volume | PIER Journals

Abstract

We will demonstrate an alternative topology to greatly increase the operating bandwidth of an analog RF feedback power amplifier. A limited operating bandwidth due to the group delay mismatch of a feedback loop discouraged the use of an RF feedback technique in spite of its powerful linearization performance and great tolerance capability. By introducing a negative group delay circuit (NGDC) in the feedback loop, group delay match condition could be satisfied. With the fabricated 2-stage distributed element negative group delay circuit with a 30MHz of bandwidth and a -9 ns of group delay for a wideband code division multiple access (WCDMA) downlink band, the proposed feedback amplifier with the proposed topology experimentally achieved an adjacent channel leakage ratio of -53.2 dBc with a cancellation bandwidth of over 50 MHz.

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Dr. Heungjae Choi

Prof. Yongchae Jeong

Dr. Chul Dong Kim

Dr. James Stevenson Kenney