【摘要】 模拟预失真是补偿行波管非线性失真的一种非常重要的方法。不过,目前大多数的预失真器需要在输入输出端加隔离器,增加了系统的复杂性。本文介绍一种工作在L波段的基于二极管的预失真线性化器。这种预失真线性化器利用3dB分支线耦合器的特性,实现输入输出端的良好匹配。随着输入功率的增加,该预失真线性化器可以达到不同的增益扩张和相位扩张。级联行波管后的测试表明,采用这种预失真线性化器,使得行波管在额定输入功率范围内的增益压缩和相位压缩从以前的6 dB和40°改善到0.5 dB和5°。更多还原

【Abstract】 A novel type of analog pre-distortion linearisier has been successfully developed and fabricated to compensate the non-linearity of the traveling wave tube amplifiers.The newly-developed pre-distortion lineariser,based on a Schottky diode,operates in L-band.The 3 dB 90° branch line coupler makes it possible for the lineariser to match perfectly the input and output ports.With an increase of the input power,different combinations of gain-expansion and phase-shift can be achieved over the dynamic range of input power.In the experimental tests,the AM-AM and the AM-PM characteristics of the TWT amplifier with the newly-developed pre-distortion lineariser were found to be improved from-6 dB and-40° to-0.5 dB and 5°.更多还原