Method and system for WCDMA power amplifier closed loop power control
Methods and systems for WCDMA power amplifier closed loop power control are disclosed and may include determining a magnitude of an output RF signal generated by a power amplifier (PA), and configuring a gain of a PGA coupled to an input of the PA via closed-loop feedback to maintain a desired magnitude of the output RF signal. The closed-loop feedback architecture may include a slot-based and/or a real time-based control. A signal proportional to the output signal may be generated by an envelope detector. The signal generated by the envelope detector may be utilized to generate a root-mean-squared (RMS) value. The gain of the PGA may be configured by comparing the RMS value to a desired magnitude of the output signal over a time slot and/or utilizing a real time error signal generated by subtracting the signal proportional to the magnitude of the output signal from a desired magnitude.
1. A method for processing signals, the method comprising:
in a wireless transmitter:
determining a magnitude of an output RF signal generated from a power amplifier; and
configuring a gain of a PGA coupled to an input of said power amplifier via closed-loop feedback to maintain a desired magnitude of said output RF signal, wherein said closed loop feedback comprises a slot-based control of said magnitude of said output RF signal.
2. The method according to claim 1 , wherein said closed loop feedback comprises a real time-based control of said magnitude of said output RF signal.
3. The method according to claim 1 , comprising generating a signal proportional to said magnitude of said output RF signal via an envelope detector.
4. The method according to claim 3 , comprising filtering said generated signal that is proportional to said magnitude of said output RF signal.
5. The method according to claim 3 , comprising generating a root-mean-squared (RMS) value of said generated signal that is proportional to said magnitude of said output RF signal.
6. The method according to claim 5 , comprising:
comparing said generated RMS value to a desired magnitude of said RF output signal over a time slot; and
configuring said gain of said PGA based on said comparison.
7. The method according to claim 3 , comprising generating a real time error signal by subtracting said signal proportional to said magnitude of said output RF signal from a desired magnitude of said output RF signal.
8. The method according to claim 7 , comprising configuring said gain of said PGA utilizing said generated real time error signal.
9. The method according to claim 3 , wherein said envelope detector comprises a diode.
10. A system for processing signals, the system comprising:
one or more circuits for use in a wireless transmitter, wherein said one or more circuits comprise a power amplifier and a programmable gain amplifier, and said one or more circuits are operable to determine a magnitude of an output RF signal generated from said power amplifier; and
said one or more circuits are operable to configure a gain of said PGA coupled to an input of said power amplifier via closed-loop feedback to maintain a desired magnitude of said output RF signal, wherein said closed loop feedback comprises a slot-based control of said magnitude of said output RF signal.
11. The system according to claim 10 , wherein said closed loop feedback comprises real time-based control of said magnitude of said output RF signal.
12. The system according to claim 10 , wherein said one or more circuits comprise an envelope detector, and said one or more circuits are operable to generate a signal proportional to said magnitude of said output RF signal via an envelope detector.
13. The system according to claim 12 , wherein said one or more circuits are operable to filter said generated signal that is proportional to said magnitude of said output RF signal.
14. The system according to claim 12 , wherein said one or more circuits are operable to generate a root-mean-squared (RMS) value of said generated signal that is proportional to said magnitude of said output RF signal.
15. The system according to claim 14 , wherein said one or more circuits are operable to:
compare said generated RMS value to a desired magnitude of said RF output signal over a time slot; and
configure said gain of said PGA based on said comparison.
16. The system according to claim 12 , wherein said one or more circuits are operable to generate a real time error signal by subtracting said signal proportional to said magnitude of said output RF signal from a desired magnitude of said output RF signal.
17. The system according to claim 16 , wherein said one or more circuits are operable to configure said gain of said PGA utilizing said generated real time error signal.
18. The system according to claim 12 , wherein said envelope detector comprises a diode.
19. A method for processing signals, the method comprising:
in a wireless transmitter:
determining a magnitude of an output RF signal generated from a power amplifier;
configuring a gain of a PGA coupled to an input of said power amplifier via closed-loop feedback to maintain a desired magnitude of said output RF signal; and
generating a signal proportional to said magnitude of said output RF signal via an envelope detector.
20. The method according to claim 19 , wherein said closed loop feedback comprises a real time-based control of said magnitude of said output RF signal.
21. The method according to claim 19 , comprising filtering said generated signal that is proportional to said magnitude of said output RF signal.
22. The method according to claim 19 , comprising generating a root-mean-squared (RMS) value of said generated signal that is proportional to said magnitude of said output RF signal.
23. The method according to claim 19 , comprising generating a real time error signal by subtracting said signal proportional to said magnitude of said output RF signal from a desired magnitude of said output RF signal.
24. The method according to claim 19 , wherein said envelope detector comprises a diode.
25. A system for processing signals, the system comprising:
one or more circuits for use in a wireless transmitter, wherein said one or more circuits comprise a power amplifier and a programmable gain amplifier, and said one or more circuits are operable to determine a magnitude of an output RF signal generated from said power amplifier;
said one or more circuits are operable to configure a gain of said PGA coupled to an input of said power amplifier via closed-loop feedback to maintain a desired magnitude of said output RF signal; and
said one or more circuits comprise an envelope detector, and wherein said one or more circuits are operable to generate a signal proportional to said magnitude of said output RF signal via an envelope detector.
26. The method according to claim 25 , wherein said closed loop feedback comprises real time-based control of said magnitude of said output RF signal.
27. The method according to claim 25 , wherein said one or more circuits are operable to filter said generated signal that is proportional to said magnitude of said output RF signal.
28. The method according to claim 25 , wherein said one or more circuits are operable to generate a root-mean-squared (RMS) value of said generated signal that is proportional to said magnitude of said output RF signal.
29. The method according to claim 25 , wherein said one or more circuits are operable to generate a real time error signal by subtracting said signal proportional to said magnitude of said output RF signal from a desired magnitude of said output RF signal.
30. The method according to claim 25 , wherein said envelope detector comprises a diode.