With the introduction of Third Generation Mobile Networks (3G) at the beginning of the 21st century, it became possible to provide broadband services on mobile phones. The limitedness and scarcity of available radio spectrum might convert the 3G market into a monopoly. Besides, the typical approach of static spectrum allocation, might result in an inefficient utilization of resources. That's because the provider which has obtained the license to use spectrum, usually does not receive enough request for services to utilize the entire spectrum with an acceptable efficiency. A Mobile Virtual Network Operator (MVNO) is a kind of mobile operator, which does not possess its own radio infrastructure and would obtain its resources from the main 3G operators that have the license to access radio spectrum. The coexistence of these MVNOs and main operators, is expected to make the market more competitive and provide subscribers with a broader range of service options. Besides, MVNOs will make a better utilization of the available radio spectrum. One of the lucrative sorts of MVNOs, is the one which focuses on providing mobile services at a discounted price. These operators try to buy resources at wholesale prices from the main operators and hence provide their subscribers with cheaper services. The lower prices come from the fact that the main operators tend to somehow sell their unused resources, and hence gain more profit. Based on this fact, an MVNO can buy unused resources at a bargain price. The idea of MVNOs and the economic and technical aspects of their operation has been the subject of extensive research. The results of these studies show that the main part of MVNO's expenses is the cost of leasing resources, specially radio spectrum, from the main operators. Therefore, it is important to pay special attention to the mechanisms of spectrum sharing and pricing among the main and virtual operators. One of the interesting suggestions on the mechanism of spectrum pricing, is the idea of exploiting game theoretic approaches, especially the auction theory, to evaluate the leased resources in a fair manner, which takes into account the interests of both main and virtual operators. The main operators would like to gain profit, whilst keeping their own subscribers satisfied with their quality of services. On the other hand, the virtual operators want to obtain resources with prices as low as possible. Therefore the tradeoff between cost and income should be addressed effectively. In the current thesis, one sort of auction is reviewed thoroughly. Simulation results demonstrate the effectiveness of this approach. In addition to that, we will suggest a method to improve the.... Keywords: MVNO, Auction, Game Theory, Third Generation, 3G, SCTP, LT Codes