A Polar-Transmitter Architecture Using Multiphase Pulsewidth Modulation

作者：Chen Jau Horng^*; Yang Hao Shun; Lin Hou Chung; Chen Yi Jan Emery

来源：IEEE TRANSACTIONS ON CIRCUITS AND SYSTEMS I-REGULAR PAPERS, 2011, 58(2): 244-252.

DOI：10.1109/TCSI.2010.2071918

• Modulators
• power amplifiers (PAs)
• pulsewidth modulation (PWM)
• radio transmitters

This paper presents a transmitter architecture based on a pulse-modulated polar transmitter using multiphase pulsewidth modulation. The modulation to the radio-frequency input signal, instead of conventional drain modulation, significantly reduces the circuit complexity, while the multiphase modulation technique reduces the out-of-band emissions. An 836.5-MHz four-phase prototype transmitter using four class-C power amplifiers in parallel was constructed. Using the transmitter, single-phase, two-phase, and four-phase pulsewidth modulated signals were tested to verify the benefits of using the proposed multiphase architecture. Using a CDMA2000 1X signal, 46.8% efficiency at a 29-dBm output power level was measured while passing the spectral-mask requirements without using any kind of digital predistortion or calibration.

• 出版日期2011-2
• 单位中国科学院电工研究所