基于AD9361的掌上型LTE RRU设计与开发

当前小体积远端射频单元（Remote Radio Unit,RRU）主要是皮站级别的Pico-RRU，其重量和体积仍然难以满足掌上型的要求。为此，采用高集成度的AD9361芯片来实现长期演进（Long Term Evolution，LTE）宽带收发信机功能，配合时钟同步模块、放大器模块和控制接口电路等一起构建低成本的掌上型RRU。主要解决了基于AD9516的时钟同步、低相位噪声设计和高灵敏度接收机设计三个技术难点，成功实现了掌上型、高性能、低成本的设计目标。整个RRU样机尺寸为18 cm×10 cm×2 cm，质量约500 g，量产成本千元以内。测试表明，该RRU下行误差向量幅度（Error Vector Magnitude，EVM）小于3%，优于3GPP要求的8%；10 MHz带宽时上行接收机灵敏度优于3GPP要求的-93.5 dBm。     

高速移动数据传输新标准IEEE 802.20

介绍了未来高速移动通信新标准IEEE802．20的总体概况，具体分析了IEEE802．20的技术特性、系统参考结构以及系统的组成模型，并对IEEE802．20标准前景分析与展望进行了详细描述。     

基于无线技术的仓储拣选作业流程再造方案分析

对传统的仓储拣选作业流程进行了研究分析,提出了基于无线技术的仓储拣选作业流程再造方案,并对两者进行了对比分析,阐述了再造后的拣选作业流程采用无线技术及其相关技术后的诸多优点及发展前景.     

MMS系统的原理结构与应用浅析

多媒体短信息服务(MMS)是目前短信息技术开发最高标准的一种.它最大的特色就是支持多媒体功能.MMS可即时实现终端到终端、终端到互联网或互联网到终端的信息传输,允许传输数据、文本、图像、音频、视频消息.本文对MMS的原理结构作了较为详细的分析,列举了MMS的几个其型应用例子.     

Spread spectrum of knowledge network based on information integration environment

The concept and the characteristic of spread spectrum technology of knowledge network based on information integration environment are given at first. And the basic principle of the wireless network of knowledge and information is recommended. Then a project alternatives using the spread spectrum technology and wireless network is given to build a across-the abroad knowledge network system.     

Pareto efficient allocation of an in-motion wireless charging infrastructure for electric vehicles in a multipath network

Electric vehicles (EV) use an eco-friendly technology that limits the greenhouse gas emissions of the transport sector, but the limited battery capacity and the density of the battery are the major barriers to the widespread adoption of EV. To mitigate this, a good method seems to be the innovative wireless charging technology called ‘On-Line EV (OLEV)’, which is a contactless electric power transfer technology. This EV technology has the potential to charge the vehicle’s battery dynamically while the vehicle is in motion. This system helps to reduce not only the size of the battery but also its cost, and it also contributes to extending the driving range before the EV has to stop. The high cost of this technology requires an optimal location of the infrastructure along the route. For this reason, the objective of this paper is to study the problem of the location of the wireless charging infrastructure in a transport network composed of multiple routes between the origin and the destination. To find a strategic solution to this problem, we first and foremost propose a nonlinear integer programming solution to reach a compromise between the cost of the battery, which is related to its capacity, and the cost of installing the power transmitters, while maintaining the quality of the vehicle’s routing. Second, we adapt the multi-objective particle swarm optimization (MPSO) approach to our problem, as the particles were robust in solving nonlinear optimization problems. Since we have a multi-objective problem with two binary variables, we combine the binary and discrete versions of the particle swarm optimization approach with the multi-objective one. The port of Le Havre is presented as a case study to illustrate the proposed methodology. The results are analyzed and discussed in order to point out the efficiency of our resolution method.     

基于物联网技术平台的O2O商业模式研究

在国家大力推进产业结构调整、信息化的压力下,物联网技术和O2O商业模式作为信息时代的新型生产力,在国内的普及率并不高。本文运用案例分析的方法通过研究大学生创业项目引入O2O商业模式的概念,并与物联网技术有机结合,把握两者之间优势互补的关系,提出两者创新应用,同时从商业模式构成要素的角度对该模式进行系统、深入分析,为中国现代农业信息化建设和结构调整提供了新思路。     

Limits to creative destruction and technologies in practice: the case of ham radio

Drawing on the structurationist notion of ‘technologies-in-practice’, this article analyses the different types of technological actions that users perform, after technological change, in order to keep a declining technology alive over time. The research question of the article is: How do technologies-in-practice based on the application of new technology hamper the creative destruction of old technology? The case study of ham radio technology and amateur radio operators is explored. The results of the investigation support the development of a technology-in-practice ‘experimentation’ and four inductive research propositions.     

基于“北斗一代”的Zigbee无线网关设计

为了解决野外多点数据采集无供电、布线复杂和通信困难的问题,提出了一种基于“北 斗一代”的Zigbee无线网关设计方案。采用MSP430F6438、CC2341微处理器和一体化的RDSS “北斗”射频芯片完成低功耗、小成本的硬件设计。通过增加SIM卡的数量,将网关转发“ 北斗”数据的频率降至最低的5 s,提高了网关的通信速率。通过软件设计实现了Zigbee无 线传感网络和“北斗一代”系统之间数据的透明交换。该方法已成功应用于野外油气井远程 监控系统中。     

采用喷泉码的无线协同多跳信息累积广播协议

为提高无线多跳广播的能量效率,提出了采用喷泉码的协同多跳信息累积广播 协议：令注水速率最大的节点进行发送,其发送功率由传输速率和注水速率决定。当有接收 节点成功接收时,再由更新后注水速率最大的节点发送。各发送节点采用不同的喷泉码进行 编码,使接收节点获得复用增益,并且节点可以接收可靠传输范围以外的信息并进行累积直 至成功译码。根据节点是否掌握全局网络信息,给出了集中式信息累积启发算法和分布式信 息累积算法,并且将本协议与现有的能量累积协议进行了比较,仿真结果表明所提协 议在能量效率上有较大的提高。