A multi-resolution spectrum sensing technique based on recursive discrete fourier transform for cognitive systems in tv white space

PURPOSE: A multiple spectrum sensing technique based on recursive discrete Fourier transform for recognizing TV white space communication system is provided to appropriately adjust a frequency resolution about each sensing a frequency component in a limited sensing frequency condition. CONSTITUTION: The frequency interval of a received signal is separated to a set frequency interval. A separated frequency interval is measured at a signal power. The size of a measured signal power at a frequency interval is determined a size that is less than an established threshold value. When the size of a measured signal power is less than the threshold value, a signal frequency interval is re-partitioned along with a measured size. A signal power is re-measured about a re-separated frequency interval.