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CoGnitive radio network for the smart Grid
DPO is set to 6.25 GS/ s. Recorded time domain Wi-Fi signals are
shown in Figure5.10. e duration of the recorded Wi-Fi signals
is 40 ms.
e recorded 40-ms Wi-Fi signals are divided into 8,000 slots,
with each slot lasting 5 μs. ese slots can be viewed as spectrum-
sensing slots. e time domain Wi-Fi signals within the first 1 μs of
every slot are then transformed into the frequency domain using the
fast Fourier transform (FFT), which is equivalent to FFT-based spec-
trum sensing. e frequency band of 2.411–2.433 GHz is considered.
e resolution in the frequency domain is 1 MHz. erefore, for each ...