@book{197e482192dc4da683469a18087a8414,
title = "Cognitive radio: An intelligent wireless communication system",
abstract = "The radio frequency spectrum is a scarce natural resource and its efficient use is of the utmost importance. The spectrum bands are usually licensed to certain services, such as mobile, fixed, broadcast, and satellite, to avoid harmful interference between different networks to affect users. Most spectrum bands are allocated to certain services but worldwide spectrum occupancy measurements show that only portions of the spectrum band are fully used. Moreover, there are large temporal and spatial variations in the spectrum occupancy. In the development of future wireless systems the spectrum utilization functionalities will play a key role due to the scarcity of unallocated spectrum. Moreover, the trend in wireless communication systems is going from fully centralized systems into the direction of selforganizing systems where individual nodes can instantaneously establish ad hoc networks whose structure is changing over time. Cognitive radios, with the capabilities to sense the operating environment, learn and adapt in real time according to environment creating a form of mesh network, are seen as a promising technology.",
keywords = "cognitive network, cognitive radio, radio frequencies, radio frequency identification, frequency management, power control, regulation, spectrum sensing",
author = "Marja Matinmikko and Marko H{\"o}yhty{\"a} and Miia Mustonen and Heli Sarvanko and Atso Hekkala and Marcos Katz and Aarne M{\"a}mmel{\"a} and Markku Kiviranta and Aino Kautio",
note = "Project : 12093 ",
year = "2008",
month = mar,
day = "14",
language = "English",
series = "VTT Research Report",
publisher = "VTT Technical Research Centre of Finland",
number = "VTT-R-02219-08",
address = "Finland",
}