Description: 由MATLAB程序产生2Gbi/s的基带OFDM信号先将2^15-1个伪随机序列映射到256个进行4QAM编码调制的子载波上，编码后的OFDM符号再经过IFFT变换将其转换为时域波形，接着添加6.4ns的循环前缀（CP），产生的数据波形再装载到Tektronix任意波形发生器（AWG）中，产生2Gbit/s的基带OFDM信号。基带OFDM信号频谱示意图如图3所示。其中包括256个OFDM子载波256个子载波中200个子信道用来传送数据信号，27个高频和28个低频子信道为了过采样的需要置0，OFDM频谱中最中间的那个子信道由于基带信号的直流成分大也被置0。-Generated by the MATLAB program 2Gbi/s baseband OFDM signal the first 2 ^ 15-1 pseudo-random sequence is mapped to 256 for 4QAM code modulation subcarriers, OFDM symbol after the re-encoded after IFFT transformation to convert it too domain waveform, and then add 6.4ns the cyclic prefix (CP), the data generated by Tektronix waveform and then loaded into the arbitrary waveform generator (AWG), resulting in 2Gbit/s baseband OFDM signal. Schematic diagram of the baseband OFDM signal spectrum shown in Figure 3. Including 256 sub-carrier OFDM subcarriers 256, 200 subchannels used to transmit data signals, 27 high and 28 low-frequency sub-channel over-sampling of the need to set 0, OFDM spectrum in the most middle of the baseband sub-channel as large DC component signal is also set to 0. Platform: |
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Author:QQ |
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