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Design, performances and application of the high frequency analog integrated phase-locked loop KD8041 are described in this paper. The PLL KD8041 consists of phase detector, voltage controled oscillation, low pass filter, amplifiers, vol. tage and current stabilizers, and temperature compendation network, etc. The operating frequency is 50MHz. It can be used in modern communications, frequency synthesis, automatic control and precision instrumentation, etc. 本文介绍高频模拟集成锁相环(PLL)KD8041的设计原理、性能指标及其应用。它由鉴相器、压控振荡器、低通滤波器、若干放大器、稳压稳流器及温度补偿电路所组成。其最高振荡频率为50MHz,可广泛应用于现代通讯、频率合成、自动控制及精密仪器仪表中。 The modern information society continuously demands for larger communication capacities.These demands can be met by developing higher telecommunication frequencies.With this goal and modern communication technology basing on satellite systems with reflector antennas,a new structural design concept of a satellite antenna reflector as an adaptive structural system is being developed.In this article the manufacturing of such a parabolic central focus sandwich... The modern information society continuously demands for larger communication capacities.These demands can be met by developing higher telecommunication frequencies.With this goal and modern communication technology basing on satellite systems with reflector antennas,a new structural design concept of a satellite antenna reflector as an adaptive structural system is being developed.In this article the manufacturing of such a parabolic central focus sandwich reflector of a diameter of 900mm with intermediate modulus carbon fibre/epoxy face sheets and aluminium honeycomb core with integrated actuators will be introduced.The fabrication of the actuator packages,the filament winding process and the assembly of the actuators will be presented.With this paper the authors intend to introduce this new design concept as a promising technique to realise lightweight,by means of active control thermally highly stable and economic reflector structures for future communicaiton applications. 现代信息社会越来越需要更大的通讯能力 ,这种需要可通过发展更高的远程通讯频率来满足 ,为实现此目的 ,使用发射天线的卫星通讯系统。德国宇航研究院结构力学研究所正在研制一种新的、用于卫星天线发射器的自适应结构体系。本文介绍了一种直径为 90 0毫米的抛物面型叠层发射器的制造工艺。该卫星天线发射器叠层材料为中等弹性模量的碳纤维——环氧树脂面板和带有集成激励控制驱动器的铝蜂窝夹芯。并将给出驱动器封装的制造 ,纤维缠绕过程和驱动器的装配方法。本文介绍了这一新的设计思想和具有高效控制 ,高热稳定性及经济的、重量轻的自适应智能天线反射器结构。 An L (2,1) labeling of a graph G is a function f from the vertex set V(G) to the set of all nonnegative integers such that |f(x)-f(y)|2 if d(x,y) =1 and |f(x)-f(y)| 1 if d(x,y) =2.The moving communication frequency assignment problem can be transformed into an L(2,1) labeling problem on a graph.The 2 lattice and relative graph are extended to the n lattice and relative graph,and the L(2,1) labelings of the n lattice and relative graph are given. 图G的L(2 ,1 )标号是一个从顶点集V(G)到非负整数集的函数f(x) ,使得若d(x ,y) =1 ,则|f(x) -f(y) | 2 ;若d(x ,y) =2 ,则 |f(x) -f(y) | 1 .移动通讯频率分配问题可以转化为图的L(2 ,1 )标号问题 .将 2 格图及相关图推广到n 格图及相关图 ,并给出了它们的L(2 ,1 )标号 .
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