DVB-C接收机中均衡的一种实现方法

针对DVB-C信号的特点,接收机中自适应均衡器采用的是分数间隔判决反馈均衡器的结构,与改进的CMA盲均衡算法和自适应算法DDLMS相结合.在仿真中,在有线多径信道条件下,此均衡器能较好地消除多径干扰,具有较好的性能,而不需要任何的训练序列和导频的存在.     

Deformation of a singularity of type E8 and Mordell‐Weil lattices in characteristic 2

In this paper, we study the Mordell‐Weil lattices of the family of elliptic surfaces which is arising from the E₈⁴ singularity, one of the ADE singularities in characteristic 2. And we construct a subfamily of the universal family of supersingular K 3 surfaces in characteristic 2 as an application (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)     

QAM接收机自动增益控制电路的设计

分析了自动增益控制的原理，并提出了一种应用于中频信号接收机的自动增益控制方案。本方案已经通过了接收系统的测试，满足设计要求。     

Some Area-Diameter Inequalities for Two-Dimensional Lattices

We obtain some inequalities concerning area and diameter of planar convex sets verifying the assumptions of Minkowski's Theorem, establishing the best possible upper bounds for the ratio A/D, (0,2], and for A/D when some lattice points are included.     

Preparation and properties of novel plastisols based on acrylic core-shell lattices

A series of core-shell lattices comprising a core portion of rubbery acrylic homo- or copolymers and a surrounding shell portion of glassy methyl methacrylate (MMA) homo- or copolymers were designed as plastisols for automotive underbody coatings. The lattices were synthesized by a semi-continuous seeded emulsion polymerization and characterized by using differential scanning calorimetry (DSC) and scanning electronic microscopy (SEM). DSC investigations demonstrated that the incorporation of a hard segment of MMA into the core portion and strongly polar monomer methyl acrylic acid (MAA) or cross-linker allyl methacrylate (ALMA) into the shell portion resulted in an improvement of the glass transition temperatures. SEM micrographs verified that the latex particles were always spherical with regular structure throughout the polymerization stage. Novel plastisols were developed based on the abovementioned core-shell polymers with dioctyl phthalate (DOP) or tricresyl phosphate (TCP) plasticizers, whose core portions were compatible with the employed plasticizer and whose shell portions were incompatible with the plasticizer. Evaluation of the viscosity as a function of the storage time revealed that the storage stability of the plastisols could be obtained through incorporation of the strongly polar monomer MAA or the cross-linker ALMA into the shell portions. The mechanical properties of the plastigels were improved by incorporating MMA into the core portion or by incorporating MAA or ALMA into the shell portion of the lattices. A balance between the mechanical properties of plastigels and the storage stability of plastisols should be considered during selection of the monomers both for the core and shell.     

Theory of angle-resolved photoemission for in general disordered complex lattices: applications to the off-normal emission from TiNx (100)

The theory of angle resolved photoemission for in general disordered complex lattices of semi-infinite solid systems is presented. An application of this theory to the He-I off-normal photoemission spectra from TiN_0.83 (100) reveal the same kind of vacancy-like related peaks observed for powder samples in angle integrated spectra in the UPS and XPS regime.Dedicated to Professor H. Nowotny on the occasion of his 75th birthday     

Effective Medium Analysis of Random Lattices

Calculations of effective conductivities of generalized random bond lattices representing porous media are compared to approximations using effective medium theory (EMT). We use numerical simulations of flow through 2D and 3D random lattice models, which allow for variable lattice densities and a lognormal distribution of local conductivities, to compare effective conductivities to effective medium approximations. We find that the analytical expressions provide good agreement to the simulations in 2D systems, but are in significant error in 3D systems when the standard deviation of the local conductivities is large.     

Strong semimodular lattices and Frankl's conjecture

In this paper, we show that Frankl's conjecture holds for strong semimodular lattices. The result is the first step to deal with the case of upper semimodular lattices. Received May 30, 2000; accepted in final form August 14, 2000.     

时空混沌系统的主动-间隙耦合同步

提出了离散系统中的主动-间隙耦合同步方法。该方法由同步相和自治相组成,在同步相,同步方案使得混沌系统趋于同步,而在自治相,两系统间的误差将迅速放大,导致同步失去。但只要同步相足够大,最终可实现系统的完全同步。从理论上讨论了同步条件,并在数值实验上讨论了同步相与耦合强度的关系。     

适合高阶QAM信号的加权多模盲均衡算法

该文提出了一种加权多模盲均衡算法。该算法结合了多模盲均衡算法和判决引导算法的各自优势,利用由判决符号的指数幂构成的加权项调整代价函数中的模值。在均衡器系数迭代过程中,加权项不仅随着判决符号自适应地改变,还可以根据MSE估计值作更精确地调整。理论分析和仿真结果表明,与多模盲均衡算法等其它算法相比,该文提出的算法在同等条件下可以获得更快的收敛速度和更低的稳态收敛残差,更适用于高阶QAM信号。