摘要
提出了一种基于DDS的数字IQ调制的实现方法。该方法在利用FPGA实现DDS的基础上,通过运算电路对采用DDS技术产生的两路正交数字载波信号和存储在RAM中的信号星座图的各点的同相分量及正交分量进行处理,可以实现MPSK,MQAM等多进制数字调制。该方法中IQ调制的全部过程都用数字电路完成,极大地提高了IQ调制的抗干扰性和可重复性。重点对IQ映射功能做了详细的分析和设计,最后给出了实验验证和结论。
A realization method of digital IQ modulation based on DDS（direct digital frequency synthesizer） is presented.On the basis of design of DDS utilizing FPGA,by processing the two quadrature digital carrier signals generated by DDS technique and the In-phase value and the Quadrature value of the points of the signal constellations memorized in the RAM,this method is able to realize the multi-band digital modulation such as MPSK,MQAM,etc.The entire modulation process is done with digital circuitry,this method greatly improves the immunity,and repeatability of IQ modulation.IQ map is analyzed and designed in detail.The result of experiment and conclusion is presented.
出处
《电子测试》
2012年第1期19-22,共4页
Electronic Test
