Some Comments to Application of Cognition Principle in Wireless Networks

Inhalt:
Most of the publications related to Cognitive Radio (CR) Wireless Networks are devoted mainly to Spectrum Sensing problems and Resource Allocation for Cognitive Users (SU). So far, there is a high grade of understanding on how to provide solutions for the above mentioned problems as well as for the problems related to them. In this paper, Cognition is considered and tackled somehow in the more general sense as it was recently proposed by N. Devroye, V. Tarokh et. al.: how to create a cognitive radio channel with potentially high spectral efficiency. It was shown that the problems that were widely considered before, such as spectrum sensing and system collaboration, etc, can be treated as special cases in the framework of this theory. In this paper the creation of the Cognitive radio channel is analyzed together with Interference Aware principle in order to additionally mitigate the interferences produced by Cognitive User to the Primary User (PU) receiver for the case of 2x2 interacted Gaussian channels. As a main result, the achievable region for transmission rates is presented for this case. Results show that there is a significant improvement zone for the case of the CR channel (together with interference mitigation), when the CR applies high transmission rates. Thus, the spectral efficiency of the network can be considerably increased. Some other comments regarding to the application of Interference Aware principle are considered as well.