Auction and Game-Based Spectrum Sharing in Cognitive Radio Networks

One of the main reasons behind the concurrent increase in the demand for and congestion of Radio Frequency (RF) spectrum is the rapid development of radio networks of all kinds in our world, which has defiantly changed the public feeling about radio. Nowadays, almost everybody has a mobile phone and radio stations are literary everywhere. Someone can argue that our world is becoming a radio world where waves are weaving everywhere around the Earth. What’s more, this congestion has created a battle between the public, private and military sectors over frequency ownership and has put a premium on the cost of spectrum. According to a recent research introduced by the FCC (Federal Communications Commission) and Ofcom, it was found that most of the frequency spectrum was inefficiently utilized [1-2]. The existing spectrum allocation process, denoted as Fixed Spectrum Access (FSA), headed for static long-term exclusive rights of spectrum usage [3] and shown to be inflexible [4]. Studies have shown, however, that spectral utilization is relatively low when examined not just by frequency domain, but also across the spatial and temporal domains [5]. Thus, an intelligent device aware of its surroundings and able to adapt to the existing RF environment in consideration of all three domains, may be able to utilize spectrum more efficiently by dynamically sharing spectral resources [6 and 7]. Since the 19th century, when the laws of electromagnetic have been discovered and described by the set of Maxwell’s equations and technical devices been invented to produce and use these electromagnetic waves predicted by theory, man has added his own man-made waves to the natural ones [7]. It is fair to say that, from the very beginning of wireless telephony, maritime radio systems has always used shared channels [7-8]. For example, 2,182 KHz is used as a calling frequency as well as emergency signalling frequency and other frequencies are used as working frequencies. If two ships want to communicate, one should identify a working frequency and make a call. By specifying a channel or channels, that ships keep watch on, both emergency and establishing connections between ships can be facilitative. In fact, channel sharing was necessary and effective because of the lack of sufficient channels offered to every single ship and due to the fact that, the typical ship will require far less than a full channel of capacity [7-8]. Around the mid of 1970’s, the FCC permitted land mobile operation on some of the lower UHF channels in several large cities, in order to expand land mobile services. One group of channels was made available to Radio Common Carriers (RCCs) to provide mobile service on a common carrier basis. The FCC adopted rules