广义频分复用系统在电力线通信中的运用

Generalized Frequency Division Multiplex for Power Line Communication System

在现有的电力线通信系统(Power Line Communication,PLC)中,正交频分复用(Orthogonal Frequency Divi-sion Multiplex,OFDM)由于能够有效地消除电力线系统中的脉冲噪声干扰、多径时延干扰和群时延干扰,已成为一种主要的技术手段。OFDM技术尽管具有上述优点,但却存在高峰值功率、循环前缀导致的频谱利用率受限等问题。相应地,与OFDM具有不同设计思路的、基于成形滤波器的广义频分复用系统(Generalized Frequency Division Multi-plex,GFDM)也就成为当前研究的热点。GFDM通过设计适合信道时延的成形滤波器,利用其时频聚焦性,可兼有抵抗字符间干扰(Inter Symbol Interference,ISI)和载波间干扰(Inter Carriers Interference,ICI)的能力,并可获得更高的频谱效率(无须循环前缀)。

Orthogonal frequency division multiplex（OFDM） is a good candidate for power line communication system,because it is effective against pulse noise,multipath delay and group delay.However,the drawbacks of the high peak-to-average power ratio and cyclic prefix lead OFDM system to have lower efficiency.Fortunately,Generalized Frequency Division Multiplex（GFDM） with good time-frequency localization can solve inter symbol interference（ISI） and inter carrier interference（ICI）.Meanwhile,GFDM has higher spectrum efficiency because of no cyclic prefix.