| 摘要 |
A blind spectrum sensing method and device based on fast Fourier transform. The method comprises: the spectrum sensing device receives a signal on an authorized spectrum band, calculates an autocorrelation coefficient of the received signal after sampling and filtering same, then performs a fast Fourier transform of the autocorrelation coefficient, acquires the modulus of the transform result, constructs determination variables on the basis of the modulus, and determine whether or not a signal of an authorized user is present. The method and device have the advantages of low calculation complexity, obviated need for authorization information characteristic, and insensitivity towards noise uncertainty, and are of great performance. |
| 主权项 |
1. A blind spectrum sensing method based on fast Fourier transform comprising:
receiving a wireless signal on a frequency band to be sensed; after sampling and filtering the received wireless signal, calculating the autocorrelation coefficient of the sampled and filtered wireless signal; performing fast Fourier transform of the autocorrelation coefficient on M point, and performing spectrum sensing according to the result of fast Fourier transform; performing modular operation on the result of fast Fourier transform, recording the module values as f1,f2, . . . ,fM, and constructing numerical values T1 and T2 according to the module values, wherein T1 and T2 both are multivariate functions of f1,f2, . . . ,fM, which at least includes one of the f1,f2, . . . ,fM, respectively; and calculating a judgment variable T=T1T2, when T is greater than the preset judgment threshold, judging that an authorized signal exists on the spectrum, and when T is less than the preset judgment threshold, judging that no authorized signal exists. |
