Cooperative frequency spectrum sensing method for cognitive radio network

Abstract

The invention discloses a cooperative frequency spectrum sensing method for a cognitive radio network. The method comprises the following steps that: (1) the cognitive radio network which comprises N cognitive users SU and an information fusion center FC is configured in a network with an existing privileged user PU; (2) the cognitive user SU uses energy detection to independently judge whether aprivileged user PU signal is present, and transmits a binary hard decision result to the information fusion center FC, and the transmitting power of the cognitive user is adaptively adjusted according to the condition of a channel from the privileged user PU to the cognitive user SU; and (3) the information fusion center FC fuses the results of a plurality of cognitive users SU by adopting a maximum likelihood detector, and finally determines whether the privileged user PU is occupying the frequency spectrum. The cognitive user SU can independently process the signal without transmitting softinformation or interchanging information; and a detector in the information fusion center FC has a simple structure and is easy to implement. Meanwhile, the cooperative frequency spectrum sensing method has good performance such as low communication overhead, high diversity gain, low false alarm rate and lost detection rate and the like, and has high practical value.

Description

Technical field: [0001] The invention belongs to the field of communications, and relates to a spectrum sensing method, in particular to a spectrum sensing method for a cognitive radio network, and in particular to a collaborative technology-based spectrum sensing and its signal transmission and processing method. Background technique: [0002] With the rapid development of wireless communication services, existing networks are facing a contradiction between the scarcity of wireless spectrum resources and the increasing demand for spectrum resources by various services. Cognitive Radio (CR) uses the temporarily unused frequency band allocated to authorized users (Primary User, authorized user PU), that is, spectrum holes, to assist cognitive users (also known as secondary users, Secondary User , SU) transmits information, which opens up a new way to improve spectrum utilization, and has become a research hotspot in recent years, and it is also a key technology of the relevan...

AI Technical Summary

Problems solved by technology

However, the existing cooperative sensing technology lacks the research on fading channels and ignores the evaluation of diversity performance. The performance is not significantly improved; some methods require all cognitive users SU to transmit soft detection information to the fusion center (Fusion Center, information fusion center FC), which greatly increases the communication overhead in the distributed context

Especially for the case where the entire network is exposed to fading channels, the existing cooperative sensing technology either loses the diversity gain, or needs to make assumptions about the channel between the cognitive user SU and the information fusion center FC that cannot be established in the real environment

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