Disclosed herein are power amplification systems that are dynamically biased based on a
signal indicative of an envelope of the signal being amplified. The power amplifi cation …

US7570931B2 - RF transmitter with variably biased RF power amplifier and method therefor -
Google Patents US7570931B2 - RF transmitter with variably biased RF power amplifier and …

(*) Notice: Subject to any disclaimer, the term of this EP 1750 366 A2 2/2007 patent is
extended or adjusted under 35 EP 1750 366 A3 2/2007 USC 154 (b) by 51 …

Apparatus and methods for envelope tracking systems are provided. In certain
configurations, an envelope tracking system includes a digital filter that generates a filtered …

6.738. 432 B2 5, 2004 Pehlke et al.................. 375,300 2012fO252382 A1 10, 2012 Bashir et
al. 6,788.151 B2 9, 2004 Shvarts et al. 2012/0256686 A1 10/2012 Royer 6.799, 020 B1 …

Described embodiments provide a radio frequency (RF) amplifier system having at least one
amplifier. The at least one amplifier includes an RF input port, an RF output port and a drain …

Apparatus and methods for envelope tracking are disclosed. In one embodiment, a power
amplifier system including a power amplifier and an envelope tracker is provided. The power …

US9160287B2 - Linearization circuits and methods for multilevel power amplifier systems -
Google Patents US9160287B2 - Linearization circuits and methods for multilevel power amplifier …

Apparatus and methods for envelope tracking systems are provided. In certain
configurations, an envelope tracking system includes a digital filter that generates a filtered …

(51) Int. Cl.(57) ABSTRACT HO3G 3/20(2006.01) HO3F 3/93(2006.01) Circuits and methods
for performing multilevel power ampli HO3F L/32(2006.01) fication using multiple different …