为了满足多样化场景下的通信需求,5G采用了以正交频分复用(orthogonal frequency division mul-tiplexing,OFDM)技术为基础的混合参数集系统。该系统将具有不同子载波间隔和循环前缀长度的OFDM符号在频域进行复用,同时服务不同场景下的...为了满足多样化场景下的通信需求,5G采用了以正交频分复用(orthogonal frequency division mul-tiplexing,OFDM)技术为基础的混合参数集系统。该系统将具有不同子载波间隔和循环前缀长度的OFDM符号在频域进行复用,同时服务不同场景下的用户。混合参数集系统中峰均比(peak-to-average power ratio,PAPR)过高的问题仍然存在,并且不同参数子信号叠加生成混合信号这一设计结构使得传统OFDM的PAPR抑制方法难以直接应用。基于预留子载波技术建立了混合参数集系统最小化PAPR的优化模型。利用时域核脉冲的单峰特性,根据混合信号的峰值位置同时在不同参数集中产生多个副本,之后叠加生成混合时域核脉冲进行峰值抵消。所提算法不需要在迭代中进行快速傅里叶逆变换(inverse fast Fourier transform,IFFT)/快速傅里叶变换(fast Fourier transform,FFT)操作,具有较低的计算复杂度。仿真结果表明,该算法有效降低了混合信号的PAPR。展开更多
Recently, FTTH （fiber to the home） is spreading rapidly, and communication technology has become an indispensable part in our lives. FTTH installers who build the infi＇astructure must correspond to the progress of ...Recently, FTTH （fiber to the home） is spreading rapidly, and communication technology has become an indispensable part in our lives. FTTH installers who build the infi＇astructure must correspond to the progress of technology while ensuring a high quality of installation, and it is struggling to its counterpart. The present study is undertaken in order to propose effective vocational ability development program for FTTH installers from the approach of their skill. They are information network cabling-related qualification system and competitions as the ability evaluation system. Then the author concludes that this program makes a contribution to improving their skill and maintaining the quality of the optical fiber network in analyzing some example of actual installation work and the measurement result of the OTDR（optical time domain reflect） meter.展开更多
文摘为了满足多样化场景下的通信需求,5G采用了以正交频分复用(orthogonal frequency division mul-tiplexing,OFDM)技术为基础的混合参数集系统。该系统将具有不同子载波间隔和循环前缀长度的OFDM符号在频域进行复用,同时服务不同场景下的用户。混合参数集系统中峰均比(peak-to-average power ratio,PAPR)过高的问题仍然存在,并且不同参数子信号叠加生成混合信号这一设计结构使得传统OFDM的PAPR抑制方法难以直接应用。基于预留子载波技术建立了混合参数集系统最小化PAPR的优化模型。利用时域核脉冲的单峰特性,根据混合信号的峰值位置同时在不同参数集中产生多个副本,之后叠加生成混合时域核脉冲进行峰值抵消。所提算法不需要在迭代中进行快速傅里叶逆变换(inverse fast Fourier transform,IFFT)/快速傅里叶变换(fast Fourier transform,FFT)操作,具有较低的计算复杂度。仿真结果表明,该算法有效降低了混合信号的PAPR。
文摘Recently, FTTH （fiber to the home） is spreading rapidly, and communication technology has become an indispensable part in our lives. FTTH installers who build the infi＇astructure must correspond to the progress of technology while ensuring a high quality of installation, and it is struggling to its counterpart. The present study is undertaken in order to propose effective vocational ability development program for FTTH installers from the approach of their skill. They are information network cabling-related qualification system and competitions as the ability evaluation system. Then the author concludes that this program makes a contribution to improving their skill and maintaining the quality of the optical fiber network in analyzing some example of actual installation work and the measurement result of the OTDR（optical time domain reflect） meter.
