Читать книгу Dynamic Spectrum Access Decisions - George F. Elmasry - Страница 43
2.6 Other Sensing Techniques
ОглавлениеThere are many other sensing techniques that have been proposed in the literature and are not detailed here, including the following:
Multitaper spectral estimation. This technique is widely used in neuroscience and other biomedical engineering applications. It estimates the power spectrum of the signal that is a stationary ergodic random process with finite variance (wideband signals can carry these characteristics). It detects contiguous realization of the signal and uses a maximum likelihood estimator to calculate the signal's power spectral density.
Random Hough transform. While most non time domain spectrum sensors use Fourier transform (FT), this approach proposes the use of a different transform domain for signal detection. The Hough transform domain suits signals with periodic patterns where it exploits the statistical covariance of noise and signal. This spectrum sensing technique can be effective at detecting digital television (DTV) signals.
Wavelet transform based estimation. This approach uses another transform domain. Wavelet18 domain is used for detecting edges in the power spectral density. These edges can result from the transition from the occupied band to the empty band and vice versa. Analog implementation of wavelet transform based sensing have the advantage of needing low power consumption and it can be implemented in real time.