一种适用于时分系统中的DAC校准方法

在宽带通信系统中,IQ信号不平衡会导致直流分量,而由此产生的本振干扰会落到工作带内,严重影响系统性能。实际使用中需要调整DAC输出的IQ信号幅度和相位来逼近理想正交特性。传统的方法生产时逐个频点进行校准写表,生产时校准写表的时间很长。本文所述的方法利用基站上电完成之前的空闲时间,不需要在生产时进行DAC校准写表,大大提高了生产效率。

In broadband communication systems, IQ signal imbalance will cause the DC component, the resulting effect is that the local oscillator interference will fall into working frequency band, which seriously affects the system performance, In practical use, it need to adjust the amplitude and phase of IQ signal output from DAC （ Digital to Analog Converter ） to approach the ideal orthogonal property. The traditional method is to calibrate and write table for every frequency point in productive process, which costs for such a long time. The method proposed can complete the process of DAC calibration and write table using leisure time of waiting the finish of base station starting up, rather than wasting the productive time. The method proposed will greatly improve the production efficiency.