Energy efficient content distribution over wireless networks with mobile-to-mobile cooperation / by Lina Kanj Al-Kanj.

Abstract

One class of emerging mobile applications is simultaneous common content distribution to a group of mobile terminals (MTs) over a broadband wireless network, such as news download (e.g., breaking news), multimedia multicasting (e.g., live sport events), or file distribution (e.g., device configuration files). In a traditional scenario, the BS can unicast the content to each MT on a dedicated channel with a customized rate depending on its channel conditions, or the BS can multicast the content once to the MTs with a multicasting bit rate that is limited by the worst channel conditions among them. However, the bandwidth constraints for wide wireless area networks limit the users' bit rates, consequently, increasing the download time and the energy consumption of the MTs. Recent studies have shown that the high energy consumption of battery-operated MTs will be one of the key limiting factors in future wireless communication systems. To overcome the throughput and power limitations of a given long range wireless technology, cooperative content distribution approaches have been proposed in the literature, by allowing the MTs to cooperate with each other over a short range wireless technology with higher data rates, due to the proximity of the MTs. In this case, the BS can unicast or multicast the content to a selected subset of the MTs based on some predefined criteria these MTs can then forward the received data to other MTs over mobile-to-mobile links. In the cooperative approaches, the MTs actively use two wireless interfaces: one interface to communicate with the BS over a long range (LR) wireless technology (such as WLAN, UMTS-HSPA, WiMAX, or LTE) and another interface to communicate with other MTs using a short range (SR) wireless technology (such as Bluetooth or WLAN ad hoc mode). Many heuristic algorithms for cooperative content distribution have been proposed in the literature that take into account only selected network parameters to simplify the proposed algorithms. However, optimized solutions have b