| The WCDMA system, with the multi-carrier and multi-level, requires high linearity of power amplifier. The linearity technologies can be classified into three classes. This paper deals with the digital baseband predistortion technology.Low efficiency and poor adaptive ability are the main problems of the traditional predistortion algorithm in improving the linearity of power amplifier, especially in WCDMA system where peak-to-average power ratio is high. Firstly, we discussed how the nonlinearity affects the transmission of the WCDMA signals, illustrating the effects of the nonlinearity to the signal amplitude, the signal phase, the power spectrum density and the bits error ratio. Secondly, compared the radio predistortion and DLP technology. Finally, we discussed some key details in implementing the DLP module and the hardware framework. The results of floating-point test and fixing-point test both verify the validity and practicability of this algorithm. |
PDF Full Text Request