Low Power Structure Digital Up Converter Design for Software Radio System

Abstract

The numerically controlled oscillator is often supposed to operate after interpolation in a conventional digital up converter, but such a converter works at quite high frequencies and consumes more power. In this paper, a type of low power structure digital up converter is proposed which carries out mixing and interpolating gradually, where the numerically controlled oscillator and the interpolation filter can both work at a lower frequency. Low power structure can move signal to any position within the whole Nyquist Band. Furthermore, the interpolation filter adopts a half-band filter with the structure of two parallel branches, which combines the functions of stuffing zero, filtering and modulation, and makes programmable modulation by exchanging input paths. A simulation is carried out on the Xilinx KC705 development kit, which indicates that its maximum work frequency of the low power structure reaches 392[Formula: see text]MHz while its power consumption reduces by 33.3% compared to the conventional structure.