White Space Ecosystem: A secondary network operator´s perspective

The successful deployment of a TV white space network requires the coordination and cooperation of all involved parties (including licensees, databases, secondary operators, and end-users), which form the White Space Ecosystem. In this paper, we study the white space ecosystem from the perspective of secondary network operators. Specifically, we consider a competitive white space network, where multiple secondary operators compete for the same pool of end-users. Each operator serves the attracted end-users by using either the dedicated spectrum (pre-ordered in advance) or the shared spectrum (requested in real-time). The key problem for each operator is to (i) determine the order quantity of dedicated spectrum, considering the uncertainty of end-user demand, and (ii) decide the price to the end-users, considering the competition of other operators. We formulate the interaction of operators as a non-cooperative Price-Quantity competition game (PQ-game), and study the existence and uniqueness of the Nash equilibrium (NE) systematically. We further characterize the impacts of the operator competition on the social welfare and the operators´ own profits. Our results show that such impacts depend largely on the operators´ cost of purchasing spectrum from the database or licensee: when the cost is low, the operator competition will decrease the social welfare and the operators´ profits; when the cost is high, however, the competition will increase the social welfare and the operators´ profits.