The robust adaptive beamformer using worse-case performance optimization can be converted to the loaded sample matrix inversion (LSMI) algorithm equivalently. For the LSMI beamformer, a novel method is developed to solve the precise Lagrange multiplier, and the optimal loading level can be computed exactly. Most important, this method gives the efficient solution to finding the optimal loading level for diagonal loading. Theoretical analysis and simulation indicate that the LSMI beamformer with the optimal negative loading can give the best performance improvement, and the constraint parameter is so selected that the larger it is the closer to optimization the improvement will be.

For avoiding severe performance degradation led by the inter-cell interference (ICI) in OFDMA systems with the frequency factor 1, the distributed coordination algorithm (CO-OCS) and coordination proportional fairness algorithm (PF-OCS) based on orthogonal complement space are proposed. The CO-OCS algorithm chooses the right regular vector of the user channel as the beamforming vector and the row span as an interference space from the left regular vectors of the interference channels. A suitable user lying in the orthogonal complement space of the interference space is scheduled to be free of suffering inter-cell interference and aggravating the interference in neighboring cells. The PF-OCS algorithm takes the fairness into account in scheduling. The CO-OCS algorithm gives a higher frequency efficiency and expands the system capacity. The PF-OCS algorithm can achieve almost 50％ the cell edge performance gain at the cost of 6％ cell throughput degradation than the CO-OCS algorithm.

To increase the security distance of quantum communication, a new scheme of decoy state quantum key distribution with a modified coherent state is proposed. The probability of multi-photon pulse in weak coherent source can be decreased by canceling two photon pulses to improve the security distance. Based on the math model of the decoy state QKD, the formula for the yield and error rate of the single photon pulse with the Modified Coherent State is deduced, and substituted in GLLP to calculate the generation rate of quantum keys. Results show that the decoy state with the Modified Coherent State can increase the secure communication distance about 10％, which is very close to that of the perfect decoy state QKD.

The unsupervised feature selection is transferred into a multiobjective optimization problem, and the immune clonal selection algorithm for multi-objective optimization is applied to solve it. Firstly, the unsupervised feature selection problem is translated into multi-objective problem. Secondly, the model and the objective functions are constructed. Lastly, each feature of significance is optimized by increasing the significance of the related features and decreasing the significance of the unrelated features. Experimental results on UCI data sets show that the error recognition rate is decreased and that the effectiveness and potential of the method are validated.

This paper considers an optimization problem of sum-rate in the Gaussian frequency-selective channel. This problem can be modeled as a competitive game model with a compensation function. We find that the compensation function can also be modeled as a game among sub-channels (called sub-channel game in this paper). In an iterative fashion, the Nash equilibrium of the sub-channel game can be reached, which is the asymptotically optimal compensation term. Stackelberg equilibrium with multiple leaders is introduced to represent the equilibrium point of the competitive game model with a compensation function. At the equilibrium point, all users operate on the optimal rate region frontier. Then, an iterative multiple water-levels water filling algorithm is proposed to efficiently reach the Stackelberg equilibrium. Simulation results show that our proposed algorithm has a significant improvement on the sum-rate compared with IWFA and exhibits the quasi-to-optimal performance.

This paper proposes a new method which aims at reducing big jitter caused by adjacent interconnection line crosstalk. Based on an analytical model of the interconnection payload, the method adaptively adjusts the signal drive strength according to the payload size to maintain the stability of communication delay, so as to effectively limit signal jitter. Compared with the drive mode of the buffer, under the condition of the same W/L of the driving buffer, the relative signal jitter decreases 29.6 percents when the length, wide and space of interconnection lines are 2mm, 0.4μm, 0.4μm, respectively, thus effectively improving the maximum operating frequency of long interconnects.

A static optimization algorithm for BPEL (Business Process Execution Language) process is proposed. The approach starts from scanning and handling all of the synchronized structures based on the synchronized analytical method. After that, the data flow and control flow analysis that utilizes the program dependence graph is made. A merge-reorder algorithm is applied to decrease the quantity of sequence activities and increase the degree of concurrency in a given process. Some pratical expriements have proved the efficiency of our static optimization algorithm.

To achieve the color calibration in the multi-spectral image print output, a new calibration method for the multi-ink printer is proposed. By sampling in the multi-ink print color space, measuring the spectral reflectance of the samples and then transforming the reflectance data to a low-dimensional spectral space, a forward look-up table is established firstly. Then by sampling in the low-dimensional spectral space and using the nonlinear optimization to determine the mapping points of the samples in the printer color space, a backward look-up table is created. Meanwhile, optimization parameters are determined according to the samples, which improves the optimization accuracy and shortens the computing time. Finally a multi-linear interpolation method is carried out on the forward and backward look-up table to achieve the spectral color calibration of the multi-ink printer. Experiments show that compared with the spectral color calibration model methods, the new method increases the colorimetric and spectral precision by 40％ and 44％, respectively, in forward calibration, and 51％ and 41％ in backward calibration. The time efficiency is improved by 96％ in backward calibration.

Aiming at the great quantity of multi-polarization high resolution range profile (HRRP), the complexity of the data distribution and the recognition algorithm, the methods based on kernel methods are proposed. Firstly two kernel functions based on the multi-polarization HRRP are defined,  and then two kernel functions are used to the kernel principal component analysis (KPCA) respectively. Finally, the nearest neighbor (1NN) classifier and the support vector machine (SVM) classifier are used for classifying targets. The multi-polarized radar HRRP can be recognized as a whole in the proposed methods, so the complexity of the recognition algorithm is reduced. Experimental results based on simulated multi-polarization HRRP data show that the methods based on the proposed kernel functions can raise the correct recognition rate greatly compared with the methods of single-polarized HRRP recognition. Also, the feature dimension can be decreased and the recognition performance can be improved to some extent compared with other methods of the multi-polarization HRRP.

To improve the efficiency of web services selection, a computational model for computing the QoS attributes of composite services is first presented, which utilizes a binary tree to express the dependency relationship of tasks in composite services, and aggregates the QoS attributes of different nodes in a bottom-up fashion. As a result, the QoS computing time is reduced by avoiding unnecessary repetitive computation. Then a web services selection approach based on the QGA (Quantum Genetic Algorithm) is proposed. Two dimensional multi-qubits (quantum bits) are employed to code chromosomes with attached identifier marking multi-paths. The quantum rotation gate is introduced to accelerate individual evolution. Experimental results show that, compared with the TGA(Traditional Genetic Algorithm), the QGA can give a better solution in a shorter time.

Introducing Agent techniques into the process of command and control system integration will solve the problem of flexible dynamic system integration. In a multi-agent system, it is necessary to collaborate between Agents as an agent has a limited capability, so a multi-agent intelligent collaboration model is presented. First of all, the relationship between services is configured by using the service process configuration model based on multi-agent cooperation according to the requirement of users. Agents collaborate with each other by using the intelligent collaboration model in support of the system integration framework and the control Agent is in charge of the execution of the service flow. The above process is finished without people's participation, which increases the intelligence of multi-agent collaboration and improve the flexibility of system integration. Finally, the model is applied to the Agent-based system integration tool, and the Border and Coast Defense simulation system is experimented as a test case. The successful integration of the various modules in the system verifies the high effectiveness of our model.

The clutter spectrum depends highly on the range and frame of bistatic airborne radars, which results in heterogeneous ground clutter and inaccurate estimation of the clutter covariance matrix in space-time adaptive processing (STAP). A new method for the compensation of the clutter spectrum is proposed. The method first gives a transform matrix by fitting the spatial steering vector of the range gate under test to that of the secondary range gate. The transform matrix is then applied to spatial data at a given Doppler gate to compensate the clutter spectrum, thus achieving an identical clutter spectrum. The conventional STAP could exploit the compensated data for the clutter suppression. Simulation results show a good improvement in processor performance.

Partner choice is a basic problem in a coded cooperative network. In this paper, a novel partner choice algorithm (Rate Adaptation Cooperation-Dynamic Protocol for Lifetime Maximization——RAC-DPLM) is proposed, which can adapt to the transmission rate and maximize network lifetime efficiently. By considering the expected traffic transmission rate, channel state information (CSI) and residual energy information (REI) together, our scheme aims at optimizing the network lifetime. Furthermore, the complexity of our scheme is reduced by converting the nonlinear program into a linear program. Our scheme is able to allocate the network resource dynamically and guarantee the QoS for different traffic rates, which contributes to the extension of the network lifetime. Simulation results show that the network lifetime is prolonged about 4～6 times compared with the fixed priority selection scheme under QoS constrains.

We propose a novel class of M-ary spread spectrum based on the quasi-Orthogonal multi-PN code. A hybrid matrix based on the Golay complementary sequence is deduced and used for the M-ary spread spectrum, which greatly enhances the band efficiency and robustness, and compared with the spread spectrum technique, it provides a larger spread gain and a stonger anti-intercept capture capability. In order to overcome the difficulties incurred by a long PN code spread spectrum system such as high computational complexity of synchronization and complicated hardware realization, a novel fast acquisition algorithm based on the 2-stage FFT is presented whose complexity is largely reduced compared with the conventional PMF-FFT algorithm. The receiver can effectively eliminate distortion caused by phase offset of the carrier using quadrature subchannel information for intersect data dispreading.

A new array optimization algorithm for the MIMO radar is proposed. First, a minimum number of physical sensors are used to get as many virtual sensors as possible, so the physical sensors efficiency is maximum; and then the virtual array of the MIMO radar is subject to a minimum redundancy array, so the resolution of the MIMO radar system is improved and the high side-lobe levels are reduced. Theoretical analysis indicates that the array of the MIMO radar optimized by the algorithm in this paper is an NLA with its elements both for receivers and for transmitters. With the same number of physical sensors, the MIMO radar in this paper can improve the ratio of mainlobe to sidelobe of the beampattern compared with other MIMO radar array geometries. Some numerical examples are simulated to verify the effectiveness of the algorithm.

This paper presents a new design technique for the triplexer based on characteristic polynomial synthesis. According to the specifications of each filter, characteristic polynomials of each filter are computed. The characteristic polynomials of the triplexer is then deduced and computed. These polynomials include information on the mutual effects between filters. Roots of the reflective characteristic polynomial are rearranged to maintain the equal ripple characteristic of the triplexer. By making use of these roots, it is easy to get the characteristic polynomials of filters. Finally, the classic synthesis method is used to get the coupling coefficients and the external Q value of each filter. To validate the theory, results computed are modeled into MWO software. Simulation results agree well with the specifications.

The language MSVL is an interval temporal logic programming language. It can be used for the purpose of modeling, simulation and verification of programs. To prove the correctness of interval temporal logic programs, we present a proof system for MSVL. To do so, a set of state axioms and state inference rules is given to deduce a program into its normal form. In addition, a set of axioms and inference rules over intervals is formalized to transform a program from one state to another. Finally, an example is given to illustrate how the axiom system works.

Based on a 17-round differential-nonlinear distinguisher of the SHACAL-2 encryption algorithm, a novel attack on 33-round SHACAL-2 is proposed by guessed subkey space division and Fast Fourier Transform (FFT). Moreover, it is shown that differential nonlinear attack on 33-round SHACAL-2 requires a data complexity of about 2⁴⁴ chosen plaintexts, and a computational complexity of about 2^496.6 33-round SHACAL-2 encryptions and about 2⁵⁰² arithmetic operations. The success rate of this attack is about 0.99. Compared with previous results, this new attack effectively improves the numbers of attacked rounds of SHACAL-2 in a single key attack scenario.

Forward-secure blind signature schemes can provide important security guarantees: all secret keys and digital signatures before current key exposure will still be secure. We make a Security analysis of the recent two new forward-secure blind signature schemes respectively proposed by Hui-Feng Huang et al and Yali Liu et al. These schemes are totally broken by cryptanalysis on the key structure or hardness problem. It is proved that they are not forward-secure.

The method of the synthetical basis function (SBFS) is introduced to analyze the scattering problem of the large array antennas. Based on the solution of the electromagnetic problems, the method accomplishes regional partition of the geometrical and physical structure of the model and brings in an equivalent current source to take the coupling between elements into consideration, thus obtaining the space of the SBFS. Compared with the conventional partition of the matrix, the method proposed in this paper can further release the heavy burden on the CPU in terms of memory and time. Therefore, this method can effectively analyze the scattering problem of large array antennas on PCs. Practical examples are analyzed using both this novel method and the conventional MoM. The comparison shows that the error of RCS is less than 2dB, which demonstrates the accuracy and efficiency of the SBFS.

Based on the theory of regions, an optimal liveness-enforcing Petri net supervisory can be obtained. However, the set of reachable states is required, which usually leads to the state explosion problem. This paper presents a symbolic approach to the computation of marking/transition separation instances for safe Petri nets by using BDD (Binary Decision Diagrams). In this paper, the structure and behavior of a Petri net are symbolically modeled by using Boolean algebra. Boolean algebra operations are implemented by BDD which are capable of representing large sets of reachable states with small shared data structures and enable the efficient manipulation of those sets. Therefore, the cost of computation and memory usage can be efficiently reduced. Finally, using the model of the well-known dining philosophers problem, we verify the efficiency of calculating the set of legal states, dangerous states, bad states and the marking/transition separation instances through different-sized problems.

A new sensor structure based on the non-contact way to detect flammable and explosive substances is presented. The working principle of the designed sensor is to measure the change in capacitance between electrodes pair under different conditions to calculate electrical permittivity of measured material. The structure, geometry and size of the ECT sensor are discussed. The sensor performances are analysed and compared. COMSOL simulation software is used to evaluate the performance of two types of designed sensor. An impedance analyzer is used to measure the capacitance between each electrode pair. Through the analysis of the result, the resolution and sensitivity of the designed ECT sensor are better than those of Planar capacitance sensors, which provides an experimental foundation for the future research work,image reconstruction of the liquid in a sealed container.

Nonlinear dimensionality reduction programs keep the local properties but relax the distances between points which are not in a neighborhood. As a new learning framework, the diffusion method realizes dimensionality reduction in a diffusion processing. Based on the theory of diffusion maps, this paper discusses the numerical method for spectral decomposition and presents the diffusion maps algorithm(DMA). Experimental results show that the DMA technique can detect the intrinsic dimensionality in high-dimensional data and is more stable in noise case.

An SVM ensemble learning algorithm based on grouped features is proposed for heterogeneous data. The feature is grouped and trained with different SVM classifiers, and then the final predict labels are obtained by the voting method. The diversity component classifiers with higher classification performance are obtained. Experimental results show that, compared with traditional ensemble learning, this method has the best performance.

In order to improve the memory bandwidth for masters accessing external memory in the SoC system, a multi-port memory controller IP core based on the AHB bus is developed. Also, an arbitration strategy for the early arbitration and request waiting priority is proposed. A number of masters in this IP core are requested to access the external memory through a number of ports. The arbitration selects the highest-priority port in the early arbitration moment and sets the request waiting time for the other ports that are not allowed the access request . The early arbitration moment occurs before the completion for the current read/write operations. When the next early arbitration moment happens, the arbitration arbitrates these timeout ports in preference. The results of simulation and hardware verification indicate that the maximum memory bandwidth is about 532MB/s and that the maximum bus utilization rate is about 90％.

The technique of sequentially rotating the feed position is introduced to increase the axial-ratio bandwidth of a circular polarized antenna array fed with a coplanar waveguide. The axial-ratio bandwidth can be increased by choosing the rotating angle of the antenna properly and compensating a corresponding phase to the feed line. Calculated results show that the axial-ratio bandwidth of the improved array is increased to 3.7％, while the axial-ratio bandwidth of the conventional array is only 0.9％. Meanwhile, the impedance bandwidth of the improved array is increased to 6.9％, compared with the conventional array whose impedance bandwidth is only 3.2％.

To solve the problem of resource efficiency in a wireless network, on the premise that the Quality of Service parameters such as packet loss rate and time delay are guaranteed, the constrained relations among packet loss rate, time delay, packet length, availability and buffer capacity are established. The network multiplexing efficiency determined by packet overhead, adaptation overhead, error correction efficiency and framing efficiency is given. With the error control mechanism, the computing method and procedures of the optimal packet length which makes the best resource efficiency of the wireless network are presented. Simulation results show that the optimal packet length of the wireless network decreases rapidly with the rise of packet loss rate, and that the network resource efficiency decreases as well. This computing method can be used in the flexible network with variable packet lengths for different services.

In order to solve the problem of various input video sources displaying in flat panel display devices which have the fixed resolution without any distortion, an algorithm for image scaling based on mixed interpolation by bilinear and bicubic is proposed, and its corresponding hardware implementation is also presented. The image scaling IP core is designed by VLSI based on the mixed interpolation. The input video sources with various formats are supported by it, and the high-precision scaling function without external storage is implemented. As an embedded IP core, the image scaling core is verified to be correct in function in the digital video processing chip DTV100B. The mixed interpolation method is superior in image detail and definition preserving to bilinear interpolation, and its expense of internal memory resources is less than half that of bicubic interpolation.

An approach to the construction of the tag location system based on the Ultra-Wideband signal is presented. The proposed scheme does not require strict synchronization among the base stations since it introduces an independent counter to record the time differences of arrival (TDOA). The proposed scheme can avoid the error caused by the asynchronous reference time and improve the location accuracy. Error analysis and simulation results are given. The simulation results show that in the proposed IEEE 802.15.4a channel the system succeeds in achieving a higher position accuracy than the traditional TDOA scheme with a reference time error. Therefore, the proposed scheme can be considered as a competitive candidate for low cost, low power consumption and low complexity indoor UWB location application scenarios.

The cyclostationarity property of the OFDM signal embedded pilots is examined based on the theory of cyclostationarity. The final conclusion of this paper can be used as the basis of the cyclostationarity-based blind algorithms. Mathematical deduction and simulation results both show that if the received signal embedded pilots are sampled at the data rate, a cyclostationary sequence can be obtained. And the cyclic period of the sequence equals the length of the OFDM symbol.

This paper proposes a multiple watermarking algorithm, which can enhance watermark security by utilizing the abundance and complexity of the nature of cellular automata and cellular automata transforms. The image is divided into non-overlapped blocks. A chaotic sequence number list decides which watermark will be embedded into a block. We encrypt the watermark and perform 2-D cellular automata transform on block with the private key, and embed the encrypted watermark into the low frequency coefficients of the block. Experimental results indicate that the proposed method is secure, robust and invisible, and that the embedding and extracting of watermarks do not interfere with each other.

In a block diagonal (BD) algorithm based multi-user MIMO downlink transmission system, a dramatic capacity loss is introduced when there is a strong correlation among row vectors of the different users' channel matrix. Specifically, two parameters for measuring the correlation are investigated. For the purpose of recovering the capacity loss, a joint transceiver design is proposed, where based on the BD algorithm at the transmitter side, a decorrelation postprocessing (DP) algorithm is invoked on the receiver side. Then computer simulation results show that the proposed joint transceiver design can efficiently improve the system capacity in the case of correlated channels.

An adaptive utility function based on the sigmoid function is proposed, which is related to the signal-to-interference plus noise (SINR) threshold and the obtained SINR, so that it will help to implement the opportunistic spectrum access by adaptively adjusting the SINR threshold, and it will satisfy the QoS requirement of multiple secondary users (SUs) fast. Meanwhile, considering the fairness among SUs, we rebuilt the pricing function to improve the Pareto optimality of the Nash equilibrium solution (NES). Based on all this, a power control model is investigated from the perspective of the non-cooperative game theory. The model is proved to be the super-modular game, and it can guarantee the existence and uniqueness of the NES. Simulation results show that the proposed power control algorithm can lead to converfence after 10 iterations, and that compared to the referenced algorithm it can save 10％ power consumption and achieve mostly 15％ improvement on the final utility.

We introduce a multiuser MIMO (MU-MIMO) downlink transmission strategy to solve the transmission problem for MIMO broadcast channels without available channel state information (CSI). By use of the scheme, base station (BS) selects a set of mobile stations (MS) and communicate simultaneously. Each transmit antenna at BS corresponds to an MS in the active user subset. The MS applies independent component analysis (ICA) algorithm to demix different components from the received mixing signals and identifies its own. Simulation results show that by applying the proposed strategy, MU-MIMO downlink transmission can be implemented successfully without CSI.

For the problem of solving the Capon beamforming algorithm under the steering vector uncertainty set, a novel method is proposed. By analyzing the characteristic of the robust optimization problem and its solving process deeply, the new solution is given, and the selection of the uncertainty constraint parameter becomes simpler, moreover, the improvement performance of the beamforming algorithm can reach the optimum. And the conclusion is drawn that the negative loading can obtain the optimal improvement performance, and the larger the selected constraint parameter, the closer to the optimum the performance of the beamforming algorithm will be. Furthermore, the zero solution can be effectively avoided by the rational selection of the constraint parameter. The final simulation attests its correctness and effectiveness.

Due to the defects of large operation and instability convergence performance in the array signal adaptive canceller under the interference, the paper proposes an enhanced array signal cascaded canceller, which has the advantages of fast convergence, smaller amount of operation and good performance with non-stationary samples. Simulation results indicate that the algorithm can reach the  same convergent performance by using half samples as the sample matrix inversion (SMI) algorithm.

In the actual airborne multi-channel GMTI system, the mismatch error exists in different channels and degrades the capability of repression for the ground clutter, thus affecting the detection of weak moving targets. To deal with this problem,  a novel channel equalization approach based on the ground clutter data is presented. In this method, according to the characteristic of the ground clutter for multi-channel radar, the wiener filter technique is applied to evaluate and compensate the mismatch errors, without refitting the radar equipments in use. Then the relationship between the performance and the correlation coefficient of the ground clutter signal is analyzed in the situation of limited samples. Finally, the effectiveness of the method proposed is validated by measured data.

A new recursive algorithm is proposed for jointly estimating the time-varying number of targets and their states through passive radar measurements. Firstly, multi-sensor central fusion scheme is adopted to improve the weak observability for passive systems. Secondly, the least square method is embedded to calculate pseudo-location measurements by which the nonlinearity is solved. Thirdly, for the scenario of the time-varying target number, the new approach involves modeling the collections of targets and measurements as random finite sets (RFSs), respectively, and applying the Gaussian mixture probability hypothesis density (GMPHD) recursion to propagate the posterior intensity, which is a first-order statistic of the random finite sets by which both the time-varying number and states of multiple targets could be estimated properly. Furthermore, data association is accomplished by all potential targets located by the least square algorithm, which could avoid the decrease of association reliability when lines of sight (LOS) from different targets are close to each other. Simulation results in a scenario of tracking targets through multiple passive sensors show the advantages of the proposed algorithm.

A composite adaptive enhancing and denoising algorithm for SAR images is presented. The SAR images are differentiated from speckle noise via scale space correlation. Because the SAR image can be described by approximate rayleigh's distribution, the complex diffusion coupled shock filter is used to enhance the signal differentiated from SAR image, and the anisotropic diffusion equation is used to denoise the speckle in the SAR image. Finally, the SAR image is reconstructed by stationary wavelet transform. Compared with traditional speckle removal algorithms, this new algorithm has better performance in terms of edge preserving and denoising.

The existence of the differences in squint angle and velocity between transmitter and receiver in the bistatic synthetic aperture radar(SAR) makes the imaging results distorted. This paper concerns the issue of bistatic SAR image geometric correction. According to the geometry of the bistatic SAR, the slant range history is particularly analyzed. In addition, the equivalent phase center (EPC) method is used to transform the bistatic model to a monostatic equivalent. Then, the expression of the geometric distortion correction for the bistatic SAR image is derived based on the  RD imaging algorithm. Finally, the validity of the method is demonstrated by simulation.