Design of a 4-W Envelope Tracking Power Amplifier With More Than One Octave Carrier Bandwidth

作者：Yan Jonmei J^*; Hsia Chin; Kimball Donald F; A**eck Peter M

来源：IEEE Journal of Solid-State Circuits, 2012, 47(10): 2298-2308.

DOI：10.1109/JSSC.2012.2204927

• Base station
• broadband
• dynamic supply modulator
• efficiency
• envelope tracking
• gallium nitride (GaN)
• integrated circuit
• power amplifier (PA)
• WCDMA

This paper presents a high-efficiency broadband envelope-tracking power amplifier with operation at carrier frequencies from 500 to 1750 MHz. The RF power amplifier (RFPA) is provided by a single-chip gallium-nitride (GaN) integrated circuit (IC) whose design included a broadband output match achieved by operating directly into a load resistance of 50 and broadband inputmatch achieved using a feedback network. Under single-tone excitation, the Class-AB GaN PA IC provides output power above 12Wwith greater than 50% drain efficiency and more than 10-dB gain at 40-V drain bias. When placed in envelope tracking configuration, using a representative WCDMA modulated signal with 4-MHz bandwidth and 6.6-dB peak-to-average power ratio, the ET PA achieved 4W of average output power at its peak average drain efficiency of 31% at 752 MHz (including the power dissipation of the envelope modulator). The RFPA individually was measured to have an average drain efficiency of 58.5% for the WCDMA signal. Across the 500-1750-MHz band, using the WCDMA signal, greater than 25% average drain efficiency with more than 10 dB of gain was measured.

• 出版日期2012-10