一种新的用于射频功率放大器的预失真法

改善射频功率放大器非线性的方法通常有功率回退法、负反馈法、前馈法和预失真法。预失真技术与其他线性化技术相比具有电路结构简单、性能优良、成本低等优点,因而受到设计者的青睐。设计了一种利用混频器和滤波器分别产生三阶和五阶交调分量的预失真器,采用复增益调节器控制预失真器产生的IMD3,IMD5幅度和相位。并从理论上对其特性进行了分析,利用专用的微波电路仿真工具进行仿真验证,仿真结果表明双音测试在2 GHz频段,IMD3和IMD5分别改善了17 dBc和12 dBc。

New Pre- distortion Method of RF Power Amplifier

To improve the non-linearization of RF power amplifier,power-backoff,negative-forward,feed-forward and pre-distortion method are used usually.Compared with these linearization techniques,pre-distortion technique provides simple circuit design,good performance and relative low cost.In this paper,a new predistortion linearizer is proposed,which uses mixer and filter to generate IMD3 and IMD5 independently and complex gain adjuster to control the amplitude and phase of IMD3 and IMD5.A computer emulated result is also provided.Two tones test show that the improvements in IMD3 and IMD5 cancellations are 17 dBc and 12 dBc respectively.