Dynamic spectrum access method and system applied to cognitive radio networks

Abstract

The invention discloses a dynamic spectrum access method and a dynamic spectrum access system which are applied to cognitive radio networks. The method comprises the following steps of: after a service of a cognitive user arrives, detecting whether a channel is idle, and if so, capturing state transition of a recording system by using a continuous time Markov chain (CTMC), calculating optimal access information by combining relevant parameters of a master user and the cognitive user and transmitting the information to the cognitive user; allowing the cognitive user to access and transmitting the service according to the calculated optimal access information; if the service QoS of the cognitive user is detected to decline sharply in the process of transmission, forcing the cognitive user to exit the channel; and if not, allowing the cognitive user to exist the channel after the cognitive user finishes the service. The scheme provided by the invention ensures the QoS of the master user under the circumstances of a false alarm or an undetected error when the cognitive user carries out spectrum detection, and realizes the balance between operation efficiency and use fairness of the channel.

Description

technical field [0001] The present invention relates to a wireless communication system spectrum access technology, in particular to a dynamic spectrum access method and system applied in a cognitive wireless network. Background technique [0002] With the continuous emergence of various new wireless communication technologies and the rise of various wireless services, "spectrum scarcity" has become a bottleneck restricting the development of next-generation wireless communication systems. The traditional method is to allocate the radio communication spectrum to different services in a fixed way. Generally, a frequency band is only used independently by one wireless communication system, and is allocated and authorized by the state. There are guard frequency bands between different services, and wireless communication systems can use their own frequency bands without interfering with each other. [0003] However, with the increasing complexity of the wireless network struct...

AI Technical Summary

Problems solved by technology

[0007] However, all current prior art literature assumes that when cognitive users perform spectrum detection, the spectrum detection on the physical layer is perfect, that is, there will be no false alarms and false detections. However, in practice, It is impossible to achieve perfect spectrum detection at the physical layer, and there will be false alarms and false detections. In this case, cognitive users still access according to the methods in these documents, which will inevitably affect the QoS of the primary user

Images