Design of Highly Efficient Wideband RF Polar Transmitters Using the Envelope-Tracking Technique

作者：Lopez Jerry^*; Li Yan; Popp Jeremy D; Lie Donald Y C; Chuang Chia Chang; Chen Kevin; Wu Stanley; Yang Tzu Yin; Ma Gin Kou

来源：IEEE Journal of Solid-State Circuits, 2009, 44(9): 2276-2294.

DOI：10.1109/JSSC.2009.2022669

• DC-DC converter
• envelope amplifier
• envelope-elimination-and-restoration (EER)
• envelope-tracking (ET)
• monolithic RF SiGe power amplifier (PA)
• polar transmitters
• power-added efficiency (PAE)
• radio-frequency (RF)
• switch-mode PA
• system-on-a-chip (SoC)
• wideband transmitter

This paper discusses the design issues of highly efficient and monolithic wideband RF polar transmitters, especially the ones that use the envelope-tracking (ET) technique. Besides first reviewing the current state-of-the-art polar transmitters in the literature, three focus topics will be discussed: 1) the system-on-a-chip (SoC) design considerations of the monolithic polar transmitter using ET versus EER (envelope elimination and restoration); 2) the design of highly efficient envelope amplifier capable of achieving the high efficiency, current, bandwidth, accuracy and noise specifications required for wideband signals; and 3) the design of high-efficiency monolithic Si-based class E power amplifiers (PAs) suitable for ET-based RF polar transmitters. A design prototype of a polar transmitter using ET and a monolithic SiGe PA that passed the stringent low-band EDGE (Enhanced Data rates for GSM Evolution) transmit mask with 45% overall transmitter system efficiency will be given; the simulated data of the entire polar transmitter system is also compared against the measurement. Further investigations on how to solve the technical challenges to successfully implement linear and high-efficiency ET-based polar transmitter for broadband wireless applications such as WiBro/WiMAX are also discussed.

• 出版日期2009-9