可变大小的中西文字符输入程序的设计

从点阵图像显示的角度出发，介绍了图形模式下可变大小的中西文字符输入函数的实现方法．     

CCD光电智能垂线仪

介绍了一种CCD光电智能垂线仪，其驱动信号的产生由TCD1702C及CPLD技术实现。电路设计简单，系统的稳定性和抗干扰能力强。     

高速运动环境下GNSS接收机阵列抗干扰算法

全球卫星导航系统(global navigation satellite system, GNSS)接收机高速运动状态下,干扰信号来向快速变化将导致阵列抗干扰算法性能下降,为此提出了基于干扰加噪声协方差(interference-plus-noise covariance, INC)矩阵重构的零陷加宽算法。首先,依据采样协方差矩阵相邻特征值之比估算干扰信号数目。然后,利用空间谱估计值粗略判定干扰信号来向,并根据零陷展宽需求重新设定干扰区域空间谱估计值。最后,以干扰区域谱估计值为基础重构INC矩阵,求解阵列权矢量。仿真实验表明,相比于其他零陷加宽算法,所提算法在相同展宽下的零陷更深,阵列输出载噪比(carrier to noise ratio, C/N₀)也高出5 dBHz以上。     

子阵结构FDA阵列模糊函数建模与研究

基于模糊函数的优化是频率分集阵列FDA雷达波形设计的重要手段，针对现有文献中缺乏对子阵结构频率分集阵列模糊函数研究的问题展开分析。首先建立了窄带条件下发射简单脉冲的FDA阵列数据模型，对比了FDA阵列与相控阵的方向图特性；在此基础上，基于信号经匹配滤波器输出的时域卷积出发推导出FDA阵列在三种接收信号处理机制下的复型模糊函数；然后，对采用不同频控函数的交叉子阵FDA阵列的发射方向图特性、模糊函数特性分别展开分析，并用仿真验证了采用正弦频控函数的FDA阵列具有较好的干扰抑制性能的结论，从而为后续基于子阵FDA阵列的模糊函数设计雷达波形以实现干扰抑制的一系列研究奠定了重要基础。     

并联式恒模阵的共道信号接收算法与系统误差研究

并联式恒模阵由于利用了信号的恒模特性而且结构简单，被广泛应用于共道信号接收的研究中。但现有算法对信号波达角的信息要求较高，可能造成多个阵误收敛至同一信号，并且多为理想条件下的算法分析。针对这些问题，提出了一种基于初始假设的共道信号接收方法，并对误差条件下的系统性能进行仿真。仿真结果说明此方法无需对阵列进行校正，瞄准方向误差和阵元失效对并联式恒模阵的影响较小，而对阵元位置误差敏感性稍高。     

勾股数组的群理论

文章主要以“群”概念为工具，讨论勾股数组的规律性分布，并给出公式展示勾股效组的可数性．     

基于小波变换的图像bit纠错数据并行实现研究

针对图像传输的比特纠错去噪处理高效实现,本文提出了一种基于小波分解的比特纠错SIMD PE阵列数据并行计算方法.该方法,针对不同的小波子带,采用不同的并行计算策略;针对数据并行计算中的PE选择问题,采用PE标识预置的解决方法,即确保去噪效果,又使得数据并行操作更为规则、简洁,大幅度地提高了处理的速度.     

集成阵列叉指电极介电泳芯片仿真与实验研究

分析了介电泳芯片中粒子所受的介电泳力的影响因素,采用Comsol软件建立阵列叉指电极介电泳芯片的数学模型。通过设置边界条件,对电极的电场进行仿真并对电极的尺寸参数进行优化。为了对仿真结果进行验证,采用MEMS工艺,在ITO玻璃表面制备出叉指电极结构,并与PDMS微流通道键合之后制备出完整的介电泳芯片。采用酵母菌为实验对象,分别对交流电压以及交流电压频率对介电泳的富集效率的影响进行研究。富集效率随电极施加的电压的增大而增大;但增加到一定的程度,富集效率保持不变。改变交流信号的频率,可以改变介电泳的类型。通过调整交流信号的频率,实现了酵母菌的正负介电泳富集。酵母菌在电导率为1μS/cm的悬浮溶液中,存在两个临界频率,分别为40 k Hz、15 MHz。当交流电压的频率为2 MHz时,酵母菌细胞的富集效率最高。     

Polyphase orthogonal sequences design for opportunistic array radar via HGA

Opportunistic array radar (OAR) is a new generation radar system based on the stealth of the platform, which can improve the modern radar performance effectively. Designing the orthogonal code sets with low autocorrelation and cross-correlation is a key issue for OAR. This paper proposes a novel hybrid genetic algorithm (HGA) and designs the polyphase orthogonal code sets with low autocorrelation and cross-correlation properties, which can be used in the OAR system. The novel algorithm combines with simulated annealing (SA) and genetic algorithm (GA), adds in keeping best individuals and competition in small scope, and introduces grey correlation evaluation to evaluate fitness function. These avoid the premature convergence problem existed in GA and enhance the global searching capability. At last, the genetic results are optimized to obtain the best solution by using greedy algorithm. The simulation results show that the proposed algorithm is effective for the design of orthogonal phase signals used in OAR systems.     

Cued search algorithm with uncertain detection performance for phased array radars

A cued search algorithm with uncertain detection performance is proposed for phased array radars. Firstly, a target search model based on the information gain criterion is presented with known detection performance, and the statistical characteristic of the detection probability is calculated by using the fluctuant model of the target radar cross section （RCS）. Secondly, when the detection probability is completely unknown, its probability density function is modeled with a beta distribution, and its posterior probability distribution with the radar observation is derived based on the Bayesian theory. Finally simulation results show that the cued search algorithm with a known RCS fluctuant model can achieve the best performance, and the algorithm with the detection probability modeled as a beta distribution is better than that with a random selected detection probability because the model parameters can be updated by the radar observation to approach to the real value of the detection probability.