A 2.14-GHz Chireix outphasing transmitter

• Published in: IEEE transactions on microwave theory and techniques Vol. 53; no. 6; pp. 2129 - 2138
• Main Authors: Hakala, I., Choi, D.K., Gharavi, L., Kajakine, N., Koskela, J., Kaunisto, R.
• Format: Journal Article Conference Proceeding
• Language: English
• Published: New York, NY IEEE 01.06.2005; Institute of Electrical and Electronics Engineers; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: Amplification; Applied sciences; Channels; Circuit properties; Circuits; Design engineering; Downlink; Electric, optical and optoelectronic circuits; Electronics; Exact sciences and technology; High efficiency; High power amplifiers; Linearity; Microwave circuits, microwave integrated circuits, microwave transmission lines, submillimeter wave circuits; Microwaves; Multiaccess communication; outphasing; Phase modulation; Phases; PHEMTs; Power measurement; Quadratures; Radiocommunications; RF power amplifiers (PAs); Telecommunications; Telecommunications and information theory; Transmitters; Transmitters. Receivers; Waveforms; Wideband; Circuit design; transmitters; Wireless telecommunication; Microwave transmitter; Downlink; RF power amplifiers (PAs); outphasing; High electron mobility transistor; Power combiners; Wide band; High efficiency; Code division multiple access; Circuit realization; Pseudomorphic transistor; Power amplifier
• ISSN: 0018-9480; 1557-9670
• DOI: 10.1109/TMTT.2005.848770

A Chireix outphasing system for 2.14 GHz including two saturated class-B pseudomorphic high electron-mobility transistor power amplifiers (PAs) and a Chireix power-combining circuit is reported in this paper. In an outphasing system, an arbitrary input signal is divided into two constant envelope branches. The phase-only modulated branches are then amplified with high-efficiency nonlinear PAs. By controlling the phases of these branches, the original signal waveform can be reconstructed, ideally with high efficiency and perfect linearity. In this paper, the design and implementation of an experimental Chireix outphasing system for a wide-band code division multiple access 2.11-2.17-GHz downlink band is presented. The measured system efficiency for 7-dB backed-off quadrature phase-shift keying signal was 42.2% with a channel power of 31.2 dBm.