Research and Design of a Routing Protocol in Large-Scale Wireless Sensor Networks

无线传感器网络，作为全球未来十大技术之一，集成了传感器技术、嵌入式计算技术、分布式信息处理和自组织网技术，可实时感知、采集、处理、传输网络分布区域内的各种信息数据，在军事国防、生物医疗、环境监测、抢险救灾、防恐反恐、危险区域远程控制等领域具有十分广阔的应用前景。 本文研究分析了无线传感器网络的已有路由协议，并针对大规模的无线传感器网络设计了一种树状路由协议，它根据节点地址信息来形成路由，从而简化了复杂繁冗的路由表查找和维护，节省了不必要的开销，提高了路由效率，实现了快速有效的数据传输。 为支持此路由协议本文提出了一种自适应动态地址分配算——ADAR（AdaptiveDynamicAddre...As one of the ten high technologies in the future, wireless sensor network, which is the integration of micro-sensors, embedded computing, modern network and Ad Hoc technologies, can apperceive, collect, process and transmit various information data within the region. It can be used in military defense, biomedical, environmental monitoring, disaster relief, counter-terrorism, remote control of haz...学位：工学硕士院系专业：信息科学与技术学院通信工程系_通信与信息系统学号：2332007115216

Recent developments of the European XFEL LLRF system

The European X-ray free electron laser (XFEL) [1] comprised more than 800 TESLA-type super-conducting accelerator cavities which are driven by 25 high-power multibeam klystrons. For reliable, reproducible and maintainable operation of the linear accelerator (linac), the low-level radio frequency (LLRF) system will process more than 3000 RF channels. Furthermore, stable FEL operation demands field stability better than 0.01 deg. in phase and 0.01 % in amplitude. To cope with these challenges, the LLRF system is developed on a MTCA.4 [2] platform. In this paper, we give an update on the latest electronics developments, improvements of the feedback controller algorithm and measurement results at FLASH. Copyright © 2013 by JACoW- cc Creative Commons Attribution 3.0 (CC-BY-3.0).status: publishe

Performance of the MTCA.4 Based LLRF System at FLASH

The Free Electron Laser in Hamburg (FLASH) is the firstlinac which is equipped with a MicroTCA.4 based low levelRF control system. Precise regulation of RF fields is essen-tial for stable and reproducible photon generation. FLASHbenefits from the performance increase using the new devel-opments like, accurate and precise field detection devices.Further enormous increase of processing capabilities allowfor more sophisticated controller applications which betterthe overall performance of the regulation

Operation Experiences with the MICROTCA.4-based LLRF Control System at FLASH

The Free-Electron Laser in Hamburg (FLASH) at Deutsches Elektronen-Synchrotron (DESY), Hamburg Germany is a user facility providing ultra-short, femtosecond laser pulses up to the soft X-ray wavelength range. For the precise regulation of the radio frequency (RF) fields within the 60 superconducting cavities, which are organized in 5 RF stations, digital low level RF (LLRF) control systems based on the MTCA.4 standard were implemented in 2013. Until now experiences with failures potentially due to radiation, overheating, and ageing as well as with the general operation of the control systems have been gained. These have a direct impact on the operation and on the performance of FLASH and will allow future improvements. The lessons learned are not only important for FLASH but also in the scope of European X-ray Free-Electron Laser (X-FEL), which will be operated with the same LLRF control system

The European XFEL LLRF System

The European X-Ray free electron laser accelerator consists of 808 superconducting cavities grouped in 25 RF stations. The challenges associated with the size and complexity of this accelerator require a high-precision, modular and scalable low level RF (LLRF) system. The Micro TCA technology (MTCA.4) was chosen to support this system and adapted for RF standards. State-of-the-art hardware development in close collaboration with the industry allowed for the system continuity and maintainability. The complete LLRF system design is now in its final phase and the designed hardware was installed and commissioned at FLASH. The MTCA.4 LLRF architecture and system performance results will be shown. Operation strategies and future automation algorithms for performance optimization will also be presented in this paper. Copyright © 2012 by IEEE.status: publishe

European XFEL RF Gun Commissioning and LLRF Linac Installation

The European x-ray free electron laser (XFEL) is based on a 17.5 GeV super conducting pulsed linac and is scheduled to deliver its first beam in 2016. The first component of its accelerator chain, the RF gun, was installed in fall of 2013 and its commissioning is underway. This contribution gives an update on the low level radio frequency (LLRF) system development and installation for the XFEL. In particular, the installation, performance and conditioning results of the RF gun are presented. The subsequent steps toward LLRF components mass-production, testing and installation for the XFEL linac are also explained