基于DSP和SHDSL的高速数据传输系统设计

在石油测井系统中,进行远距离数据传输时,系统传输速率太小,目前其最大传输速率也只能达到500Kbit/s,这样的传输速率已经不能满足需要。基于以上背景,本文设计了一个以DSP（TMS320VC5402）为核心CPU、使用SHDSL技术应用于工业领域的高速数据传输系统,其最大传输速率为2Mbit/s,最大传输距离可达到7.5km。     

Plate reinforced square hollow section X-joints subjected to in-plane moment

The static test of 13 square hollow section(SHS) X-joints with different β and different types of plate reinforcement under in-plane moment in brace was carried out. Experimental test schemes, failure modes of specimens, moment-vertical displacement curves, moment-deformation of the chord, and strain strength distribution curves were presented. The effect of β and plate reinforcement types on in-plane flexural property of SHS X-joints was studied. Results show that punching shear of chord face disappears, brace material fracture appears and concave and convex deformation of chord decrease when either collar plates or doubler plates were welded on chord face. Moment-vertical displacement curves of all specimens have obvious elastic, elastic-plastic and plastic stages. As β increases, the in-plane flexural ultimate capacity and initial stiffness of joints of the same plate reinforcement type increase, but ductility of joints decreases. With the same β, the in-plane flexural initial stiffness and ultimate capacity of doubler plate reinforced joints, collar plate reinforced joints, and unreinforced joints decrease progressively. Thickness of reinforcement plate has no obvious effect on in-plane flexural initial stiffness and ultimate capacity of joints. As thickness of reinforcement plate increases, the ductility of reinforced X-joints decreases. The concave and convex deformation of every specimen has good symmetry;as β increases, the yield and ultimate deformation of chord decrease.     

妙用“口诀”激活课堂教学

电子技术课是一门比较难学的技术基础课，如何改进教学方法，使课堂教学生动有趣，是一个很关键的问题。用“口诀”进行教学是一种较为有趣的教学方法。本文介绍用“口诀”作为教学内容的总结和开场白的几个实例及其所取得的效果。     

通信原理翻转课堂教学研究——以“通信基本概念”为例

通信原理是电子信息工程、通信工程专业学生必不可少的一门专业核心课程,"通信基本概念"是本课程的第一章的学习内容,这一章讲解的教学质量,对后续专业知识的学习将起到至关重要的作用。本文通过课前视频自学、课中重点分析、课后深入讨论三位一体的翻转课堂教学方式进行"通信基本概念"部分教学,实现了"以学生为中心"的自主学习,提高学生的综合素质。     

移动通信中语音编码技术的应用与发展

移动通信系统采取了多种行之有效的关键技术来提高系统抗衰落和抗干扰能力,语音编码技术即是其中一种。文章主要介绍了几代移动通信系统中使用的不同语音编码技术,旨在阐明语音编码技术基本原理及其重要作用。     

多载波调制体系VDSL系统中ADC问题的探讨

主要介绍了多载波调制体系VDSL系统中ADC精度对DMT系统的影响，给出了解决ADC问题的4种方案，并对这些解决方案进行了分析与比较。