Method and system of cognitive radio spectrum sensing based on Gabor algorithm

Abstract

The invention provides a method and a system of cognitive radio spectrum sensing based on a Gabor algorithm. The method of the cognitive radio spectrum sensing based on the Gabor algorithm comprises the following steps: step 101: sensing the conduction of sampling processing of detected continuous signals received by a user through the Gabor algorithm to obtain a discrete-time signal; step 102: calculating the Gabor coefficient of the discrete-time signal and obtaining the module value of the Gabor coefficient to be used as the energy of the detected signal; step 103: if the module value of the obtained Gabor coefficient is larger than a pre-set judging threshold, judging that a main user exists in the detected frequency range; if the module value of the obtained Gabor coefficient is smaller than the pre-set judging threshold, judging that no main user exists in the detected frequency range. When the Shannon principle is adopted for sampling, the Gabor algorithm is combined, and the sampling adopting the Gabor algorithm needs to meet that TOmega<=2pi or MN<=N1, T is a time sampling period and Omega is a frequency sampling period. On the basis of traditional energy detection, the Gabor algorithm is imported for improving the detection accuracy of the main user, , the method of the cognitive radio spectrum sensing based on the Gabor algorithm can effectively improve the accuracy of a detection result especially in low signal to noise ratio.

Description

technical field [0001] The present invention relates to a cognitive radio spectrum sensing method, in particular to a fast and accurate Gabor algorithm-based cognitive radio spectrum sensing technology, that is, the present invention provides a Gabor algorithm-based cognitive radio spectrum sensing method and system. Background technique [0002] In cognitive radio systems, spectrum sensing is the most important and the first technical problem to overcome. Only when effective spectrum sensing is carried out, can dynamic allocation of spectrum and application of spectrum management be carried out based on the results of spectrum sensing, and will also provide a basis for the flexible and intelligent work of cognitive radio. [0003] The current communication technology service model has shifted to broadband services such as video, audio and high-definition pictures, and the lack of wireless spectrum resources has become one of the bottlenecks in the promotion of high-perform...

AI Technical Summary

Problems solved by technology

The spectrum detection algorithm used in the prior art includes: matched filter detection method, energy detection method, etc., the flow chart of the energy detection algorithm is as follows figure 1 As shown, because the energy detection algorithm of the prior art is simple to implement and has a wide range of implementation, the present invention is based on the energy detection algorithm, but the existing energy detection algorithm has the following defects: ① cannot provide stable and reliable Detection performance

For example, when the signal-to-noise ratio is greater than -20dB, a certain detection probability can still be maintained, but when it is lower than -20dB, the actual detection becomes more and more difficult. At -23dB, no matter how long the sensing time is, it is basically impossible detected signal

This situation stems from the fact that the power of the noise in the actual system cannot be accurately determined, and the power of the noise changes with time. If the preset threshold is set too high, the signal cannot be detected; if the preset threshold is set too low, the error The probability will increase again

②When the noise power is too large, the energy detection cannot distinguish between the modulation signal and the noise

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