BI-DAC System with Guard Band: Trade-off between Bandwidth and Aliasing Suppression

BI-DAC(Bandwidth Interleaving DAC) has shown great application potential in breaking through DAC bandwidth restriction. Aliasing error is one of the main errors in BI-DAC. This kind of error can be effectively eliminated by setting guard band. Considering the attenuation of filter transition band, there is a trade-off between the width of guard band and the suppression of aliasing. In this paper, the relationship between guard band and the transition band of analog filter is analyzed, and the expression of the relationship under the given aliasing suppression is proposed. Simulation results show that 50dB aliasing suppression can be achieved at the cost of 31 % bandwidth improvement.