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随着数据通信与多媒体业务需求的发展,适应移动数据、移动计算及移动多媒体运作需要的第四代移动通信开始兴起,国际电信联盟(ITU)定义了4G的标准——符合100Mbps传输数据的速度,达到这个标准的通信技术,理论上都可以称之为4G。不过由于这个极限峰值的传输速度要建立在大于20MHz的带宽系统上,几乎没有运营商可以做得到,所以ITU将LTE-TDD、LTE-FDD、Wi MAX以及HSPA+四种技术定义于现阶段4G的范畴。与传统的RS485总线型门禁系统不同,网络门禁管理系统采用了TCP/IP网络通讯模式,由于系统自带TCP/IP通讯端口,可充分利用现场的TCP/IP以太网网络环境实现门禁管理主机与控制器之间的通讯,因此施工、调试、布线都非常简单,能最大限度地减少对原有建筑的破坏,降低工程造价,后期维护检修也较方便,所以已被越来越多的用户所采纳。4G技术正为移动网络门禁的革新带来无限想象的空间,为特殊、恶劣环境(如山区)等的使用带来福音。
With the development of data communications and multimedia services, the fourth generation of mobile communications that meet the needs of mobile data, mobile computing and mobile multimedia services are beginning to emerge. The International Telecommunication Union (ITU) has defined the 4G standard - in line with 100Mbps data transmission speed , To achieve this standard of communication technology, in theory, can be called 4G. However, since the transmission speed of this extreme peak is based on a bandwidth system of more than 20MHz and few operators can do it, ITU defines four technologies of LTE-TDD, LTE-FDD, WiMAX and HSPA + at this stage category. Different from the traditional RS485 bus-based access control system, the access control system of the network adopts the TCP / IP network communication mode. Since the system comes with TCP / IP communication port, it can make full use of the on-site TCP / IP Ethernet network environment to achieve access control host and Therefore, the construction, commissioning and wiring are very simple. It can minimize the damage to the original building and reduce the construction cost. It is also convenient for the later maintenance and inspection. Therefore, it has been more and more users adoption. 4G technology is bringing unlimited imagination to the innovation of access control in mobile networks, bringing good news for the use of special and harsh environments (such as mountainous areas).