基于圆形阵列的OAM波束产生系统设计与实现

针对目前轨道角动量(Orbital Angular Momentum,OAM)波束发生器模态单一、设计复杂等问题,设计并实现了一种在X频段内产生可调OAM波束的均匀圆形阵列天线。天线为半径60 mm的圆盘,由8个阵元组成,阵元采用微带天线设计,同轴馈电,在中心频率处回波损耗达-51.5 dB,S_(11)<-10 dB的工作带宽为9.6~10.5 GHz。仿真和实测结果表明,天线可通过调节相位产生7种不同模态的涡旋电磁波,产生OAM为+1的涡旋电磁波纯度可达90%。通过误差分析发现,低模态数的涡旋电磁波对幅度和相位误差具有很好的抗干扰能力,这为利用涡旋电磁波实现目标探测和提高信道容量奠定了基础。

关于光缆线路自动监测系统分析

随着光缆数量的增加以及早期敷设光缆的老化,光缆线路的故障次数在不断增加。传统的光缆线路维护管理模式的故障查找困难,排障时间长,影响通信网的正常工作,每年因通信光缆故障而造成的经济损失巨大。因此,实施对光缆线路的实时监测与管理,动态地观察光缆线路传输性能的劣化情况,及时发现和预报光缆隐患,以降低光缆阻断的发生率,缩短光缆的故障显得至关重要。

A Stream Control Transmission Protocol Based OAM System of 3G Cellular Network

OAM (Operations, Administration and Maintenance) system is a very impo rtant component of 3G cellular network. In order to acquire overall managemen t, fast response and steady operation, an SCTP (Stream Control Transmission Prot ocol) based OAM, i.e., SOAM system was proposed. SOAM implements new characters of SCTP such as multi-stream, enforced SACK and heartbeat mechanism on its tran sport layer. These characters help SOAM decrease the message transmission delay and accelerate the link failure detection. Besides, a new component named SOAM agent was introduced to improve the operation efficiency of SOAM. The experim ental results prove the proposed SOAM system achieves better performance on sign aling transmission compared with conventional TCP based OAM system.

单原子微波激射器中场的位相演化特征

利用Pegg－Barnett位相理论和Jaynes－Cummings模型研究单原子微波激射器中场的位相演化特性，具体计算了初始光场是真空场时，场的位相几率分布函数与位相涨落．

电力系统中的光缆线路自动监测技术

光缆线路自动监测技术集计算机技术、通信技术和光电技术为一体,它具有多种优点,正越来越广泛地应用于各行各业。这项技术在电力系统也受到关注,它能在电力通信调度系统中发挥重要的作用及具有广阔的发展前景。