Abstract
This paper presents a high-efficiency, high-bandwidth solution to implementing an envelope tracking power supply for the RF power amplifier (RFPA) in a Tetra2 base station. The solution is based on synchronous rectified buck topology, augmented with high-side switch zero-current switching (ZCS) implemented with a series inductor and an external clamping power supply. Combined with advanced power stage components (die-size MOSFETs), a high-performance fixed-frequency self-oscillating (sliding mode) control strategy and a 4th-order output filter, this leads to a compact, effective and efficient overall solution switching at 1MHz with 88-95% efficiency. In a class-AB RFPA amplifying a 50kHz bandwidth QAM Tetra2 signal at 4.6W average output power, the use of tracking supply voltage reduced power dissipation by 25W.
| Original language | English |
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| Title of host publication | INTELEC 2007 |
| Publication date | 2007 |
| Publication status | Published - 2007 |
| Event | INTELEC 2007 - Rome, Italy Duration: 1 Jan 2007 → … |
Conference
| Conference | INTELEC 2007 |
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| City | Rome, Italy |
| Period | 01/01/2007 → … |