Method and apparatus for noise estimation in orthogonal frequency division multiplexing (OFDM) system

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 wk, where k is an integer between
• -
• N
• tap
• 2
• ⁢
• ⁢
• and
• ⁢
• ⁢
• N
• tap
• 2
• ,
• and Ntap is a positive integer greater than 1, 0<|wk|<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 wk;
• 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 wk generated by the channel estimation coefficient generation module, wherein the correction factor β is obtained based on the following formula:
• β=1+|w0|2−(w0*+w0)+α, where w0* is a conjugate value of w0, 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.