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 device, comprising:
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:
determining, based upon a signal, a time domain channel estimation;
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; and
performing an equalization of the signal based upon the time domain tap weight calculation to provide an equalized signal, wherein the equalization 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.
2. The device of claim 1 , wherein the operations further comprise:
applying a Fast Fourier Transform to the time domain channel estimation to produce the frequency domain channel estimation; and
applying an inverse Fast Fourier Transform to the frequency domain tap weight calculation to produce the time domain tap weight calculation.
3. The device of claim 1 , wherein the signal is a baseband signal, and wherein the equalization restores signal integrity to the baseband signal.
4. The device of claim 1 , wherein the device is a mobile device, wherein the mobile device comprises a cellular phone, and wherein the cellular phone comprises an antenna coupled to a transceiver.
5. The device of claim 4 , wherein the transceiver operates in a wideband code division multiple access communication system.
6. The device of claim 1 , wherein a selected equalization technique corresponds to the Least Mean Square (LMS) equalizer.
7. The device of claim 1 , wherein the signal is a baseband signal, and wherein the operations further comprise converting a carrier signal to the 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:
determining from a signal a time domain channel estimation;
producing a frequency domain channel estimation by translating the time domain channel estimation;
performing, based upon the frequency domain channel estimation, a frequency domain tap weight calculation;
translating the frequency domain tap weight calculation to a time domain tap weight calculation; and
providing, via equalizing of the signal according to the time domain tap weight calculation, 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.
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 signal is a baseband signal, and wherein the equalizing restores signal integrity to the baseband signal.
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 signal is a baseband signal, and wherein the operations further comprise converting a carrier signal to the baseband signal.
13. The non-transitory machine-readable storage medium of claim 12 , wherein the carrier signal comprises one of a data signal, a video signal, an audio signal, or a combined video and audio signal.
14. The non-transitory machine-readable storage medium of claim 8 , wherein the processing system is in a mobile device, wherein the mobile device comprises a cellular phone, wherein the cellular phone comprises a transceiver, and wherein the transceiver operates in a high speed downlink packet access communication system.
15. 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.
16. A method, comprising:
obtaining, by a processing system including a processor, a time domain channel estimation, wherein the time domain channel estimation is obtained from a signal;
obtaining, by the processing system, a frequency domain channel estimation by translating the time 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; and
performing an equalization, by the processing system, of the signal, wherein the equalization is provided according to the time domain tap weight calculation to provide an equalized signal, wherein the equalization 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.
17. The method of claim 16 , wherein the signal is a baseband signal, and wherein the equalization restores signal integrity to the baseband signal.
18. The method of claim 16 , wherein the signal is a baseband signal, wherein the method further comprises converting, by the processing system, 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.
19. The method of claim 16 , wherein the processing system is in a mobile device, wherein the mobile device comprises a cellular phone, and wherein the cellular phone comprises a transceiver.
20. The method of claim 16 , further comprising:
applying a Fast Fourier Transform to the time domain channel estimation to produce the frequency domain channel estimation; and
applying an inverse Fast Fourier Transform to the frequency domain tap weight calculation to produce the time domain tap weight calculation.