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One of the keys to the success of WiMAX is its capability of supporting traffic with heterogeneous quality of service (QoS) requirements. The current standard specifies the general QoS architecture for WiMAX but the design of the main building blocks (e.g., connection admission control, packet schedulers) is left up to the vendors' implementation. This gap motivates the paper that aims to design and analyse a channel-aware QoS framework for efficiently managing radio resources in a WiMAX network. The proposed architecture integrates the specifications of (1) a connection admission control module and a packet scheduler implemented at the base station (BS) to manage bandwidth requests from the subscriber stations (SSs), and (2) a scheduler at the SS that distributes the granted resources among the active data flows. Simulation results show that the proposed framework enables QoS differentiation and intra-class fairness, and demonstrate that a combined design of the BS and SS schedulers is necessary for effective QoS provisioning. [ABSTRACT FROM AUTHOR]

The design of effective radio resource management policies for group-oriented services in beyond-4G networks is attracting the interest of the research community. Along this line, this paper analyzes some novel approaches that take advantages of the Device to Device (D2D) communication paradigm with the aim of improving the session quality experienced by mobile users in terms of delay and energy consumption. The basic idea is to enable receivers with a bad cellular link from the evolved Node B (eNodeB) to receive the multicast service through another mobile device located in proximity over a direct link. Two schemes are proposed that exploit different radio technologies to enable nearby multicast subscribers to establish direct local links, either Long Term Evolution-Advanced (LTE-A) or Wi-Fi Direct. The effectiveness of the proposed solutions is demonstrated through a comprehensive simulative analysis and compared with traditional techniques that only exploit point-to-multipoint communication from the eNodeB to all the group members not taking advantages of the multi-user diversity or alternative network technologies to serve the multicast users. [ABSTRACT FROM AUTHOR]

The focus of this paper is on a wireless cooperative network architecture, where a group of users exploits short-range wireless links to share the costs of a cellular download. To maximize the efficiency of the communication system, an optimization of parameters such as download time, monetary cost, and energy consumption can be implemented. Following this approach different portions of data shall be assigned for download to the involved users, which will then cooperatively exchange the contents on the short-range link. However, the policy of task assignment to the user terminals has a direct influence on the payoff of the single users, raising fairness issues in real implementation scenarios. Focusing on the energy savings introduced by the wireless cooperative network, in this paper we address the fairness issue by relying on game theoretic bargaining solutions. These solutions, have intrinsic properties to nicely model the duality between fairness and efficiency in the performances. An optimal trade-off algorithm between efficiency and fairness is then introduced, allowing the service coordinator to select the most appropriate bargaining solution and energy savings allocation under different constraints on fairness. [ABSTRACT FROM AUTHOR]

Digital Video Broadcasting for Handheld terminals (DVB-H) is a new standard developed by DVB Project consortium to enable the delivery of broadcast transmissions to mobile terminals (such as, cellular telephone, PDA, pocket PC, etc.). Being the DVB-H network characterized by a cellular structure, a key issue to avoid the service interruption in these systems is the design of effective handoff procedures. This paper introduces a novel seamless handoff approach for DVB-H networks, which is designed to reduce the user terminal power consumption and to make the handoff algorithm be driven by the quality of the user received signal. This implies the adoption of a method based on the constant monitoring of the Modulation Error Rate (MER), instead of standard RSSI-based procedures. Additional advantages in terms of power saving derive from the use of an Active Handoff procedure that exploits the UMTS return channel as an interaction channel. The proposed scheme has been successfully tested and obtained results make us confident that this can be an interesting research direction to investigate in the view of effective DVB-H handoff protocol design. [ABSTRACT FROM AUTHOR]