Frequency spectrum sensing method based on multi-antenna instantaneous power

Abstract

The invention discloses a frequency spectrum sensing method based on multi-antenna instantaneous power. According to the method, multiple antennas are utilized to receive continuous time domain radio-frequency signals; downconversion and time domain sampling are performed on each continuous time domain radio-frequency signal then, and then discrete time domain baseband signals are obtained; values of instantaneous power of time domain sampling points in each discrete time domain baseband signal at each time domain sampling time are then calculated; test statistics are calculated by using ranking and deassign results of instantaneous power of the multiple time domain sampling points at the same time domain sampling time and ranking and deassign results of power difference values between the maximum value of the instantaneous power and the minimum value of the instantaneous power; and, finally through comparison of the test statistics with a judgment threshold, whether other wireless communication services occupy a frequency band is determined, and frequency spectrum sensing is achieved. The method has the advantage of good frequency spectrum sensing performance, overcomes the defect that an energy detection method needs to know noise power, and also overcomes the defect that a characteristic value detection value has low correlation between the received signals or poor frequency spectrum sensing performance while the received signals are uncorrelated.

Description

technical field [0001] The present invention relates to a spectrum sensing technology in a cognitive radio system, in particular to a spectrum sensing method based on multi-antenna instantaneous power. Background technique [0002] With the rapid growth of wireless communication services, people's demand for spectrum resources continues to increase, and the phenomenon of lack of spectrum resources becomes more and more serious. On the one hand, the rapid development of wireless communication services and the continuous emergence of various systems, protocols, and networks have made more people need to use radio spectrum; on the other hand, many frequency bands have been allocated to authorized users, and non-authorized users can only use Those unlicensed frequency bands are very scarce, and the low utilization rate of spectrum resources in the existing fixed spectrum resource allocation strategy is one of the main reasons for this phenomenon. The cognitive radio (Cognitive ...

AI Technical Summary

Problems solved by technology

Spectrum sensing performance of energy detection and cyclic feature detection degrades severely when the noise power and the cyclic frequency of the licensed user signal are not known

In the case of multiple antennas, the covariance matrix detection method and the eigenvalue detection method can use the correlation between the received signals to realize spectrum sensing, but in practical applications, in order to obtain diversity gain, the correlation between the received signals is relatively low. Low or even irrelevant, at this time the spectrum sensing performance of the two methods is poor

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