07570931 is referenced by 22 patents and cites 33 patents.

An RF transmitter (30) includes an RF power amplifier (32) for which the power input bias voltage (40) and signal input bias voltage (80) are controlled within feedback loops. A peak detector (44) generates a lowered-spectrum, peak-tracking signal (34) that follows the largest amplitude peaks of a wide bandwidth communication signal (16) but exhibits a lower bandwidth. This signal (34) is scaled in response to the operation of a drain bias tracking loop (146) then used to control a switching power supply (36) that generates the power input bias voltage. The tracking loop (146) is responsive to out-of-band power detected in a portion of the amplified RF communication signal (16″). A ratio of out-of-band power (128) to in-band power (126) is manipulated in the tracking loop (146) so that the power input bias voltage is modulated in a way that holds the out-of-band power at a desired predetermined level.

Title
RF transmitter with variably biased RF power amplifier and method therefor
Application Number
11/445816
Publication Number
7570931 (B2)
Application Date
June 2, 2006
Publication Date
August 4, 2009
Inventor
Eric M Brombaugh
Mesa
AZ, US
Ronald Duane McCallister
Scottsdale
AZ, US
Agent
Charlene R Jacobsen
Jordan M Meschkow
Lowell W Gresham
Assignee
Crestcom
AZ, US
IPC
H04B 1/04
H01Q 11/12
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