Interference alleviation equalizing apparatus of multi-carrier communication system and method thereof

1. An apparatus for equalizing a received signal to generate an equalized signal, comprising:

a channel estimator for generating channel estimation values H′ j,k and H″ j,k , wherein j denotes a band index in a multi-carrier communication system and k denotes a subcarrier index in the band j,

according to a preamble symbol in the received signal and for generating a channel response value H j,k according to an average value of the channel estimation values, wherein H j,k =H′ j,k +H″ j,k /2;

an equalization circuit for equalizing the received signal according to the channel response value and an interference power estimate to generate the equalized signal; and

an interference power estimation circuit for generating the interference power estimate according to a hard decision value, the channel estimation values, and the received signal;

wherein the hard decision value corresponds to the equalized signal.

2. The apparatus of claim 1 , wherein the interference power estimation circuit comprises:

an error estimator for generating a reconstructed signal according to the channel response value and the hard decision value, and for generating an error amount according to a difference value between the reconstructed signal and the received signal; and

an interference computing unit for updating the interference power estimate according to the error amount and a weighting factor.

3. The apparatus of claim 1 , wherein the equalization circuit comprises:

a channel confidence value computing unit for generating a channel confidence value; and

an equalizing unit for equalizing the received signal according to the channel response value and the channel confidence value to generate the equalized signal.

4. The apparatus of claim 3 , wherein the channel confidence value computing unit adjusts the channel confidence value according to the interference power estimate.

5. The apparatus of claim 3 , wherein the channel confidence value computing unit generates the channel confidence value according to a weighting factor, the channel response value, and the interference power estimate.

6. The apparatus of claim 5 , wherein the channel confidence value computing unit adjusts the weighting factor according to the amount of the interference power estimate.

7. The apparatus of claim 1 being applied in a multi-carrier communication system.

8. An apparatus for equalizing a received signal to generate an equalized signal, comprising:

a channel estimator for generating channel estimation values H′ j,k and H″ j,k , wherein j denotes a band index in a multi-carrier communication system and k denotes a subcarrier index in the band j,

according to a preamble symbol in the received signal and for generating a channel response value H j,k according to an average value of the channel estimation valuses, wherein H j,k =H′ j,k +H″ j,k /2;

an equalization circuit for equalizing the received signal according to a channel confidence value and the channel response value to generate the equalized signal; and

an interference power estimation circuit for generating an interference power estimate according to the channel estimation values, wherein the channel confidence value corresponds to the interference power estimate.

9. The apparatus of claim 8 , wherein the equalization circuit comprises:

a channel confidence value computing unit for generating the channel confidence value according to a first weighting factor, the interference power estimate, and the channel response value.

10. The apparatus of claim 8 , wherein the channel confidence value computing unit is utilized for comparing the interference power estimate and a threshold limit value to generate the first weighting factor.

11. The apparatus of claim 8 , wherein the interference power estimation circuit comprises:

an error estimator for generating a reconstructed signal according to the channel response value and a hard decision value, and for generating an error amount according to a difference value between the reconstructed signal and the received signal, wherein the hard decision value corresponds to the equalized signal; and

an interference computing unit for updating the interference power estimate according to the error amount.

12. The apparatus of claim 8 , being applied in a multi-carrier communication system.

13. A method for equalizing a received signal to generate an equalized signal, comprising:

receiving the received signal and generating channel estimation values H′ j,k and H″ j,k , wherein j denotes a band index in a multi-carrier communication system and k denotes a subcarrier index in the band j, according to a preamble symbol in the received signal;

generating a channel response value H j,k according to an average value of the channel estimation valuses, wherein H j,k =H′ j,k +H″ j,k /2;

equalizing the received signal according to the channel response value and an interference power estimate to generate the equalized signal; and

generating and updating the interference power estimate according to a hard decision value, the channel response value, and the received signal;

wherein, the hard decision value corresponds to the equalized signal.

14. The method of claim 13 , wherein the step of generating and updating the interference power estimate comprises:

generating a reconstructed signal according to the channel response value and the hard decision value;

generating an error amount according to a difference value between the reconstructed signal and the received signal; and

updating the interference power estimate according to the error amount and a weighting factor.

15. The method of claim 13 , wherein the step of generating the equalized signal comprises:

adjusting a channel confidence value according to the interference power estimate; and

equalizing the received signal according to the channel response value and the channel confidence value to generate the equalized signal.

16. The method of claim 15 , wherein the step of adjusting the channel confidence value comprises comparing the interference power estimate and a threshold limit value to generate a weighting factor, and generating the channel confidence value according to the weighting factor, the channel response value, and the interference power estimate.

17. A method for equalizing a received signal to generate an equalized signal, comprising:

receiving the received signal and generating channel estimation values H′ j,k and H″ j,k , wherein j denotes a band index in a multi-carrier communication system and k denotes a subcarrier index in the band j, according to a preamble symbol in the received signal;

generating a channel response value H j,k according to an average value of the channel estimation valuses, wherein H j,k =H′ j,k +H″ j,k /2;

generating an interference power estimate according to the channel estimation value; and

equalizing the received signal according to a channel confidence value and the channel response value to generate the equalized signal, wherein the channel confidence value corresponds to the interference power estimate.

18. The method of claim 17 , further comprising:

generating the channel confidence value according to the first weighting factor, the interference power estimate, and the channel response value.

19. The method of claim 18 , wherein the step of generating the channel confidence value comprises comparing the interference power estimate and a threshold limit value to generate the first weighting factor.

20. The method of claim 17 , wherein the step of generating the interference power estimate comprises:

generating a reconstructed signal according to the channel response value and a hard decision value, wherein the hard decision value corresponds to the equalized signal;

generating an error amount according to a difference value between the reconstructed signal and the received signal; and

generating the interference power estimate according to a mean-square error of the channel estimation value.