Patent ID: 8787473

Claim:
An apparatus for performing noise estimation in an orthogonal frequency division multiplexing system comprising: a channel estimation coefficient generation module, a channel estimation module and a noise estimation calculation module connected to each other in sequence, a correction factor calculation module connected to an output of the channel estimation coefficient generation module, and a correction module connected to both the correction factor calculation module and noise estimation calculation module; wherein the channel estimation coefficient generation module is configured to generate a channel estimation coefficient w k , where k is an integer between - N tap 2 ⁢ ⁢ and ⁢ ⁢ N tap 2 , and N tap is a positive integer greater than 1, 0<|w k |<1; the channel estimation module is configured to calculate a channel estimation based on a received signal on a subcarrier of an orthogonal frequency division multiplexing symbol and the channel estimation coefficient w k ; the noise estimation calculation module is configured to calculate a noise estimation based on the received signal on the subcarrier of the orthogonal frequency division multiplexing symbol and the channel estimation; the correction factor calculation module is configured to calculate a correction factor β based on the channel estimation coefficient w k generated by the channel estimation coefficient generation module, wherein the correction factor β is obtained based on the following formula: β=1+|w 0 | 2 −(w 0 *+w 0 )+α, where w 0 * is a conjugate value of w 0 , and α is a residual noise correction factor, 0<α<1; and the correction module is configured to correct the noise estimation output by the noise estimation calculation module based on the correction factor β.