Power Control Scheme For A Power Amplifier

Abstract

In one embodiment, a method includes detecting a power level of a power amplifier coupled to a transceiver during a current burst of a radio communication and providing the detected power level from the power amplifier to the transceiver and controlling a power level of the power amplifier during a next burst based on the detected power level of the current burst.

1 . A method comprising:
 receiving, during a first mode of operation, a detected power level of a power amplifier in a transceiver coupled to the power amplifier via a feedback path coupled between the power amplifier and the transceiver;   calculating, in the transceiver, a power level of the power amplifier based on the detected power level, and controlling a power output of a radio frequency (RF) signal provided by the transceiver to the power amplifier based on the calculation; and   receiving, during a second mode of operation, the detected power level in a controller of the power amplifier and controlling transmit power from the power amplifier based thereon.   
     
     
         2 . The method of  claim 1 , further comprising determining a correction value for a variable gain amplifier of the transceiver based on the detected power level. 
     
     
         3 . The method of  claim 2 , further comprising determining a control value for the variable gain amplifier based on the correction value, a previous correction value, a threshold level for the detected power level, and a correction value limit. 
     
     
         4 . The method of  claim 3 , further comprising determining the correction value based on a sum of:
 a function of a difference between the detected power level and the threshold level; and   the previous correction value.   
     
     
         5 . The method of  claim 3 , further comprising receiving the threshold level and the correction value limit from a baseband processor coupled to the transceiver. 
     
     
         6 . The method of  claim 1 , further comprising detecting the power level during transmission of a training sequence of a current burst. 
     
     
         7 . The method of  claim 6 , wherein the training sequence is present in a midamble portion of the current burst. 
     
     
         8 . A transceiver comprising:
 an interface to receive transmit power control information from a baseband processor;   a controller coupled to the interface to receive the transmit power control information and to determine parameter information for a first burst of a data transmission based on the transmit power control information, wherein the controller is to receive, in a first mode of operation, power sample information from a power amplifier coupled to the transceiver and determine the parameter information further based on the received power sample information to control transmit power of the power amplifier;   circuitry to receive a baseband signal from the baseband processor, modulate the baseband signal, upconvert the modulated baseband signal to an intermediate frequency (IF) signal, and upconvert the IF signal to a radio frequency (RF) signal; and   a controllable amplifier controlled by the parameter information to output the RF signal from the transceiver to the power amplifier at a desired power level, wherein in a second mode of operation, the power amplifier is to the control the transmit power.   
     
     
         9 . The transceiver of  claim 8 , wherein the controller is to sample the power sample information from the power amplifier during a midamble portion of a burst. 
     
     
         10 . The transceiver of  claim 8 , wherein the transceiver is to operate in a closed-loop mode if the power sample information is present, otherwise the transceiver to operate in an open-loop mode. 
     
     
         11 . The transceiver of  claim 8 , wherein the controllable amplifier comprises a digital variable gain amplifier (DVGA). 
     
     
         12 . The transceiver of  claim 11 , wherein the transmit power control information comprises a threshold level for the power amplifier and a maximum correction value. 
     
     
         13 . An article comprising a machine-readable medium including instructions that enable a system to:
 receive, in a first mode of operation, a detected power level of a first communication burst from a power amplifier (PA) in a transceiver coupled to the PA via a feedback path coupled between the PA and the transceiver;   determine, in the transceiver, a power level update for a second communication burst based at least in part on the detected power level of the first communication burst;   provide the second communication burst to the PA from the transceiver responsive to the power level update in the first mode of operation; and   receive, during a second mode of operation, a detected power level of a third communication blast in a controller of the power amplifier and control transmit power from the power amplifier based thereon.   
     
     
         14 . The article of  claim 13 , wherein the instructions further enable the system to receive transmit power control information from a baseband processor coupled to the transceiver, the transmit power control information including a nominal power level. 
     
     
         15 . The article of  claim 13 , wherein the instructions further enable the system to compare, in the transceiver, the transmit power control information to the detected power level of the first communication burst and determine the power level update based at least in part on the comparison. 
     
     
         16 . The article of  claim 14 , wherein the instructions further enable the system to limit the power level update to a predetermined maximum, wherein the predetermined maximum is received from the baseband processor. 
     
     
         17 . The article of  claim 13 , wherein the instructions further enable the system to control a digital variable gain amplifier (DVGA) of the transceiver to generate the second communication burst based on the power level update. 
     
     
         18 . The article of  claim 13 , wherein the instructions further enable the system to sample the detected power level of the first communication burst during a training sequence.