OFDM的采样频率怎么确定啊？

子载波数×子载波间隔

【 在 piaopiaoSun 的大作中提到: 】 : 子载波数×子载波间隔 应该是IFFT点数 * 子载波间隔 譬如LTE中，20M带宽，每子载波15KHz，总共约1200子载波，而IFFT点数2048， 采样频率= 2048 * 15000； 子载波总数一般不等于IFFT点数

the critical sampling frequency is N*deltaf N: subchannel number. the larger amount of IFFT number(dummy subchannel) is due to some other aims. 【 在 tiaotiaoyu 的大作中提到: 】 : 应该是IFFT点数 * 子载波间隔 : 譬如LTE中，20M带宽，每子载波15KHz，总共约1200子载波，而IFFT点数2048， : 采样频率= 2048 * 15000； : ...................

【 在 smequi 的大作中提到: 】 : the critical sampling frequency is N*deltaf : N: subchannel number. : the larger amount of IFFT number(dummy subchannel) is due to some other aims. The ratio N/Nc, could be seen as the over-sampling of the timediscrete OFDM signal. For 3GPP LTE the number of subcarriers Nc is approximately 600 in case of a 10MHz spectrum allocation. The IFFT size can then, for example, be selected as N =1024. This corresponds to a sampling rate fs =N ·f =15.36 MHz, where f =15 kHz is the LTE subcarrier spacing. Sampling frequency is exactly defined according to the number of IFFT points N, no matter how many subcarriers there map to IFFT. Of course, provided no over sampling exists, sampling frequency will be defined by Nc. The critical parameter is N rather than Nc.

Agree. actually,the reason why i define Nc as a critical parameter is from a theoretic view.That is, the dummy subchannels,N-Nc, are not used to transmit data,so we can design a algorithm working at a sampling frequency of Nc related. 【 在 tiaotiaoyu 的大作中提到: 】 : : The ratio N/Nc, could be seen as the over-sampling of the timediscrete OFDM signal. For 3GPP LTE the number of subcarriers Nc is approximately 600 in case of a 10MHz spectrum allocation. The IFFT size can then, for example, be selected as N =1024. This corresponds to a sampling rate fs =N ·f =15.36 MHz, where f =15 kHz is the LTE subcarrier spacing. : Sampling frequency is exactly defined according to the number of IFFT points N, no matter how many subcarriers there map to IFFT. Of course, provided no over sampling exists, sampling frequency will be defined by Nc. : ...................