说明：  　OFDM —— OFDM(Orthogonal Frequency Division Multiplexing)即正交频分复用技术，实际上OFDM是MCM Multi-CarrierModulation，多载波调制的一种。其主要思想是：将信道分成若干正交子信道，将高速数据信号转换成并行的低速子数据流，调制到在每个子信道上进行传输。此程序为ofdm仿真程序！
(OFDM- OFDM (Orthogonal Frequency Division Multiplexing) that is orthogonal frequency division multiplexing, OFDM is the fact MCM Multi-CarrierModulation, a multi-carrier modulation. The main idea is: The channel is divided into a number of orthogonal sub-channel, high-speed data signals into parallel low-speed sub-data stream, modulated to be transmitted in each sub-channel. This program is ofdm simulation program!)