Digital Upconversion Architecture for Quadrature Modulators
نویسنده
چکیده
Traditionally, the digital implementation of modems is restricted to parts operating at baseband frequency. At higher frequencies , roughly 30 MHz and beyond, analog technologies such as SAW lters provide a better power/performance gure 1]. In this paper, we show how this barrier can be broken by trading programmability for speed. Using a digital multirate lter structure that ooers combined interpolation and frequency shifting, an area-and power eecient digital upconversion is achieved.
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