Direct digital-to-RF digital-to-analogue converter using image replica and nonlinearity cancelling architecture

A parallel architecture for a direct digital-to-RF digital-to-analogue converter (DDRF-DAC) is proposed for digital radio transmitters. Multiple paths of wide-bandwidth DACs are used, each fed with interleaved signal samples and each sampled at interleaved time instants. This results in the cancellation of the first N-1 replica images and the first N-1 nonlinearity spurs, thus allowing for wideband operation.