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1.
By using Walsh matrix,a new method of parameter identification is proposed,and then an example is given.  相似文献   

2.
NewMethodofParameterIdentificationbyUsingWalshMatrix①YAOLingshi(YanshanUniversity,Qinhuangdao066004,CHN)Abstract:ByusingWalsh...  相似文献   

3.
AMethodofStructuringParameterCurvesLuoWeimin(Xi’anInstituteofPostsandTelecommunications,Xi’an,710061,P.R.China)YeZhenglinandM...  相似文献   

4.
It is well-known that turbo equalization with the max-log-map (MLM) rather than the log-map (LM) algorithm is insensitive to signal to noise ratio (SNR) mismatch. As our first contribution, an improved MLM algorithm called scaled max-log-map (SMLM) algorithm is presented. Simulation results show that the SMLM scheme can dramatically outperform the MLM without sacrificing the robustness against SNR mismatch. Unfortunately, its performance is still inferior to that of the LM algorithm with exact SNR knowledge over the class of high-loss channels. As our second contribution, a switching turbo equalization scheme, which switches between the SMLM and LM schemes, is proposed to practically close the performance gap. It is based on a novel way to estimate the SNR from the reliability values of the extrinsic information of the SMLM algorithm.  相似文献   

5.
This paper presents a new MIMO instantaneous blind identification algorithm based on second-order temporal property and steepest-descent method. Second-order temporal structure is reformulated in a particular way, such that each column of the unknown mixing matrix satisfies a system of nonlinear multivariate homogeneous polynomial equations. The nonlinear system is solved by an improved steepest-descent method. We convert the nonlinear system into an optimal problem by constructing an optimal objective function which includes a “valley-filled” item to obtain a valid solution. Our algorithm allows estimating the mixing matrix for scenarios with 4 sources and 3 sensors, etc. Finally, simulations show its effectiveness with more accurate solutions than the algorithm with homotopy method.  相似文献   

6.
7.
The analog VLSI technology processes are reaching the matureness, nevertheless, there is a big constraint, regarding their use on complex electronic products: the test. The Design for Testability paradigm was developed to permit the test plan implementation early in the design cycle. However to succeed onto this strategy, the fault simulation should be carried out in order to evaluate appropriate test patterns, fault grade and so forth. Consequently adequate fault models must be established. Due to the lack of fault models, suitable to fault simulation on OpAmps, we propose in this work a methodology for Functional Fault Modeling-FFM, and some methods for test generation. A fault dictionary for OpAmps is built and a procedure for compact test vector construction is proposed. The results have shown that high level OpAmp requirements, as slew-rate, common mode rejection ration etc., can be checked by this approach with good compromise between the fault modeling problem, the analog nature of the circuit and the circuit complexity by itself.  相似文献   

8.
Ankudinov  A. V. 《Semiconductors》2019,53(14):1891-1899
Semiconductors - Atomic force microscopy is a unique technique for probing the mechanical properties of nanostructures. Using the bending-based test method, one can measure the Young’s...  相似文献   

9.
1 Introduction OFDMisaneffectivetransmissionschemetocombatmultipathfading[1~2 ] .Ithasbeenappliedinmanycommunicationfields,suchasDigitalAudioBroadcast (DAB ) [4] ,AsymmetricalDigitalSub scriberLoop (ADSL) [5] andIEEE 80 2 1 1 .a[6] .OneoftheprincipaldisadvantagesofOFDMisthesensi tivitytofrequencyoffset.TheCFOdestroystheor thogonalityofthesubcarriers,inducesInter CarrierInterference (ICI)anddegradesthesystem perfor mancesignificantly[7~8] . Manymethodshavebeen proposedtoestim…  相似文献   

10.
The effects of stage numbers on power dissipation of pipeline analog-to-digital converter (ADC) are studied and a novel design method aiming for power optimization is presented. In this method, a minimum comparator number algorithm (MCNA) is first introduced, and then the optimum distribution of resolutions through pipeline ADC stages is deduced by MCNA. Based on the optimum stage-resolution distribution, an optimization method is established, which examines the precise function between ADC power and stage resolutions with a parameter of power ratio (Rp). For 10-bit pipeline ADC with scaling down technology, the simulation results by using MATLAB CAD tools show that an eight-stage topology with 1-bit RSD correction achieves the power optimization indicated by the power reduction ratio.  相似文献   

11.
1 Introduction In speech communication applications ,the presence ofcoupling fromloudspeaker to the microphone often re-sults in undesired acoustic echo that seriously degradesspeech quality.Current solutions for removingthis echoare based on the real ti me identification of the acoustici mpulse response by using adaptive filtering or AdaptiveEcho Cancellation (AEC) filter techniques . Several AEC algorithms have been proposed for thisproblem. An acoustic echo canceller based upon inputort…  相似文献   

12.
A Novel Admission Control Algorithm Based on Negotiation and Price   总被引:1,自引:0,他引:1  
1 Introduction In a media server that supports Quality of Service (QoS),an admission control algorithm determines whether or not anew request can be admitted to the server such that all userswill receive their required performance[1]. In general, ad mission control algorithms can be divided into deterministic,observation based and statistical ones. Deterministic algo rithms guarantee the specific QoS requirement by reservingthe resources for the worst case requirement of each applic…  相似文献   

13.
Virtual instrument is playing the important role in automatic test system. This paper introduces a composition of a virtual instrument automatic test system and takes the VXIbus based a test software platform which is developed by CAT lab of the UESTC as an example. Then a method to model this system based on Petri net is proposed. Through this method, we can analyze the test task scheduling to prevent the deadlock or resources conflict. At last, this paper analyzes the feasibility of this method.  相似文献   

14.
A new way for generating Bessel beams at mm and sub mm-wavelengths is presented in this paper, in which diffractive optical elements (DOE’s) are designed for converting incident Gaussian beams into Bessel beams. In order to reduce the computational burden and therefore improve the design efficiency, two measures are adopted in our design. One is a body-of-revolution finite-difference time-domain (BOR-FDTD) method that uses a two-dimensional (2-D) solution space instead of a full 3-D space and thereby saves tremendous computational resources, and that is utilized to calculate the fields diffracted by the DOE’s. The other is a microgenetic algorithm (MGA) that has been proved to be more effective than the conventional GA, and that is employed for accelerative optimization. The utility of the present design tool, which combines a MGA with a BOR-FDTD method, is demonstrated by three examples. Numerical simulation results indicate that the designed DOE’s can not only flexibly generate zero- or higher- order Bessel beams when compared with axicons, but also have higher diffraction efficiencies when compared with amplitude holograms. An erratum to this article can be found at  相似文献   

15.
16.
1 IntroductionOneofthekeyproblemsinhigh speeddigitalradiocommunicationistheInter Symbol Interfer ence (ISI)causedbythemulti pathbetweenthetransmitterandthereceiver.Becauseoftherelativemovementbetweenthereceiverandthetransmitterandthecontinuouschangeoftransmissionmedia,ISIisusuallytime variant.Inthepasttwotothreedecades,abroadstudyofthetype ,structureandadaptivealgorithmofadaptiveequalizershasbeencarriedouttomitigateISI[1~ 7] .Withtheintroductionofadaptiveantennasanddiversityreceptiontec…  相似文献   

17.
Vector quantization (VQ) is an efficient technique for data compression and has been successfully used in various applications. The methods most commonly used to generate a codebook are the Linde, Buzo, Gray (LBG) algorithm, fuzzy vector quantization (FVQ) algorithm, Kekre‘s Fast Codebook Generation (KFCG) algorithm, discrete cosine transform based (DCT-based) codebook generation method, and k-principle component analysis (K-PCA) algorithm. However, if the separation boundaries in codebook generation are nonlinear, their performance can degrade fast. In this paper, we present a kernel fuzzy learning (KFL) algorithm, which takes advantages of the distance kernel trick and the gradient-based fuzzy clustering method, to create a codebook automatically. Experiments with real data show that the proposed algorithm is more efficient in its performance compared to that of the LBG, FVQ, KFCG, and DCT-based method, and to the K-PCA algorithm.  相似文献   

18.
In this paper, a new way to a selection of the secure relay nodes in hybrid MANET–DTN networks based on the cooperation between routing, trust and game theory mechanisms is introduced. The hybrid MANET–DTN enables delivering the data or messages in the situation when communication paths are disconnected or broken and also in the emergency situations. We focus on the situations when MANET routing protocol cannot establish the end-to-end connection between source and destination nodes. In this situation, it is necessary to select relay nodes, that will be able to transport data or messages between isolated islands of mobile terminals with limited connectivity to other terminals. The proposed algorithm enables to select the relay nodes, that will come into contact with other mobile nodes located in different network areas with regards to trust and game theory. The parameter trust is computed for all mobile nodes and relies on a parameter obtained during routing and data transport processes. The game theory provides a powerful tool to select one candidate from a number of possible nodes with respect to confidence and security. Moreover, we propose a new mechanism to compute and select the trusted node, that can be used for transportation of the secure data in this hostile and disconnected environment. In order to verify the functionalities of this mechanism, we implement this mechanism into the OPNET modeler simulation environment and introduce performance analysis.  相似文献   

19.
AHybridAlgorithmofBPNetworkandItsApplicationtoBlindEqualization¥LiangQilian;ZhouZheng;andLiuZemin(DepartmentofRadioEngineerin...  相似文献   

20.
《安全与电磁兼容》2008,(6):102-103
用统计方法评估了两种电源端口骚扰电压测试的参考测试方法。结果表明这两种测试方法可以相互替代。  相似文献   

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