Wide/Multiband Linearization of TWTAs Using Predistortion

This paper discusses the state of the art in achieving wideband (>1 GHz) linearization of TWTAs. Multioctave bandwidth linearization has been achieved at frequencies from L- to Ka-band. The trades between using a single predistortion linearizer and multiband linearizers are discussed. The effect of harmonics (both even and odd-order-distortion products) and their correction for applications that cover more than an octave are considered.

I. Introduction

As a result of the application of new digital modulation techniques and the demand for the transmission of ever larger amounts of information, the need for efficient wideband linear power amplifiers has greatly increased. Possible applications include communications, radar, and electronic warfare. TWTAs remain the most efficient means of microwave and millimeter-wave high-power amplification [1]. With the addition of linearization, TWTAs can provide linear and wideband power amplification [2], [3].