Highly Efficient HBT Power Amplifier Using High-Q Single- and Two-Winding Transformer With IMD3 Cancellation
- Resource Type
- Periodical
- Authors
- Ahn, H.; Oh, K.; Nam, I.; Lee, O.
- Source
- IEEE Access Access, IEEE. 9:85060-85070 2021
- Subject
- Aerospace
Bioengineering
Communication, Networking and Broadcast Technologies
Components, Circuits, Devices and Systems
Computing and Processing
Engineered Materials, Dielectrics and Plasmas
Engineering Profession
Fields, Waves and Electromagnetics
General Topics for Engineers
Geoscience
Nuclear Engineering
Photonics and Electrooptics
Power, Energy and Industry Applications
Robotics and Control Systems
Signal Processing and Analysis
Transportation
Power amplifiers
Power generation
Circuit faults
Windings
Heterojunction bipolar transistors
Impedance
Peak to average power ratio
InGaP/GaAs HBT power amplifier
IMD3 cancellation
single-winding transformer
PCB
femtocell
- Language
- ISSN
- 2169-3536
This paper presents a highly efficient InGaP/GaAs HBT power amplifier (PA) implemented using a proposed high- $Q$ single- and two-winding transformer. A single- and two-winding transformer is designed with a printed circuit board (PCB) to combine the output power with a reduced passive loss. Compared to a typical 1:2 two-winding transformer, an additional unit amplifier is connected at the mid-point of the secondary winding to construct a single-winding transformer without additional windings. An IMD3 cancellation technique using a single- and two-winding transformer is also proposed to obtain a high linear output power with high power-added efficiency (PAE) without additional design circuitry. The IMD3 components of the two input currents in the single- and two-winding transformer are 180° out-of-phase cancelling each other at output. The proposed PA is integrated with an InGaP/GaAs HBT process using a PCB transformer. The experimental results demonstrate that the PA achieves a saturated output power of 33.3 dBm, with a PAE of 61.3% at 0.91 GHz. The proposed PA is also tested with an orthogonal frequency-division multiplexing (OFDM) 64-quadrature amplitude modulation (QAM) signal having a bandwidth of 10 MHz and peak-to-average power ratio (PAPR) of 7.8 dB at 0.91 GHz to evaluate the improvement in linearity. The PA achieves an adjacent channel leakage ratio (ACLR) of −42 dBc up to an output power of 26.0 dBm with a PAE of 26.8% and current consumption of 297 mA.