A Spectrum Sensing Method Based on Multi-antenna Instantaneous Power Comparison

Abstract

The invention discloses a spectrum sensing method based on multi-antenna instantaneous power comparison. The method comprises: adopting multiple receiving antennas to receive time-domain-continuous radio-frequency signals; conducting down conversion and time-domain sampling of the time-domain-continuous radio-frequency signals, so as to obtain corresponding time-domain-discrete baseband signals; then calculating instantaneous power of time-domain sampling points at every time-domain sampling moment, among the time-domain-discrete baseband signals, and reassigning all the instantaneous power in the order from low instantaneous power to high instantaneous power; calculating test statistics; by comprising the test statistics with a judgment threshold, determining whether there is frequency band that is occupied by other radio communication services, thereby realizing spectrum sensing. The invention has the advantages that the performance of spectrum sensing is good, the defect is overcome that the energy detection method requires precise prediction of noise power, and the defect of the characteristic value detection method is also overcome that spectrum sensing fails under the condition of low or no time-domain correlation among signals received by the multiple antennas.

Description

technical field [0001] The 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 comparison. 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 (Cogniti...

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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