The Analysis And Implemetation Of The Application Of Dirty Paper Coding In Cognitive Radio Networks

Nowadays, with the rapid development of the informationization of the whole world, the needs of communication service is increasing rapidly, types of business are increasingly diversified. The application and characteristics of the wireless network has been changed a lot. The needs of the communication spectrum have been growth exponentially and the contradiction between supply and demand issues has become increasingly prominent in the spectrum resources, which impacts the wireless service a lot and turned out to become one of the bottlenecks restricting the development of wireless field. Because of than, nowadays we need new wireless technology which suits today’s wireless environment, and adapts to the change of the electromagnetic environment, and achieves the efficient and orderly sharing of spectrum resources. Thus, the cognitive radio network technology has come into being.In this paper, we firstly studied the overlay model of the cognitive radio networks. In overlay model of the cognitive radio networks, the cognitive user must use some part of its own power to help to send the information of the prime user, and meanwhile, does not affect the signal receiving of the prime user. In order to reach the capacity of the cognitive channel, the cognitive user must use the dirty paper coding technology to cancel the interference of the prime user. In this paper, we studied the channel model of the cognitive radio, the communication model, and analysis the capacity of the cognitive channel. And discuss the communication situation when the cognitive use could sensing some part of the prime user’s signal, and in the generalized fading dirty paper channel, how the cognitive user use the dirty paper coding to reach the channel capacity. In the research of the dirty paper, we first studied the dirty paper channel model, the capacity of the dirty paper channel and the capacity of the dirty paper channel in the real communication environment. We analyze the two proposal of designing of the practical dirty paper coding scheme:the practical dirty paper coding scheme based on the better source coding and the practical dirty paper coding scheme based on the better channel coding. In the practical dirty paper coding scheme based on the better source coding, we studied four different types of quantizer, and propose the practical dirty paper coding scheme based on the LPQ and BPQ. In the practical dirty paper coding scheme based on the better channel coding, we first studied the trellis code modulation, and the turbo trellis code modulation. Finally, we propose a new type of practical dirty paper coding scheme, the trellis-precoding scheme based on the turbo trellis code modulation, and design some simulation on it, which could prove that the trellis-precoding scheme based on the turbo trellis code modulation could get more channel coding gain.