Quantum mechanics

Parasitic capacitance

Voltage

Engineering

Capacitance

Materials science

Bipolar junction transistor

Power (physics)

Amplifier

Transistor

Physics

Adjacent channel

Heterojunction bipolar transistor

Electronic engineering

Handset

Electrode

CMOS

Optoelectronics

Electrical engineering

IEEE Microwave and Wireless Components Letters

A highly efficient fully integrated 5.15- to 5.85-GHz GaAs HBT differential power amplifier (PA) is implemented for long-term evolution (LTE) handset applications considering LTE licensed-assisted access. A simple and practical output network, based on an on-chip transformer, is proposed to achieve low loss. A neutralization technique to mitigate the parasitic base-collector capacitance is also adopted to improve PA performances. The implemented PA achieved a high gain of 26.6-28.1 dB and saturated power of 30.5-31.1 dBm with a high peak power-added efficiency of 40.4%-44.5% under a continuous-wave signal test across 5.15-5.85 GHz. When tested with 20- and 40-MHz bandwidth quadrature phase-shift keying LTE signals, the PA showed an adjacent channel leakage ratio of -33 dBc up to output powers of 24.1-24.4 and 22.2-22.8 dBm, respectively.

Highly Efficient 5.15- to 5.85-GHz Neutralized HBT Power Amplifier for LTE Applications