一种结合CDD 模型和Criminisi 算法的图像修复算法

针对既含有大块缺失信息又含有划痕的图像,结合CDD 模型和Criminisi 算法的 优点,提出一种新的修复算法。算法先采用可以强化细节的自适应直方图均衡化操作来扩大图 像的动态范围,后利用形态学算子分离出待修复图像中的划痕区域与大块区域,接着用CDD 模 型对划痕进行修复,再用改进优先级的Criminisi 算法进行后续修复,最后把修复后的图像对 应于缺失区域的像素填补到待修复图像的区域中。实验结果表明,改进后的算法克服了现有算 法可能存在的偏差延续问题,使图像修复的结果更加符合人们的视觉效果。     

TSR: algorithm of image hole-filling based on three-step repairing

In order to solve the hole-filling mismatch problem in virtual view synthesis, a three-step repairing (TSR) algorithm was proposed. Firstly, the image with marked holes is decomposed by the non-subsampled shear wave transform ( NSST), which will generate high-/ low-frequency sub-images with different resolutions. Then the improved Criminisi algorithm was used to repair the texture information in the high-frequency sub-images, while the improved curvature driven diffusion (CDD) algorithm was used to repair the low-frequency sub-images with the image structure information. Finally, the repaired parts of high-frequency and low-frequency sub-images are synthesized to obtain the final image through inverse NSST. Experiments show that the peak signal-to-noise ratio (PSNR) of the TSR algorithm is improved by an average of 2 - 3 dB and 1 - 2 dB compared with the Criminisi algorithm and the nearest neighbor interpolation (NNI) algorithm, respectively.     

Cyclic delay transmission for unique word OFDM systems

In this article, we propose a cyclic delay diversity （CDD） transmission scheme for unique word （UW） OFDM system, which is denoted as CDD-UW-OFDM. In our proposed CDD-UW-OFDM system, the first transmit antenna transmits a UW-OFDM and then, for every UW-OFDM block, the i-th transmit antenna transmits a cyclically delayed version of the symbols transmitted at the first transmit antenna. With this proposed CDD-OFDM system, each antenna transmission is a UW-OFDM. Also, at the receiver under a certain condition on the cyclic delay amounts, the received signal is equivMent to that of a single transmit antenna UW-OFDM transmission with a longer multipath channel. We design the lengths of UW and cyclic delays to achieve the full multipath and spatial diversities for the CDD-UW-OFDM system when the linear MMSE receiver is used. We then present some simulation results to illustrate the claimed performance of the proposed system.     

Adaptive Multiantenna Technology

Multiantenna technology can be implemented in several modes. These modes have varying characteristics and are used in different scenarios. This paper introduces Beamforming (BF), Cyclic Delay Diversity (CDD), Spatial Diversity (SD), Spatial Multiplexing (SM), and other multiantenna technologies. It also analyzes various technical features and their application scenarios. An adaptive multiantenna switching algorithm is proposed that chooses a suitable mode for sending data according to the scenario or wireless channel conditions. This switching algorithm improves multiantenna technology and enhances the quality of wireless network communications.     

基于循环延迟分集的差分空时频编码方案

结合正交空时码的分集优势,将正交空时码应用到差分空频系统中,提出了一种基于循环延迟分集的多流差分空时频编码新方法,在差分系统中同时获得了空间和频率分集.该差分编码方法在满足信道的时间和频率选择性前提下,只需要发送很少的参考矩阵用于非相干检测.仿真结果表明,正交空时码的引入,可以有效提高整个系统的分集增益,从而在很大程度上改善整个差分MIMO-OFDM系统的误码性能.     

分布式小区中CDD的功率分配方法及性能分析

为了有效地在分布式小区中使用循环延迟分集技术,文章首先得到了分布式环境下循环延迟分集的成对差错概率的上界。以最小化成对差错概率的上界为目标,提出了一种分布式环境下循环延迟分集的次优功率分配方案。仿真结果表明,通过对移动台位置信息的利用,得到其路径损耗信息,再结合次优功率分配方案,分布式小区中循环延迟分集的系统性能得到改善。     

宿州地区HDD、CDD值的变化规律与分布特征

本文采用典型气象年法对宿州地区1986-2015年气象参数进行计算分析,得出HDD、CDD值。采用平均年法对HDD、CDD值的逐年变化规律与变化趋势及年分布特征进行了分析研究。定义了基于HDD/CDD值的冷热强度与程度的概念。结论如下:典型气象年宿州地区HDD、CDD值为2009.4℃·d和155.8℃·d。1月采暖度日数占全年采暖度日数1/4。7月制冷度日数占全年制冷度日数近1/2。HDD值在30年中呈下降趋势,冷强度极值增加,相同冷强度下的冷程度减小。CDD值呈上升趋势,热强度极值增加,相同热强度下的热程度增加。过渡月份异常天气的频次增多,冷热强度增大,16℃冷强度值为5.9℃·d与26℃热强度值为1.0℃·d。     

基于密度差分的自动聚类算法

聚类作为无监督学习技术,已在实际中得到了广泛的应用.但是对于带有噪声的数据集,一些主流算法仍然存在着噪声去除不彻底和聚类结果不准确等问题.本文提出了一种基于密度差分的自动聚类算法（CDD：Clustering based on Density Difference）,实现了对含有噪声数据集的自动分类.所提算法根据噪声数据和有用数据密度的不同,实现去噪声和数据的分类,并通过构建数据间的邻域,进一步实现了对有用数据间不同类别的划分.通过实验验证了所提算法的有效性.     

码分双工系统中的干扰抑制技术

码分双工(CDD)是近年来新提出的一种双工方式,它支持上、下行信道同时使用同一频段。但是,由于上、下行信号可能存在较大的功率差异因而会导致较严重的相互干扰。该文针对这一问题提出了一套有效的干扰抑制和消除方案。首先,文中分析了CDD系统存在的几种干扰,在此基础上提出了基站端采用分布式天线和干扰消除器处理干扰的策略,移动台间的干扰则依靠定位技术和调度算法进行抑制。最后,计算及仿真结果证明了码分双工系统的可行性。     

一种基于OV5017的无线图像采集系统的设计

介绍了一种基于OV5017图像传感器的无线图像采集系统,旨在扩展无线图像传输在低端客户的应用.详细介绍了OV5017的性能和特点,此外,还简要介绍了该图像传感器的指令编程;在无线传输模块上,选择了通用的nRF2401通信模块,工作在2.4GHz频段,1MHz的传输速率,采用其方便主控芯片编程的ShockBurstTM工作方式.除了给出部分原理图外,还给出了部分编程模块.