Design of Digital Up-conversion Based on Inverse-sinc Compensation Algorithm

In digital up-conversion (DUC) systems, the ringing effect that occurs in the high-frequency band of the Cascade integral Comb (CIC) module and the inherent fading in the amplitude-to-frequency characteristics of the digital-to-analog converter (DAC) module lead to a high error rate during signal transmission. In this paper, we address this problem by improving the CIC filter module and DAC module using a combination of Inverse-sinc based digital compensation algorithm and optimized hardware structure. In the algorithm, a digital compensation algorithm based on Inverse-sinc algorithm is proposed to solve the amplitude distortion problem of the two modules by the method of inverse compensation, which reduces the dynamic error. For hardware design, a symmetric parallel structure is used to design the DAC module, which reduces the consumption of multiplier resources by 50%. Finally, through verification platform testing and comparative experimental analysis, the optimized scheme has an in-band flatness of basically 0, which improves the overall system computing speed while reducing hardware resource consumption.