Method and apparatus for equalizing signals
A system and apparatus are disclosed for a method and apparatus for equalizing signals. An apparatus that incorporates teachings of the present disclosure may include, for example, an equalizer having a channel estimation calculator for calculating a time domain channel estimation from a baseband signal, a Fast Fourier Transform processor for translating the time domain channel estimation to a frequency domain channel estimation, a tap weight calculator for calculating a frequency domain tap weight according to the frequency domain channel estimation, an inverse Fast Fourier Transform processor for translating the frequency domain tap weight calculation to a time domain tap weight calculation, and a filter for equalizing the baseband signal according to the time domain tap weight calculation.
1. A mobile device, comprising:
a transceiver operating in a wideband code division multiple access high speed downlink packet access communication system;
a processing system including a processor; and
a memory that stores executable instructions that, when executed by the processing system, facilitate performance of operations, the operations comprising:
calculating a time domain channel estimation from a baseband signal;
translating the time domain channel estimation to produce a frequency domain channel estimation;
performing a frequency domain tap weight calculation according to the frequency domain channel estimation;
translating the frequency domain tap weight calculation to a time domain tap weight calculation;
equalizing the baseband signal according to the time domain tap weight calculation to provide an equalized signal, wherein the equalizing is performed using an equalization technique corresponding to one of a Minimum Mean Squared Error (MMSE) equalizer, a Decision Feedback (DF) equalizer, a Least Mean Square (LMS) equalizer, or a Recursive Least Square (RLS) equalizer; and
restoring signal integrity to the baseband signal based on the equalized signal, wherein the restoring results in a restored baseband signal.
2. The mobile device of claim 1 , wherein a selected equalization technique corresponds to the Least Mean Square (LMS) equalizer.
3. The mobile device of claim 1 , further comprising an audio system, wherein the audio system is configured to intercept or convey audible signals.
4. The mobile device of claim 3 , wherein the operations further comprise conveying the audible signals according to the restored baseband signal.
5. The mobile device of claim 1 , wherein the operations further comprise converting a carrier signal to the baseband signal, wherein the mobile device comprises a cellular phone, and wherein the mobile device comprises an antenna coupled to the transceiver.
6. The mobile device of claim 1 , wherein the operations further comprise: (a) applying a Fast Fourier Transform to the time domain channel estimation to produce the frequency domain channel estimation; and (b) applying an inverse Fast Fourier Transform to the frequency domain tap weight calculation to produce the time domain tap weight calculation.
7. The mobile device of claim 6 , further comprising a display, wherein the operations further comprise conveying visual signals according to the restored baseband signal.
8. A non-transitory machine-readable storage medium, comprising executable instructions that, when executed by a processing system including a processor, facilitate performance of operations, the operations comprising:
calculating a time domain channel estimation from a baseband signal;
translating the time domain channel estimation to produce a frequency domain channel estimation;
performing a frequency domain tap weight calculation according to the frequency domain channel estimation;
translating the frequency domain tap weight calculation to a time domain tap weight calculation;
equalizing the baseband signal according to the time domain tap weight calculation to provide an equalized signal, wherein the equalizing is performed using an equalization technique corresponding to one of a Minimum Mean Squared Error (MMSE) equalizer, a Decision Feedback (DF) equalizer, a Least Mean Square (LMS) equalizer, or a Recursive Least Square (RLS) equalizer; and
restoring signal integrity to the baseband signal based on the equalized signal, wherein the restoring results in a restored baseband signal.
9. The non-transitory machine-readable storage medium of claim 8 , wherein the operations further comprise applying a Fast Fourier Transform to the time domain channel estimation to produce the frequency domain channel estimation.
10. The non-transitory machine-readable storage medium of claim 8 , wherein the operations further comprise applying an inverse Fast Fourier Transform to the frequency domain tap weight calculation to produce the time domain tap weight calculation.
11. The non-transitory machine-readable storage medium of claim 8 , wherein the equalizing comprises averaging, and wherein the averaging is performed from one frame to a next frame.
12. The non-transitory machine-readable storage medium of claim 8 , wherein the operations further comprise converting a carrier signal to the baseband signal, and wherein the carrier signal comprises one of a data signal, a video signal, an audio signal, or a combined video and audio signal.
13. The non-transitory machine-readable storage medium of claim 8 , wherein the operations further comprise conveying audible signals according to the restored baseband signal.
14. The non-transitory machine-readable storage medium of claim 8 , wherein the operations further comprise conveying visual signals according to the restored baseband signal.
15. A method, comprising:
calculating, by a processing system including a processor, a time domain channel estimation from a baseband signal;
translating, by the processing system, the time domain channel estimation to produce a frequency domain channel estimation;
performing, by the processing system, a frequency domain tap weight calculation according to the frequency domain channel estimation;
translating, by the processing system, the frequency domain tap weight calculation to a time domain tap weight calculation;
equalizing, by the processing system, the baseband signal according to the time domain tap weight calculation to provide an equalized signal, wherein the equalizing is performed using an equalization technique corresponding to one of a Minimum Mean Squared Error (MMSE) equalizer, a Decision Feedback (DF) equalizer, a Least Mean Square (LMS) equalizer, or a Recursive Least Square (RLS) equalizer; and
restoring, by the processing system, signal integrity to the baseband signal based on the equalized signal, wherein the restoring results in a restored baseband signal.
16. The method of claim 15 , further comprising applying a Fast Fourier Transform to the time domain channel estimation to produce the frequency domain channel estimation.
17. The method of claim 15 , further comprising applying an inverse Fast Fourier Transform to the frequency domain tap weight calculation to produce the time domain tap weight calculation.
18. The method of claim 15 , wherein, in the equalizing, averaging is performed from one frame to a next frame.
19. The method of claim 15 , further comprising converting, by the processing system, a carrier signal to the baseband signal, wherein the carrier signal comprises one of a data signal, a video signal, an audio signal, or a combined video and audio signal.
20. The method of claim 15 , further comprising conveying, by the processing system, audible signals according to the restored baseband signal.