WiMAX系统中频模块的设计与实现

Design and realization of intermediate frequency module in WiMAX system

在WiMAX系统中,由于从基带到射频一次变频实现难度及复杂度非常大,数字中频处理是其重要的组成部分,通过处理可以实现对射频信号的频谱搬移和速度转换,以保证数字信号处理芯片的及时处理,因此,数字中频技术对系统的实现起着重要作用。选择将频率搬移到中频的设计方案,按照设计要求采用自主选择的芯片完成中频功能,主要包括中频控制模块的实现、数字上下变频、中频波峰抑制、射频相关芯片寄存器设置和初始化工作,仿真和测试结果说明,该设计在性能满足设计要求的同时有着良好的应用前景。

In the WiMAX system, since it is difficult and complicated to realize single frequency conversion from baseband to radio frequency, the digital intermediate frequency processing module is an important part, through which the system can achieve frequency transfer and speed change of RF signal to make sure the processing of digital signal processing chip time- ly. So IF module plays an important role in the realization of the system. This paper chose to move it to the IF. In accord- ance with the design requirements, IF functions were completed by choosing chips. IF functions involving the realization of IF control module, digital up converter and digital down converter, IF peak suppression, setting and initialization the RF- related register. Simulation and testing suggest that the scheme satisfies the design requirements in performance and it has application prospects.