说明：  OFDM (Orthogonal frequency-division multiplexing, 正交频分复用) 是一种多载波调制技术。因其能有效对抗频率选择性衰落，克服信号符号间干扰
(OFDM (Orthogonal Frequency Division Multiplexing) is a type of multi-carrier modulation technique. It is able to effectively combat frequency selective fading and overcome interference between signal symbols.)