LTELNMCC原理题库.pptVIP

* * * * * * * * * * It is a flat architecture, no controller node, that is no BSC or RNC. Most of the functionality handled by these nodes in 2G and 3G networks are now handled by the base station and a good example is controlling handovers of the terminals. Two new core nodes are introduced. The SGSN used in 2G/3G networks is converted to a Mobile Management Entity, MME. One of its responsibilities is to keep track of terminals in idle mode. A SGSN can be software upgraded to a MME and after that function as a combined SGSN and MME. Then we have the user data node, Packet Data Network and Serving Gateway node, P/S-GW node, which also can be a software upgrade of a current GGSN node. Also for CDMA software upgrades of core nodes can be done to support LTE. * * * * 资源分配结合规范，现有实现程度。集中式：优点调度开销小。确认二者的区别及各自的有缺点。分布式最小单位是RB. * 均衡技术可以补偿时分信道中由于多径效应而产生的ISI 频域调度部分的多用户分集增益改为频选调度增益。 灵活性弱。 减少了因多径时延带来的符号间干扰。 OFDM使用的是时域均衡 每个子载波的带宽是15kHz,信道的相干带宽为1MHz=1/5Ts,Ts=200ns,所以OFDM的每个子载波可看做平坦衰落信道。 * * * * * * DWPTS等时隙是否在FDD系统中也存在？用途？ * * * * * 备注：标识黄色背景的是什么意思？ 主要应用的是模式2、3、7 * [NOTE TO INSTRUCTOR – Slide has animation, click mouse to progress animation when the words Click appear ] As stated previously, the Self-Organising Network concept covers three different phases of the network life cycle; Self-configuration, self-optimisation and self-healing. These concepts will now be discussed in more detail. Click Self-Configuration Self-configuration process is defined as the process where newly deployed nodes are configured by automatic installation procedures to get the necessary basic configuration for system operation. This process works in pre-operational state. Pre-operational state is understood as the state from when the eNode B is powered up and has backbone connectivity until the RF transmitter is switched on. This is essential plug play behavior for new network elements. The key areas is automated deployment of new base stations, which covers following activities: · autom