| 摘要 |
The presence of an incumbent signal is detected in order to allow secondary users to share spectrum white space with incumbent users who have pre-emptive access to the spectrum. The spectrum is relinquished to the incumbent user to preclude any potential harmful interference and enable spectrum sharing. The presence of an incumbent signal (39) is detected by performing a frequency domain transformation on a received signal (51) to generate a plurality of frequency-domain components (53). A maximum frequency domain component is identified from among the plurality of frequency-domain components (53). The identified maximum frequency domain component is squared, and the result is compared to a detection threshold value to determine if the incumbent signal is present. |
