英语翻译Typical link to system level models utilized for the eva

英语翻译
Typical link to system level models utilized for the evaluation of multicarrier systems such as LTE are Exponential Effective SIR Mapping (EESM) and Packet Error Rate (PER) indicator.Such models can be used to obtain the effective SINR of the received TB to which afterwards the H-ARQ gains can then be added.
Although there are already extensions for EESM to deal with H-ARQ showing results for uncoded simulations,our proposed simulation-based model takes into account the whole LTE processing chain,providing a more tailored model for LTE.Details such as the number of new and systematic bits in each retransmission and the performance of the channel coding,which are specific to the LTE system are then taken into account.
Our model shows that,as expected,the highest SNR gains are observed for high modulation orders and ECRs,as IR performs at best in this region(see Fig.10).Up to a 12.75 dB improvement has been observed for CQI 15 (64-QAM,948 ECR).The relative mean square error (MSE) of the estimated SNR gains is shown in Table 3).As it can be seen,relative MSEs show errors below 1% except for the 64-QAM modulation.This high error is due to a mismatch of the model with the actual measured SNR gains for the last two CQI values (873 and 948 ECRs).

指数有效SIR映射（EESM）和包出错率（PER）指示器是用于诸如LTE等多载波系统评估的系统级模型的典型连接链路.我们可以利用这些模型来获得接收到的TB的有效SINR,并随后在其上加上H-ARQ增益.
尽管已有解决H-ARQ问题的扩展EESM 方案的非编码仿真结果的存在,但我们提出的这个基于仿真的模型考虑了整个LET处理链,进而给出一个更加简化的LET模型.而诸如每次重发的新码位和系统码位数量以及通道编码性能等这些LTE系统所特有的属性也会随后纳入考虑之中.
正如所预期的那样,在高调制水平（high modulation orders）和高ECR的情况下,这也是IRB性能表现最好的区域,我们的模型显示出了最高的SNR增益（见图10）.对于CQI 15 (64-QAM,948 ECR),SNR增益的改善可以高达12.75 dB.表3给出了估算的SRN增益的相对均方误差（MSE）.从表中可以看出,除了64-QAM调制的情况外,其他相对均方误差均低于1%.最后两个CQI值（873和948ECR）的高误差则是由于模型与实际测量的SNR增益之间的不匹配所造成的.