Alternative HF Conversion using an Image Spectrum of the D/A Converter

This paper describes a digital solution for high frequency up-conversion as an alternative to the traditional analog mixing. By this way, the complexity of the analog circuit is reduced. In order to accomplish this alternative frequency conversion, an image spectrum of the output baseband spectrum of the D/A converter is used so as to reconstruct the analog signal. In the digital domain an additional interpolation is needed for putting this method into practice due to the reason that the sampling frequency affects the position of the image spectra. Another factor which affects the desired position is the digital intermediate frequency conversion. The consequences of both factors will be discussed in this paper