Method and device for sensing graded frequency spectra in cognitive radio network

Abstract

The invention relates to a method and device for sensing graded frequency spectra in a cognitive radio network, belonging to the field of communication technology. In order to ensure the throughput of a cognitive radio network system and improve the service experience of a cognitive user under the condition that a master user is not disturbed or only disturbed slightly, the method for sensing graded frequency spectra, which is provided by the invention, uses special subframe time slots for uplink and downlink conversion in the frame structure of a time division system to sense a low-grade frequency spectrum, and after the sensing result of the low-grade frequency spectrum is analyzed, a silent period is further adopted to sense a high-grade frequency spectrum, thereby confirming whether the master user appears or not. The technical scheme saves the cost for reporting signaling, can quickly sense the existence of the master user, reduces the false alarm probability of the master user, and further improves the throughput of the system.

Description

technical field [0001] The present invention relates to a communication technology, in particular to a hierarchical spectrum sensing method and device in a cognitive wireless network. Background technique [0002] With the growth of wireless communication services, the available frequency bands are increasingly tight, and the problem of insufficient spectrum resources is becoming more and more serious. This has become a basic problem restricting the development of wireless mobile communication in the direction of broadband and ubiquity. Most of the current frequency usage policies in the world adopt the authorization system except for the allocation of very few ISM frequency bands. However, not all authorized users occupy the licensed frequency bands 24 / 7. Some frequency bands are not used by users for part of the time, and others are occasionally occupied. In this way, even if the system spectrum utilization rate is very low, it is still impossible to allocate idle spectrum...

AI Technical Summary

Problems solved by technology

[0004] Both of the above two spectrum sensing schemes have certain problems. Among them, the first technical scheme includes the following disadvantages: the scheme requires a long sensing time when performing the spectrum sensing algorithm on the full frequency band, resulting in The silent period adopted is on the order of hundreds of milliseconds or even seconds, which will not only greatly reduce the throughput of the cognitive wireless network system, but also impair the communication quality and service experience of cognitive users;

[0005] The second technical solution includes the following disadvantages: First, due to the characteristics of this solution, the cognitive wireless network cannot use all its working frequency bands regardless of whether the primary user is present or not, resulting in a waste of frequency resources and at the same time It also greatly reduces the throughput of the cognitive wireless network; secondly, due to the polling characteristics of the working frequency band of the cognitive wireless system in this scheme, the cognitive system and users need to frequently hop frequency to keep the spectrum sensing algorithm running normally. This makes the realization and deployment of the cognitive wireless network system more difficult; third, because the cognitive user can only obtain the sensing results of the full frequency band after the entire round of polling is completed, and can only report to the cognitive wireless network base station after that, it needs to wait The time is relatively long, if there is a main user, it will not be able to respond quickly

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