Patent ID: 7136113

Claim:
A digital television receiver comprising: an antenna receiving channel signals of digital television broadcasting and having a directionality dependent on a control signal; a signal processing part tuning a wanted channel signal from the channel signals and processing the tuned channel signal as a wanted form; a detection part detecting state signals of the channel signal outputted from the signal processing part, wherein the state signals include a power of the channel signal, a power of a ghost signal, and a signal vs. noise ratio; a memory, when every new state signal is detected, storing a detected new state signal sorted with previously-detected state signals; a control part producing the control signal corresponding to an optimal direction of the antenna by comparing the new state signal to the previous state signals; and an interface part providing the antenna with the control signal, wherein the control part comprises: a signal power tracker tracking the power of the tuned channel signal using an output signal of a signal power detector; a ghost power tracker tracking the power of the ghost signal using an output signal of a ghost power detector; a signal vs. noise ratio (SNR) tracker tracking the signal vs. noise ratio using an output of a signal vs. noise ratio calculator; a tracking processor tracking states of the tuned channel signal using output signals of the trackers in a presently-selected antenna pattern and then changing the antenna pattern in order stored in the memory if the tracked states fail to maintain effective value sizes; a scan processor attaining an effective signal power and antenna pattern by varying the directionality of the antenna using an output signal of the tracking processor and then storing the power and pattern values in the memory; and a sort processor aligning the stored antenna pattern values in order of the signal power values.