Thu, 21 Aug 2008 01:21:30 BST CiteULike: hoverste's Lanfranco http://www.citeulike.org/user/hoverste/author/Lanfranco CiteULike.org en-gb Copyright © 2004-2008 citeulike.org http://www.citeulike.org/user/hoverste/article/2755114 <i>Compound Semiconductor Integrated Circuit Symposium, 2005. CSIC '05. IEEE (2005), 4 pp..</i><br /><br />A high performance GaN HFET WCDMA basestation power amplifier is presented, which uses an envelope tracking bias system to achieve high linearity and efficiency. The measured overall power-added efficiency (PAE) reached 50.7%, with a normalized power RMS error of 0.7% and ACLR of -52dBc at an offset frequency of 5MHz, at an average output power of 37.2W and gain of 10.0dB for a single carrier WCDMA signal. To the authors' knowledge, this corresponds to the best efficiency reported for a single stage base station power amplifier. Digital predistortion (DPD) was used at two levels: memoryless DPD to compensate for the expected gain variation of the amplifier over the bias envelope trajectory, and deterministic memory mitigation, to further improve the linearity. The signal envelope had a peak-to-average power ratio of 7.67dB. 50% PAE WCDMA basestation amplifier implemented with GaN HFETs D Kimball P Draxler J Jeong C Hsia S Lanfranco W Nagy K Linthicum L Larson P Asbeck P Asbeck doi:10.1109/CSICS.2005.1531768 Compound Semiconductor Integrated Circuit Symposium, 2005. CSIC '05. IEEE (2005), 4 pp.. 2008-05-05T04:27:51-00:00 2005 Compound Semiconductor Integrated Circuit Symposium, 2005. CSIC '05. IEEE 4 pp. basestation dpd envelope et gan memory tracking wcdma http://www.citeulike.org/user/hoverste/article/2754999 <i>Microwave Symposium Digest, 2006. IEEE MTT-S International (2006), pp. 1534-1537.</i><br /><br />A high performance W-CDMA base station power amplifier is presented, which uses an envelope tracking bias system along with an advanced 0.4mum gate length LDMOS transistor, to achieve high efficiency. High linearity is also achieved by employing digital predistortion. For a target WCDMA envelope with a peak-to-average power ratio of 7.6 dB, the measured overall power-added efficiency (PAE) is as high as 40.4 %. Within this system, the RF power amplifier has an average drain efficiency of approximately 64%, and the envelope amplifier has about 60% efficiency. After the memoryless digital predistortion the normalized power RMS error is 3.3%, at an average output power of 27 W and gain of 14.9 dB. After memory mitigation the normalized power RMS error drops to below 1.0%. The efficiency ranks among the highest reported for a single stage LDMOS W-CDMA base station amplifier High Efficiency Envelope Tracking LDMOS Power Amplifier for W-CDMA P Draxler S Lanfranco D Kimball C Hsia J Jeong J van de Sluis PM Asbeck doi:10.1109/MWSYM.2006.249605 Microwave Symposium Digest, 2006. IEEE MTT-S International (2006), pp. 1534-1537. 2008-05-05T03:19:30-00:00 2006 Microwave Symposium Digest, 2006. IEEE MTT-S International 1534 1537 asbeck dpd draxler envelope kimball ldmos tracking wcdma