一种基于二维细化的自适应信号捕获算法

该文针对低信噪比(SNR)情况下信号捕获精度较低的问题提出一种基于伪码相位和载波频率的2维细化自适应捕获算法,该算法根据信号强度自适应调整频率步进值和捕获门限,首先对伪码相位和载波频率进行粗捕,在此基础上对捕获到的伪码相位方格和载波频率方格进行细化,再对伪码相位和载波频率进行细捕以提高捕获精度。该文对算法进行了理论分析和仿真验证,结果表明,该算法能提高捕获的伪码相位分辨率和载波频率分辨率,有效提高检测概率,适用于低信噪比和高精度要求下的信号快速捕获。     

新的完备高斯整数序列的构造方法

该文提出了新的偶数周期的完备高斯整数序列构造方法。以整数集上的多电平完备序列为基础,并根据其周期的奇偶性,分别利用不同的组合和映射关系构造出完备高斯整数序列,所得到的完备高斯整数序列的周期等于或者2倍于多电平完备序列的周期。利用该方法可以得到新的完备高斯整数序列,从而实现了对现有完备高斯整数序列数量的扩展。     

多系统信息整合办公系统解决方案

在设计新的办公系统的时候,大多数企业都会遇到与部分已长时间运行的定制应用系统整合的问题,如何整合多个系统的基础上设计新的办公系统,实现各系统间信息互通和共享,是本文分析的主要内容。     

电工实验教学用电安全分析与防范

本文从人、物、环境和实验室管理四个方面分析探讨了电工实验中存在的各种用电安全隐患。文中结合实例针对电工实验这一具体的实践课程提出了相应的解决措施,包括人的安全意识教育、仪器设备维修更新和实验室安全用电管理方法等。经本校电工电子实验教学示范中心的实践发现这些措施都是实用可行的。     

羌族大学生体质状况调查及其影响因素的探讨--基于阿坝师专大学生体质健康测试数据的研究

运用文献资料、数理统计等研究方法,对阿坝师专羌族大学生的体质健康测试数据进行整理与分析,结果表明羌族大学生在耐力方面仍然具有优势,但体质总体水平呈下降趋势,而且民族间体质差异越来越小。研究显示学生的锻炼习惯、饮食营养、生活方式、学习压力等是影响其体质健康水平的重要因素。通过对羌族大学生体质状况调查研究,为相关高校的体育与健康教学改革提供参考。     

浅谈室内分布系统WCDMA网络的底噪问题及处理方法

室内分布系统由于直放站、无源器件的引入,多系统合路等原因,易造成WCDMA基站底噪抬升,直接影响室内分布系统的覆盖效果、话务容量及数据业务速率.简要分析了室内分布系统底噪产生的原因,并通过案例讲解几种常见底噪抬升问题的处理,有效降低底噪,提升WCDMA网络服务质量.     

地基相控阵雷达STAP应用研究

针对现代地基雷达传统方法抑制杂波不彻底的情况,根据空时二维信号处理技术（STAP）的特点和发展趋势,提出了将空时二维信号处理技术应用于地基二维相控阵雷达中的设想。根据地基雷达运动杂波的特点,在考虑误差情况下,对运动杂波二维耦合谱进行分析和仿真;初步构想了应用STAP的地基雷达无源干扰抑制结构,并对全空时自适应处理器抑制运动杂波进行仿真分析。结果表明,空时二维信号处理抑制运动杂波可以取得很好效果。     

THE CONSTRUCTIONS OF ALMOST BINARY SEQUENCE PAIRS WITH THREE-LEVEL CORRELATION BASED ON CYCLOTOMY

In this paper,a new class of almost binary sequence pair with a single zero element is presented.The almost binary sequence pairs with three-level correlation are constructed based on cyclotomic number...     

A Convenient Organic–Inorganic Hybrid Approach Toward Highly Stable Squaraine Dyes with Reduced H‐Aggregation

A generic and effective approach for solving the aggregation effect observed with optical materials in solid state or in a solution with a poor solvent was explored by designing two types of squaraine‐containing polyhedral oligomeric silsesquoixane (POSS)‐based hybrids. It is expected that incorporation of “huge” inorganic POSS nanoparticles into optical materials via covalent bonding can effectively decrease the strong dipole–dipole and π–π stacking interactions, inhibit intermolecular charge transfer between adjacent squaraine molecules, and improve optical, thermal and chemical stability of the resultant materials. Both theoretical calculations and experimental results indicate that the molecular design strategy is rational and efficacious. The resultant organic–inorganic hybrid optical materials effectively eliminate the aggregation of organic optical chromophoric groups by hindering intermolecular charge transfer and decreasing dipole–dipole and π–π stacking interaction between the chromophores, and exhibit good optical stability, i.e., the absorption peaks of H1 and H2 display only a slight blue‐shift, even in the solid. Simultaneously, the hybrids also show significantly enhanced thermal, and chemical stabilities in comparison with the precursor organic optical materials.     

Wavy Ribbons of Carbon Nanotubes for Stretchable Conductors

Wavy ribbons of carbon nanotubes (CNTs) are embedded in elastomeric substrates to fabricate stretchable conductors that exhibit excellent performance in terms of high stretchability and small resistance change. A CNT ribbon with a thin layer of sputtered Au/Pd film is transferred onto a prestrained poly(dimethylsiloxane) (PDMS) substrate and buckled out‐of‐plane upon release of the prestrain. Embedded in PDMS, the wavy CNT ribbon is able to accommodate large stretching (up to the prestrain) with little change in resistance. For a prestrain of 100%, the resistance increases only about 4.1% when the wavy CNT ribbon is stretched to the prestrain. A simple stretchable circuit consisting of a light‐emitting diode and two wavy ribbons is demonstrated and shows constant response on significant twisting, folding, or stretching. Fabricated with a simple buckling approach, the wavy CNT‐ribbon‐based stretchable conductors (e.g., interconnects and electrodes) could play an important role in stretchable electronics, sensors, photovoltaics, and energy storage.