基于累积量的二维DOA估计的特征向量算法

本文提出一种基于累积量的二维ＤＯＡ估计特征向量算法,算法能同时确定目标的仰角与方位角;空间平滑累量使算法能更有效抑制高斯空间有色噪声。本文证明了,通过对累积选择,算法还可抑制非高斯空间白噪声,仿真实验证明了该算法明显估于ＭＵＳＩＣ算法。     

修正MUSIC算法对相关信号源的DOA估计性能

本文介绍了用修正ＭＵＳＩＣ算法提高相关信号源ＤＯＡ估计性能的方法。理论分析表明,采用该方法后,可将相关信号源的相关系数平均降低为原来的６３％,因而可改善ＭＵＳＩＣ算法对相关信号源的ＤＯＡ估计性能。且该方法不影响对非相关信号源ＤＯＡ的估计,计算量也无明显增加。计算机仿真实验结果验证了上述理论分析的正确性。     

高分辨率测向的改进MUSIC算法

当阵列馈电网络中存在误差时，传统ＭＵＳＩＣ算法并不总能提供高精度的辐射源出现方向。本文给出改进ＭＵＳＩＣ算法，通过在每个天线端乘以噪声，可准确地计算出ＤＯＳＡ。基于该算法的性能并不取决于阵列馈电网的误差。     

欧美的数字声音广播（DAB）技术

本文介绍和比较了欧洲Ｅｕｒｅｋａ－１４７和美国ＵＳＡＤＲ两种数字声音广播体制，讨论了信源编码算法ＭＵＳＩＣＡＭ，以及编码正交频分复用（ＣＯＦＤＭ）和带内同频（ＩＢＯＣ）传输技术。     

一种基于模糊的MUSIC改进算法

本文将模糊控制理论应用于高分辨谱估计测向中，提出ＭＵＳＩＣ算法的改进算法，我们称为Ｆｕｚｚａｙ－ＭＵＳＩＣ算法，以解决短数据，低信噪比下谱估计测向问题，并给出了在ＴＭＳ３２０Ｃ３０仿真开发系统上计算机的模拟结果。     

移动卫星通信系统中干扰抵消技术的研究

本文在对传统的并行干扰抵消ＰＩＣ算法和逐次干扰抵消ＳＩＣ算法进行了深入研究的基础上，提出了基于分组干扰抵消的ＭＩＣ算法和ＳＭＩＣ算法。其中ＳＭＩＣ算法具有计算量不大、计算时延小、硬件比较容易实现等优点。仿真结果表明，在相同传输环境下，采用ＳＭＩＣ算法的系统的误码率远低于ＳＩＣ和ＰＩＣ算法。当分组数较大时，采用ＭＩＣ算法的系统的误比特率优于ＳＭＩＣ算法，但其计算量较大。     

基于高阶循环平稳特性的二维波达方向估计算法

本文提出了一种利用虚拟双线性平行阵的循环累量域二维波达方向 （ＤＯＡ）估计算法。该算法构造了一个虚拟ＤＯＡ循环矩阵（ＶＤＯＡ Ｃｙｃｌｉｃ　Ｍａｔｒｉｘ）,井基于此矩阵进行ＤＯＡ估计。理论分析表明,通过对虚拟ＤＯＡ循环矩阵的特征值分解,就可以得到源信号的二维ＤＯＡ估计。同时由于循环累量对高斯噪声的自然盲性和对信号的选择性,该算法具有循环域和累量域ＤＯＡ估计算法的良好性能。该算法的另一特点是可以提供虚拟扩展孔径,提高了ＤＯＡ估计的性能．     

高分辨率宽带相干信号波达方向的高效估计

本文给出了一种用于多源宽带相干信号波达方向（ＤＯＡ）估计的快速算法。它是基于信号子空间技术，通过截取中心窄带频段数据并进行空间平滑来获得支方向的高效估计。文中最后通过计算机仿真，与ＣＳＭ方法进行了比较，验证了本算法的快速，高分辨率等优良性能。     

HICOM程控交换机软件AMOCOSSU分析

较详细分析了ＨＩＣＯＭ系统ＡＭＯＣＯＳＳＵ的服务范围、命令格式、各参数意义，和ＡＭＯＣＯＳＳＵ的使用举例，并给出了各命令的错误信息和建议。     

宽带相干源波达方向估计的新方法

相干信号子空间处理方法（ＣＳＭ）是一种通过构造聚焦（ｆｏｃｕｓｉｎｇ）矩阵来估计宽带相干源波达方向（ＤＯＡ）的有效方法。本文基于一致聚焦的概念，给出了一种可用于任意阵列的完全聚焦方法，从而极大地改善了ＤＯＡ的估计分辨率、估计精度等性能，大大降低了估计方法的信噪比阈值。文中在最后通过计算机仿真，与ＣＳＭ方法进行了比较，验证了本方法的优良性能。     

A test sequence selection method for protocol testing

A method for automated selection of test sequences from a protocol specification given in Estelle for the purpose of testing both control and data flow aspects of a protocol implementation is discussed. First, a flowgraph modeling the flow of both control and data expressed in the given specification is constructed. In the flowgraph, definitions and uses of each context variable, as well as each input and output interaction parameter employed in the specification, are identified. Based on this information, associations between each output and those inputs that influence the output are established. Test sequences are selected to cover each such association at least once. The resulting test sequences are shown to provide the capability of checking whether a protocol implementation under test establishes the desired flow of both control and data expressed in the protocol specification. The proposed method is illustrated by using the class 0 transport protocol as an example     

基于双光反馈垂直腔面发射激光器获取双路高速物理随机数研究

提出基于双光反馈下垂直腔面发射激光器(VCSELs) 输出的正交偏振分量混沌振荡来同时获取两 路物理随机数(PRN)的方案,数值分析了不同反馈强度下所获取的最终比特序列的随机性能 。研究结果表明,通 过选择合适的反馈参量可使VCSELs中两个偏振分量均呈现混沌振荡;其输出的两路混沌信号 作为熵源, 经8位模数转换器(ADC)量化、比特序列按位反转、异或(XOR)运算和m bit最低有效位(m-LSBs) 截 取等后续处理后可得到最终比特序列;采用美国国家标准技术研究所(NIST)提供的NIST special publication 800-22统计测试套件对基于不同反馈强度下 所产生的 混沌信号熵源所获取的最终比特序列的性能进行测试,初步确定了获取可通过NIST speical publication 800-22统计测试的两路随机数所需的反馈强 度的范围。     

Precise analysis of bit-error probability for asynchronous multicode DS-CDMA systems

A precise bit-error probability (BEP) analysis method is derived for a multicode direct-sequence code-division multiple-access (DS-CDMA) system in an additive white Gaussian noise channel. The method is applicable to a multicode DS-CDMA system with an arbitrary number of multiple code sequences, and any selection of multiple code sequences. The precise method gives results that discriminate the effect of the selection of different multiple code sequences on the BEP, whereas Gaussian approximations (GAs) do not. Thus, the new method can be used to select the best multicode set for a given system, a task that cannot be achieved using GAs. A two-step analytical procedure enables deriving an explicit, compact form for the CF of the receiver decision statistic in a DS-CDMA system with an arbitrary number of multiple code sequences, and for any selection of multiple code sequences.     

基于改进FSM的协议一致性测试方法

介绍了一种基于FSM(finite state machine)的生成一致性测试序列的改进算法,该方法混合了UIO(unique input/output)方法和T方法,UIO方法的测试能力优于T方法,但是生成的测试序列的长度较后者要长一些。实验结果表明,本改进方法的能力与UIO方法相同,并且测试序列的长度接近于T方法。     

Bit-Error Probability of Asynchronous Multicode DS-CDMA Systems in Rayleigh Fading

A precise bit-error probability analysis method for multicode DS-CDMA systems in Rayleigh fading is derived. The proposed method applies to a multicode DS-CDMA system with an arbitrary number of multiple code sequences and any selection of multiple code sequences. The method gives accurate results for Rayleigh fading while requiring only a single numerical integration of an integrand involving the well-known Q-function. The solution discriminates the effect of the selection of different multiple code sequences on the bit-error probability, whereas Gaussian approximations do not. Numerical examples show that the differences between exact and approximate methods for a multicode DS-CDMA system operating over Rayleigh fading channels may be more significant than for a single code system in Rayleigh fading channels or for a multicode system in AWGN channels when the spreading factor is not significantly large compared to the number of multiple code sequences.     

The analysis of the performance of nanometer intellectual property blocks based on interval simulation

The problems of logic and timing analysis, arising in the design and optimization stages of complex functional VLSI units, are considered. The new method of logic and timing simulation of CMOS circuits from interval estimates, which ensure the integration of two contrary approaches to solving the problem of the performance analysis, namely, the analysis of critical paths and simulation of test sequences, is proposed. The selection of the interval approach is determined by the substantial increase in specific weights of parameter variations of nanometer elements in the timing calculations.     

数字高程模型在大型信息系统试验选址中的应用

大型信息系统试验选址是试验准备工作中的关键问题，关系到整个试验的成败。传统选址方法存在效率低、不准确等不足。本文提出了一种利用数字高程模型完成试验选址的方法。 与传统选址方法相比，该方法具有高效、可靠的优势。首先利用层次分析法建立选址准则，利用选址准则对数字高程模型进行空间分析，最后确定符合试验要求的选址。本文以一大型系统试验选址为例，验证了该方法的可行性。     

基于数据流的软件测试序列自动生成技术研究

测试用例自动生成技术是软件测试的一个重要研究领域，而如何从待测试程序中选取适当的测试序列集合是其中的一个关键问题。文章提出一种构造结构性测试序列集合的方法，此方法首先对待测试程序进行静态分析，然后根据程序的语句间关系生成程序图，最后基于数据流测试准则，根据程序图以及变量的定义和使用信息构造结构性测试序列集合。在Linux平台上使用这种方法对若干条程序进行分析处理，得到的测试序列集合可以使待测试程序得到充分测试。本文提出的方法具有比较高的测试覆盖，同时，在计算过程中避免了无用路径的生成，节省了算法空间和执行时间。     

Adaptive slice-level parallelism for H.264/AVC encoding using pre macroblock mode selection

In order to achieve high computational performance and low power consumption, many modern microprocessors are equipped with special multimedia instructions and multi-core processing capabilities. The number of cores on a single chip increases double every three years. Therefore, besides complexity reduction by smart algorithms such as fast macroblock mode selection, an effective algorithm for parallelizing H.264/AVC is also very crucial in implementing a real-time encoder on a multi-core system. This algorithm serves to uniformly distribute workloads for H.264/AVC encoding over several slower and simpler processor cores on a single chip. In this paper, we propose a new adaptive slice-size selection technique for efficient slice-level parallelism of H.264/AVC encoding on a multi-core processor using fast macroblock mode selection as a pre-processing step. For this we propose an estimation method for the computational complexity of each macroblock using pre macroblock mode selection. Simulation results, with a number of test video sequences, show that, without any noticeable degradation, the proposed fast macroblock mode selection reduces the total encoding time by about 57.30%. The proposed adaptive slice-level parallelism has good parallel performance compared to conventional fixed slice-size parallelism. The proposed method can be applied to many multi-core systems for real-time H.264 video encoding.     

融合递增词汇选择的深度学习中文输入法

输入法的核心任务是将用户输入的按键序列转化为汉字序列。应用深度学习算法的输入法在学习长距离依赖和解决数据稀疏问题方面存在优势,然而现有方法仍存在两方面问题,一是采用的拼音切分与转换分离的结构导致了误差传播,二是模型复杂难以满足输入法对实时性的需求。针对上述不足提出了一种融合了递增词汇选择算法的深度学习的输入法模型并对比了多种softmax优化方法。在人民日报数据和中文维基百科数据上进行的实验表明,该模型的转换准确率相较当前最高性能提升了15%,融合递增词汇选择算法使模型在不损失转换精度的同时速度提升了130倍。