This work presents the architecture of ATSC Terrestrial/Cable tuner which is highly competitive in the tuner market. Among the various receiver architectures, double conversion zero-IF architecture is an optimum solution for low cost and high performance.
In addition, this work is focused on designing a highly linear up-conversion mixer which is one of the important issues in designing double conversion zero-IF Digital TV tuner IC. After choosing the Micromixer among various kinds of mixers, by analyzing $g_m^"$ of the transconductor of Micromixer, a highly linear transconductor is proposed. In the conclusion, a highly linear CMOS up-conversion Micromixer using this transconductor is proposed.