Method and system for adjusting DC offset slice point in an RF receiver
View Patent ↗A method for adjusting a DC offset slice point in an RF receiver is provided and may comprise estimating DC offset using a combination of fast tracking of an input signal and slow tracking of an input signal. If both are used, the fast tracking may be executed prior to executing the slow tracking. The fast tracking may acquire synchronizing signals transmitted before a payload. Additionally, noise tolerance may be increased in the fast tracking and the slow tracking by using tracking envelopes. The fast tracking may average acquisition envelopes and tracking envelopes using a fast tracking weighting factor to a sum of the acquisition envelopes and a slow tracking weighting factor to a sum of the tracking envelopes. Additionally, the slow tracking may average the tracking envelopes.
1. A method for direct current (DC) offset compensation in a receiver, the method comprising:
estimating DC offset using fast tracking and slow tracking wherein:
said fast tracking uses positive and negative acquisition envelopes which correspond to a first estimation of maxima and minima of an input signal;
said fast tracking uses positive and negative tracking envelopes which correspond to a second estimation of said maxima and minima of said input signal; and
said slow tracking uses said positive and negative tracking envelopes; and
said positive and negative acquisition envelopes respond more quickly to changes in said input signal than do said positive and negative tracking envelopes; and
adjusting a DC offset slice point based on said estimating.
2. The method according to claim 1 , comprising executing said fast tracking prior to executing said slow tracking.
3. The method according to claim 1 , comprising acquiring synchronizing signals transmitted before a payload via said fast tracking.
4. The method according to claim 1 , comprising averaging said acquisition envelopes and said tracking envelopes for said fast tracking.
5. The method according to claim 4 , comprising applying a fast tracking weighting factor to a sum of said positive acquisition envelope and said negative acquisition envelope.
6. The method according to claim 4 , comprising applying a slow tracking weighting factor to a sum of said positive tracking envelope and said negative tracking envelope.
7. The method according to claim 1 , comprising averaging said positive and negative tracking envelopes for said slow tracking.
8. The method according to claim 7 , comprising applying a slow tracking weighting factor to a sum of said positive and negative tracking envelopes.
9. A machine-readable storage having stored thereon, a computer program having at least one code section for DC offset compensation, the at least one code section being executable by a machine for causing the machine to perform steps comprising:
estimating DC offset using fast tracking and slow tracking wherein:
said fast tracking uses positive and negative acquisition envelopes which correspond to a first estimation of maxima and minima of an input signal;
said fast tracking uses positive and negative tracking envelopes which correspond to a second estimation of said maxima and minima of said input signal; and
said slow tracking uses said positive and negative tracking envelopes; and
said positive and negative acquisition envelopes respond more quickly to changes in said input signal than do said positive and negative tracking envelopes; and
adjusting a DC offset slice point based on said estimating.
10. The machine-readable storage according to claim 9 , wherein the at least one code section comprises code for executing said fast tracking prior to executing said slow tracking.
11. The machine-readable storage according to claim 9 , wherein the at least one code section comprises code for acquiring synchronizing signals transmitted before a payload via said fast tracking.
12. The machine-readable storage according to claim 9 , wherein the at least one code section comprises code for averaging said acquisition envelopes and said tracking envelopes for said fast tracking.
13. The machine-readable storage according to claim 12 , wherein the at least one code section comprises code for applying a fast tracking weighting factor to a sum of said positive acquisition envelope and said negative acquisition envelope.
14. The machine-readable storage according to claim 12 , wherein the at least one code section comprises code for applying a slow tracking weighting factor to a sum of positive said tracking envelope and said negative tracking envelope.
15. The machine-readable storage according to claim 9 , wherein the at least one code section comprises code for averaging said positive and negative tracking envelopes for said slow tracking.
16. The machine-readable storage according to claim 15 , wherein the at least one code section comprises code for applying a slow tracking weighting factor to a sum of said positive and negative tracking envelopes.
17. A system for processing a signal, the system comprising:
one or more circuits in a receiver, wherein said one or more circuits are operable to:
estimate DC offset using fast tracking and slow tracking wherein:
said fast tracking uses positive and negative acquisition envelopes which correspond to a first estimation of maxima and minima of an input signal;
said fast tracking uses positive and negative tracking envelopes which correspond to a second estimation of said maxima and minima of said input signal; and
said slow tracking uses said positive and negative tracking envelopes; and
said positive and negative acquisition envelopes respond more quickly to changes in said input signal than do said positive and negative tracking envelopes; and
adjusting a DC offset slice point based on said estimating.
18. The system according to claim 17 , wherein said one or more circuits are operable to execute said fast tracking prior to executing said slow tracking.
19. The system according to claim 17 , wherein said one or more circuits are operable to use said fast tracking to acquire synchronizing signals transmitted before a payload.
20. The system according to claim 17 , wherein said one or more circuits are operable to average said acquisition envelopes and said tracking envelopes for said fast tracking.
21. The system according to claim 20 , wherein said one or more circuits are operable to apply a fast tracking weighting factor to a sum of said positive acquisition envelope and said negative acquisition envelope.
22. The system according to claim 20 , wherein said one or more circuits are operable to apply a slow tracking weighting factor to a sum of said positive tracking envelope and said negative tracking envelope.
23. The system according to claim 17 , wherein said one or more circuits are operable to average said positive and negative tracking envelopes for said slow tracking.
24. The system according to claim 23 , wherein said one or more circuits are operable to apply a slow tracking weighting factor to a sum of said positive and negative tracking envelopes.