstract （1544）      PDF（pc） （223KB）（882）       Save
A fast super-resolution method for coherent signals is developed. The novel signal subspace is obtained by the recursion of the spatially smoothed Lanczos algorithm, so it does not involve the eigendecomposition of the array covariance matrix as well as the backward recursion of the multistage wiener filter (MSWF), thereby indicating that the proposed method is more computationally efficient than the classical subspace based methods, such as the conventional EPSRIT method. The effectiveness of the proposed approach is verified by numerical results.
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An efficient high-dimensional image indexing method for relevance feedback
CUI Jiang-tao(1);SUN Jun-ding(1;2);ZHOU Li-hua(1)
J4   
Abstract （2038）      PDF（pc） （179KB）（1136）       Save
Many traditional indexing methods perform poorly in the high-dimensional vector space. The Vector Approximation File approach overcomes some of the difficulties of curse of dimensionality. A new k-nearest neighbor search algorithm based on VA-File for relevance feedback image retrieval is introduced in this paper. Based on the feedback, the correlations of the underlying similarity metric between two consecutive searches is exploited, and then the search result and feedbacks and used to filter the approximate vectors in the next search round. Experiments on the large real-world dataset show a remarkable reduction of vectors accessed and an improvement on the indexing performance compared with the existing search algorithm.
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Study of the optical signal detection reflected by the infrared scanning imaging systems
ZHAO Ming-jun(1;2);CHENG Hui-zhen(2);HU Yong-zhao(2);ZENG Xiao-dong(1)
J4   
Abstract （1471）      PDF（pc） （243KB）（861）       Save
In order to detect IR imaging systems working in a passive mode effectively, the retrodirective reflection of the optical systems against the incident laser is discussed and a new technique for a single frequency modulated CW laser against such targets is provided. Based on the analysis of echo signals’ characteristics, the technique for digital quadrature coherent detector by direct sampling has been used to detect such signals with a low S/N ratio and the expected results have been obtained in experiments.
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An MOM analysis for a mixture of conducting and dielectric objects
GUO Jing-li;LIU Qi-zhong;LI Jian-ying;ZHOU Bin
J4   
Abstract （2623）      PDF（pc） （194KB）（1141）       Save
A coupled volume-surfaced integral equation is presented for the calculation of electromagnetic scattering from metallic and dielectric targets. In the method of moments(MoM) solution to the integral equations, the target is discretized using triangular patches for metallic surfaces and tetrahedral cells for dielectric volume. According to the characteristics of the impedance matrix, a simple effective method is presented to improve the convergence of the iterative algorithm. Finally, numerical examples are given to illustrate the efficiency of the method.
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Blind channel estimation of SC-FDE systems by exploiting zero-padding: time domain approach
LI Jun;LIAO Gui-sheng
J4   
Abstract （1764）      PDF（pc） （216KB）（1030）       Save
A subspace based blind channel estimation approach for zero-padding single carrier frequency domain equalization (ZP-SC-FDE) systems is presented, which estimates the frequency-selective channel blindly in the time domain, based on zero-padding technology. Equivalence of the proposed method and the frequency domain estimation method proposed previously is proved. However the time domain method is simpler than the frequency domain method. Computer simulations show that the performance of proposed method is better than that of conventional oversampling methods, and it is robust to over-estimated channel order.
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Cited: Baidu(1)

Research on a domain specific language constructing method based on objects
HU Sheng-ming;LI Qing-shan;CHEN Ping
J4   
Abstract （1412）      PDF（pc） （220KB）（912）       Save
This paper aims at giving out a guideline for defining a DSL(Domain Specific Language) by presenting a language constructing method based on Objects. DSL semantics is analyzed and decomposed into Domain Specific Semantics and Domain Independent Semantics, and then objects are employed to encapsulate the former. View objects and model objects are used to define and interpret the Domain Specific Semantics, and language tools are used to generate the general features of a language. Then objects and general language features are combined and a DSL is constructed. This method makes the DSL constructing process rapid and clear, and more expandability can be achieved. DSL developers can implement the DSL interpreter by efficiently incorporating this method with language tools.
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A new method using fuzzy approximate melody matching for QBH based music retrieval
MA Zhi-xin;FU Shao-feng;ZHOU Li-hua
J4   
Abstract （1511）      PDF（pc） （171KB）（996）       Save
Query-by-humming is a much friendlier method for content based music information retrieval systems. Since an input humming query may have various errors, the system should be able to tolerate these errors. This paper represents a new melody matching method for the QBH based MIR system. The fuzzy relationship is established between the input query and the target data in the database by constructing the membership function of the fuzzy subset to judge the similarity of the delta pitches to its target. Both delta pitch and pitch duration ratio are used in melody representation. The DP matching method is taken to do the similarity measurements. Experimental results show the effectiveness of the new method, its top-10 success rate exceeding the traditional 5-level contour approximate matching method by 16%.
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A semidefinite programming multiuser detector with pretreatment
MU Xue-wen(1);LIU San-yang(1);ZHANG Ya-ling(2)
J4   
Abstract （1853）      PDF（pc） （161KB）（878）       Save
Based on the quadratic integral programming model of the multiuser detection problem, a detection strategy by the semidefinite programming method with pretreatment is presented. A pretreatment method is used to obtain an equivalent quadratic integral model with a lesser scale. Then, we give the semidefinite programming relaxation for the equivalent quadratic integral model. Coupled with the randomized method, we obtain the suboptimal solution to the multiuser detection problem. Compared with the semidefinite programming method, our method has the advantages of lower bit error rate and lesser CPU time, which simulations have proved.
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Method for dealing with the stochastic structure based on full-probability
LUO Wei-ting;CHEN Jian-jun;LIU De-ping
J4   
Abstract （1405）      PDF（pc） （201KB）（757）       Save
Based on the Weighted Residual Method, a new method for the analysis of the probability density of stochastic structural response under random loading is proposed, in which an approximate function expression of the problem can be deduced by the Weighted Residual Method, and then the probability desity of the random function can be calculated with the method for dealing with the function of a random vector, so all the information of the randomicity of structural response can be gained expediently. Finally, two examples illustrate the present method. A comparison of its results with that by the Monte-Carlo method shows that the proposed method is of high accuracy and feasibility.
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Classification of the FSK signal over a rayleigh fading channel
BAO Dan;YANG Shao-quan;CUI Yan-peng
J4   
Abstract （2035）      PDF（pc） （213KB）（919）       Save
We propose a modulation classifier for M-ary frequency-shift keying(MFSK) signals traveling over a frequency nonselective Rayleigh slow fading channel. This optimal classifier is developed for both synchronouse and asynchronous waveforms and is based on likelihood functions which are derived from the complex envelop of the received FSK signals contaminated by the additive white Gaussian noise (AWGN). Simulation experiments under the synchronous, asynchronous and frequency offset conditions are illustrated to validate the theoretical analysis.
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Thermal conductivity prediction of underfill and its affects on the flip chip temperature field
MA Xiao-song(1;2);CHEN Jian-jun(1)
J4   
Abstract （1481）      PDF（pc） （208KB）（879）       Save
According to the thermal conductivity theory and Haiying Li’s researching data, a prediction formula, which can be used to predicate the thermal conductivity of carbon fiber, silica and epoxy mixed packaging composite, is obtained. Finite element analysis is used to compare temperature differences between low and high thermal conductivity of composites. And research shows that high thermal conductivity composite can decrease the temperature difference of underfill between chip and substrate, so that it can improve the temperature distribution of the flip chip, decrease the thermal stress of underfill and increase packaging reliability.
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Fast wavelet transforms based on binary partition techniques
LI Yi-wei(1;2;3);YAN Yi-hua(2);SONG Guo-xiang(1)
J4   
Abstract （1661）      PDF（pc） （153KB）（1106）       Save
A fast wavelet transform based on binary partition technique(BFWT) is proposed to apply an “almost to be” FWT to matrices with non-dyadic sizes, which can not be done by the standard FWT. Implemented as a software package in FORTRAN 90 with various orthonormal or biorthonormal wavelet filters, this new algorithm is desirable for fast resolution of large-scale dense linear systems resulting from discretization of multi-dimensional integral equationsl. An illustrative example is provided to demonstrate the validity and applicability of the algorithm.
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The control arithmetic for the double inverted pendulum based on the fuzzy control theory
GUO Rui-qiu;HONG Xu;SU Wang-wang
J4   
Abstract （1633）      PDF（pc） （205KB）（1097）       Save
The double inverted pendulum is a multivariable, nonlinear, strong-complying system. The fuzzy control theory is introduced to study the controlling problem of the double inverted pendulum in this paper. The dimensions of input varieties of a fuzzy controller are depressed by designing a fusion function using the optimization control theory, and it can reduce the rules of fuzzy greatly. The infection of quantification factors to the effect of control is studied. The quality of the fuzzy controller is improved by adding auto turning quantification factors. Simulation and experiment prove that this fuzzy control arithmetic has the advantages of few rules, fast speed, good stability and good robustness.
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DBS imaging and GMTI in a wideband airborne mechanic scanning radar
LI Yan-ping;XING Meng-dao;BAO Zheng
J4   
Abstract （1720）      PDF（pc） （341KB）（1001）       Save
The principle for choosing the coherent processing number under mechanic scanning mode and a refined DBS imaging method incorporating the range migration correction are presented, which can effectively improve the resolution of a DBS image. Based on the characteristic that the echo of the moving target is modulated by the antenna pattern, a novel method combining the sub-aperture detecting with the sliding window detection is also proposed, thus proper location can be achieved. The processing results of real radar data prove its validity.
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An anisotropic diffusion equation based on the morphological operator
JIANG Dong-huan;FENG Xiang-chu;SONG Guo-xiang
J4   
Abstract （1695）      PDF（pc） （206KB）（981）       Save
An anisotropic diffusion equation based on the morphological operator is proposed to make up for the defeat of the generalized PM diffusion not to preserve edge details. Its diffusion coefficient is dependent not only on the gradient of the image, but also on the second derivatives estimated on the image after being applied to the morphological close-open operator. The new operator is capable of removing noise efficiently and preserving the edge locality and thin edges. Experiments show that the processed images have high fidelity and constrast and that the new operator has an advantage of removing noise in images with heavy Gaussian noise.
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The game and incentive in the medical insurance market
WEN Xiao-ni;SONG Guo-xiang
J4   
Abstract （1288）      PDF（pc） （129KB）（719）       Save
Medical insurance market is an asymmetric information market. By using the game theory and information economics to analyze the behavior of a hospital and insurance company. A principal-agent model and outside inspection are suggested to control the risk for the insurance company.
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Analysis and design of the instrument OS based on Linux
HE Fu-gui(1;2);WANG Jia-li(1)
J4   
Abstract （1512）      PDF（pc） （144KB）（866）       Save

The demand for the instrumental OS is becoming more and more urgent because of instrumental development. The paper analyzes Linux’s characteristics and shortages if it acts as an instrumental OS. In order to design this kind of OS that satisfies instrumental requirement, Linux’s kernel is modified in timer resolution, kernel preemption and priority reversion and so on. Improving the timer is realized by the analysis of the CPU structure; and a new preemptive kernel is realized by the integration of the dual-kernel with inserting preemptive points, and priority reversion is avoided by the realization of PIP. Finally, the test is done. The result shows that real-time performance is efficiently improved and the scope of use is extended, and thus it is effective for instrumental requirement.

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Adaptive backstepping output feedback control for nonlinear time-delay systems
CHEN Wei-sheng;LI Jun-min;LI Jing
J4   
Abstract （1762）      PDF（pc） （236KB）（785）       Save
A design approach to the adaptive output feedback controller is proposed for a class of parametric nonlinear time-delay systems by means of time-delay filters and the backstepping technique. The requirement for the nonlinear time-delay terms of the systems is relaxed. The global asymptotical tracking of given trajectories is achieved and the boundedness of all signals of the resulting closed-loop system is also guaranteed. Based on the method of the Lyapunov-Krasoviskii functional, the stability of the closed-loop system is proved. The feasibility of the proposed approach is illustrated by a simulation exampled.
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Improved MUSIC method for detection of currents
AN Zhi-juan(1;2);SU Hong-tao(1);BAO Zheng(1)
J4   
Abstract （1392）      PDF（pc） （181KB）（828）       Save
In this paper the conventional MUSIC method is modified to estimate the direction of arrival (DOA) of ocean currents, i.e., performing Toeplitzization on the array covariance matrix before implementing the MUSIC method. Theoretical analysis and simulation show that this process can reduce the effect of correlation between signals, and can therefore improve the performance of estimation remarkably. Finally by analyzing the measured data, it is shown that the improved method can detect the currents more effectively.
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Study of the optimal control model of the value-at-risk
JIANG Min(1);HU Qi-ying(2);MENG Zhi-qing(3)
J4   
Abstract （1447）      PDF（pc） （132KB）（875）       Save
The problems of value-at-risk is an important topic and have already been used widely in the finance market. This paper discusses a new optimal control model of the conditional value-at-risk in the finance market. We present the concept of α-CVaR under the confidence level vector α and its optimal control model (CCVaR) with continuous time, which can be dispersed approximatively to a problem of multi-stages analysis. Then, we present the concept of α-CVaR under the confidence level vector α and its optimal control model (SCVaR) with a discrete case. We prove that the optimal solution to the problem (SCVaR) can be obtained by solving an optimal recursive equation of dynamic programming. It is meaningful to solve the problem of the control model of the conditional value-at-risk.
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Prediction algorithm for fast fading channels based on the chaotic attractor
XIANG Zheng(1;2);ZHANG Tai-yi(1);SUN Jian-cheng(1)
J4   
Abstract （1489）      PDF（pc） （210KB）（845）       Save
A new algorithm for fast fading channel prediction is presented. This algorithms is based on the chaotic behavior of the mobile multipath fading channel. The phase space of these mobile multipath fading channel coefficients is reconstructed by the theory of time delays. Based on the stability and the fractal of the chaotic attractor, the coefficients are predicted in their phase space. Simulation results show that the proposed algorithm is a better candidate for long range prediction of the fading channel in the noise context. The experiment is carried out by utilizing fading channel data which span 63. 829 milliseconds. Simulation results show that the better prediction performance is acquired than the AR algorithm when the signal to noise ratio is 12dB.
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A technology of spatial power-combination for the random decentralized jammer array
ZHANG Yu-bing(1);ZHANG Hao(2);LIAO Gui-sheng(2)
J4   
Abstract （1613）      PDF（pc） （244KB）（1153）       Save
The paper demonstrates a technology of spatial -combination for the random decentralized jammer array by principle analysis, computer simulation and engineering tests. The technology is essentially an application of the active phased array radar theory. It just deploys jammer units distributed and builds up a huge thinning antenna array covering several square kilometers. As a conclusion, this technology not only guarantees the jammers’ mobility and field-viability, but also provides a new possible way to increase jamming power and battle effectiveness.
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Secure distributed generation of the product of shared secrets
WANG Hong(1);XIAO Hong(2);QIU Gang(2);FENG Deng-guo(1)
J4   
Abstract （2017）      PDF（pc） （162KB）（962）       Save
A new protocol for the task that give two secrets 0, 1 shared among 3 players, compute the product 0 1 but without any exposure about the secrets except the product is presented. It is a two-round protocol if new error occurs. The protocol uses the non-interactive distributed approach for multiplication of the shared secrets and the Welch-Berlekamp decoder for product reconstruction, which results in a more efficient protocol. To achieve provable security, the simulator protocol is given in the security proof.
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Research on the API model design and application in the fractional-N frequency synthesizer
LIU Zu-shen;WANG Ji-qin
J4   
Abstract （1404）      PDF（pc） （240KB）（930）       Save
The API techniques used in the fractional-N frequency synthesizer are introduced. The spurious modulation, residual phase error and model of phase error compansation in fractional-N frequency synthesis are analyzed in detail. The method used in the fractional-N frequency synthesizer with API techniques, key points of application and experimental results are provided.
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The method for improving the range resolution in a passive location system
ZHAO Hong-li;WU Tie-ping;BAO Zheng
J4   
Abstract （1552）      PDF（pc） （175KB）（962）       Save
In the passive location system based on the FM broadcast, signals are uncooperative and non-stationary. With the generation theory of the signals taken into account, it is pointed out that the range resolution of the modulated signals declines because of the intermission of modulating signals. The method for confirming intermission based on the derivative of the signals is presented. The method for setting the intermission to zeros is analyzed to improve the range resolution. The results of the procession of the field data validate the proposed method to improve the range resolution with low computation and easy real-time procession.
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A novel autofocus algorithm based on maximum total variation criteria for SAR image
MA Lun;LIAO Gui-sheng
J4   
Abstract （1768）      PDF（pc） （172KB）（1103）       Save
A novel autofocus algorithm for synthetic aperture radar (SAR) images is presented based on total variation. The method, which starts with a complex phase-degraded SAR image, after a phase errors model is introduced into the range-compressed phase-history domain, carries out phase errors correction by changing the focus until the total variation of the azimuth profile is maximized. Compared with the minimum entropy autofocus algorithm, this autofocus algorithm is of less computational complexity and easy to implement. The simulation and processing results of the measured data show the validity of the proposed method.
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A weighted feature reduction method for the power spectrum of radar HRRP
DU Lan;LIU Hong-wei;BAO Zheng;ZHANG Jun-ying
J4   
Abstract （1860）      PDF（pc） （216KB）（956）       Save

This paper proposes a weighted feature reduction method based on Fisher’ discriminant ratio(FDR) for a time-shift invariant feature, power spectrum, in radar automatic target recognition using the high-resolution range profile(HRRP). The proposed weighted feature reduction method uses the FDR vector of the target power spectrum to iteratively search for an optimal weight vector, and reduce feature dimensionality according to the optimal weight vector. Compared with using the raw power spectrum feature and some existing feature reduction methods based on Fisher’s linear discriminant, the proposed weighted feature reduction method can not only reduce the feature dimensionality, but also improve the recognition performance with low computation complexity. In the recognition experiments based on measured data, the proposed method is robust to different test data and achieves good recognition results.

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