This work presents a novel power amplifier (PA) architecture employing a feedforward-like loop structure for the linearization of a load-modulated PA. The load-modulating loop combiner (LMLC) is related to a feedforward amplifier, but with the interaction between the main and auxiliary amplifiers to generate both distortion cancellation and load modulation. A brief overview of the underlying theory is presented, followed by a hardware demonstrator operating at 3.5 GHz with 42-dBm peak output power and 55% peak drain efficiency in CW. When excited by a 100-MHz LTE signal, it maintains a 3-ppt EVM improvement and a 2–5-ppt average drain efficiency improvement compared to its standalone main amplifier.
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An inter-stage filter network for distortion reduction in concurrent dual-band power amplifier operation
This work presents a novel approach for reducing the out-of-band distortion generated in a concurrent dualband power amplifier (PA) without penalty to output power or efficiency using a filter between a driver amplifier and final-stage PA that manipulates the driver amplifier out-of-band distortion such that the overall distortion of the cascade is minimized. The cascaded PA operates at 2.4-GHz and 3.5-GHz with peak output power and drain efficiency of 41.6/40.4 and 65.2/55.1 respectively. The filter reduces the out-of-band distortion of the cascade when excited by dual 10-MHz LTE-like signals by 10 dB while improving average drain efficiency by 5 percentage points.
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- Award ID(s):
- 1846507
- PAR ID:
- 10386687
- Date Published:
- Journal Name:
- IEEE Asia Pacific Microwave Conference
- Page Range / eLocation ID:
- 1-3
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Accepted Manuscript1.0
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