A W-band high-power predistorted direct-conversion digital modulator for transmitter applications

• Published in: IEEE microwave and wireless components letters Vol. 15; no. 9; pp. 600 - 602
• Main Authors: Hong-Yeh Chang, Jeng-Han Tsai, Tian-Wei Huang, Wang, Huei, Yongxiang Xia, Yonghui Shu
• Format: Journal Article
• Language: English
• Published: New York, NY IEEE 01.09.2005; Institute of Electrical and Electronics Engineers
• Subjects: Amplifiers; Applied sciences; Circuit properties; Digital modulation; Digital signal processing; Electric, optical and optoelectronic circuits; Electronic circuits; Electronic equipment and fabrication. Passive components, printed wiring boards, connectics; Electronics; Exact sciences and technology; Linearity; Linearization; millimeter-wave (MMW); Power amplifiers; Power generation; Predistortion; quadrature amplitude modulation (QAM); Quadrature phase shift keying; quadrature phase shift keying (QPSK); Radio frequency; Radio transmitters; Radiocommunications; Signal convertors; Telecommunications; Telecommunications and information theory; Transmitters. Receivers; W-band direct-conversion transmitter; Wireless LAN; Quadrature amplitude modulation; Output power; Transmitter; Microwave; Digital processing; millimeter-wave (MMW); Millimetric wave; quadrature phase shift keying (QPSK); W-band direct-conversion transmitter; Differential phase shift keying; Queue; Linearization; Modulator; Direct convertor; quadrature amplitude modulation (QAM); Power electronics; Adjacent channel; Quadrature phase shift keying; High power; Integrated circuit; W band; Signal processing; Power amplifier; Digital signal processor; Signal distortion
• ISSN: 1531-1309; 1558-1764
• DOI: 10.1109/LMWC.2005.855382

This letter presents a W-band high-power direct-conversion transmitter using digital predistortion techniques for digital modulation applications. The transmitter is a direct-conversion configuration that employs a reflection-type IQ modulator module and a power amplifier module. With the predistortion function in digital signal processing (DSP), this transmitter demonstrated an output channel power of greater than 19 dBm, and the adjacent channel power ratio (ACPR) was improved by 10 and 18 dB for QPSK and /spl pi//4-DQPSK modulation, respectively. To the best of our knowledge, this is the first demonstration of linearization techniques for W-band high-power digital modulation transmitters.