• 主题
高级搜索  >
历史搜索 清空历史
首页> 外文会议>IEEE International Telecommunications Energy Conference >DC surge protection of remote radio units RRU or remote radio head RRH intelec® 2014 conference proceedings
【24h】

DC surge protection of remote radio units RRU or remote radio head RRH intelec® 2014 conference proceedings

机译：远程无线电单元RRU或远程无线电头端RRH intelec ® 2014会议程序的直流电涌保护

获取原文
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

Traditionally, cellular radio antennae were connected to base station radio equipment using coaxial feeders. Microwave radio antennae were ether connected with waveguides or coaxial cables, which will collectively be called feeders herein. The feeders would carry the baseband frequency and the RF signal. RF feeders have served the industry extremely well. However as the frequency and the bandwidth transmitted increases, the losses in the feeder and connectors became more significant. There is a limitation on the length of the RF feeder before losses become intolerable and the error rate significant. The next generation of (microwave) radio equipment utilized remote radio units close to the antennae which would convert the frequencies to an intermediate frequency and this could be transmitted more efficiently on smaller coax feeders with losses being less of a problem. Modern cellular and microwave equipment utilize remote radio unit RRU or remote radio head RRH which is fed from the base station via optical fiber. This eliminates the loss issues on feeders and allows transmission to occur at much higher frequencies with larger bandwidth. Power to the RRU cannot be transferred from the base station to RRU or RRH via the optical fiber. Hence, power is fed separately as DC on copper cables. The copper cables are either separate from the fiber or are a composite fiber-copper cable. The DC feed acts as a source of lightning surges back into the equipment room. More precaution needs to be taken on how to control these surges, than ever before. In traditional radio, damage to equipment would normally be limited to the radio equipment. In the modern scenario damage can occur to the rectifiers or the whole DC power system, which would jeopardize other equipment installed at the site. 1) Location of SPD The simple solution to this may seem like installing Transient Voltage Surge Suppressors (TVSS) or Surge Protective Devices (SPD) on the DC feeds. However, there are intricac- es that involve ground loops & voltage drops associated with cable lengths that need to be understood before choosing the correct location of SPD. This paper will discuss the possible location of the SPD and the benefit and disadvantages with each location presented. 2) Sizing of SPD There is guidance on the sizing of AC SPD in various standards, including IEEE C61.42, IEC61643 & ITU K56. There is some guidance on the sizing of SPD's for coaxial feeders and tower lights in ITU K56 guidelines. However the application of DC SPD on RRU is a relatively new concept and standards for sizing of these may not exist. The paper will look at methods of sizing AC SPD's and SPD's for traditional feeders and tower lights as a benchmark and propose suitable values for DC SPD for RRU. 3) Testing of SPD Finally, the application of SPD's in DC applications poses some unique challenges that are not present in AC applications. One such challenge is ensuring that the DC voltage present does not cause the SPD to get into continuous conduction at any time. In AC systems there are many voltage crossing and hence there is opportunity for SPD to get out of conduction. This paper will look at a test setup that simulates the DC application and demonstrate examples of results obtained.
机译：传统上，使用同轴馈线将蜂窝无线电天线连接到基站无线电设备。微波无线电天线与波导或同轴电缆以太连接，在本文中统称为馈线。馈线将携带基带频率和RF信号。射频馈线在整个行业中的表现非常出色。但是，随着频率和传输带宽的增加，馈线和连接器中的损耗变得更加明显。在RF馈线的长度受到限制之前，损耗就变得无法容忍且错误率显着。下一代（微波）无线电设备利用靠近天线的远程无线电单元，它将频率转换为中频，并且可以在较小的同轴馈线上更有效地传输，而损失的问题就更少了。现代蜂窝和微波设备使用远程无线电单元RRU或远程无线电头RRH，它们是通过光纤从基站馈送的。这消除了馈线上的损耗问题，并允许以更高的频率和更大的带宽进行传输。 RRU的电源无法通过光纤从基站传输到RRU或RRH。因此，电源在铜缆上分别作为直流电馈入。铜缆既可以与光纤分开，也可以是复合铜缆。直流馈电充当雷电浪涌回到机房的一种来源。与以往相比，在如何控制这些电涌方面需要采取更多的预防措施。在传统无线电中，对设备的损坏通常仅限于无线电设备。在现代情况下，整流器或整个直流电源系统可能会损坏，这会危害现场安装的其他设备。 1）SPD的位置对此的简单解决方案似乎是在DC馈源上安装了瞬态电压浪涌抑制器（TVSS）或电涌保护器（SPD）。但是，在选择正确的SPD位置之前，需要了解与电缆长度相关的接地环路和压降的复杂之处。本文将讨论SPD的可能位置以及每个位置的利弊。 2）SPD的大小在各种标准中都有关于AC SPD大小的指南，包括IEEE C61.42，IEC61643和ITU K56。 ITU K56指南中有一些有关同轴馈线和塔灯的SPD尺寸的指南。但是，DC SPD在RRU上的应用是一个相对较新的概念，可能不存在用于这些尺寸的标准。本文将以调整传统馈线和塔灯的AC SPD和SPD尺寸的方法为基准，并为RRU的DC SPD提出合适的值。 3）SPD的测试最后，在DC应用中SPD的应用带来了AC应用中不存在的一些独特挑战。这样的挑战之一是确保存在的直流电压在任何时候都不会导致SPD进入连续导通状态。在交流系统中，存在许多跨电压，因此SPD有机会脱离传导。本文将研究模拟DC应用的测试设置，并演示获得的结果的示例。

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号