Energy detection method based on weighting matrix filtering

Abstract

The invention discloses an energy detection method based on weighting matrix filtering. The energy detection method based on weighting matrix filtering comprises the steps that sampling is conducted on signals of a monitored frequency band, so that sampled signals are obtained; signals of all sampling points of the sampled signals are grouped, and each group of signals of the sampling points form a column vector; a weighting matrix used for filtering is obtained through the convex optimization technology according to the frequency range of a monitored channel needing spectrum sensing and the total number of the signals of the sampling points of each group; the energy of the monitored channel needing spectrum sensing is worked out through the weighting matrix and all the column vectors; through comparison between the energy of the monitored channel and a judgment threshold, whether an authorized user signal exists in the monitored channel or not is judged, and spectrum sensing is achieved. The energy detection method based on weighting matrix filtering has the advantages that according to the obtained weighting matrix, the energy of the monitored channel can be directly obtained; in addition, when the order of the weighting matrix used for filtering is equal to the order of an FIR filter, higher spectrum sensing performance can be obtained.

Description

technical field [0001] The invention relates to a spectrum sensing technology in a cognitive radio system, in particular to an energy detection method based on weighted matrix filtering. Background technique [0002] In the case of limited wireless spectrum resources, improving resource utilization is one of the important research directions of wireless communication. The measurement results of many countries such as China, the United States, the United Kingdom, Singapore, and Japan show that the resource utilization rate of the wireless spectrum in the existing wireless communication system is very unbalanced, and the resource utilization rate in space and time is between 15% and 85%. between. Under the existing wireless spectrum allocation policy, wireless communication systems have the exclusiveness of spectrum use, that is, each wireless spectrum resource can only be monopolized by one wireless communication system, even if these wireless spectrum resources are idle, ot...

AI Technical Summary

Problems solved by technology

However, when the order of the FIR filter is low, the frequency response characteristics of the FIR filter are poor, which will result in the inability to effectively filter out the signals of other monitoring channels in the monitoring frequency band. Part of the signal is also filtered out, which will reduce the performance of spectrum sensing

In order to improve the frequency response characteristics of the FIR filter, the order of the FIR filter must be increased, and increasing the order of the FIR filter will increase the computational complexity

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