Due to the broadcast nature of wireless media, all nodes in the coverage of a transmitter are capable of capturing its signals, thus wireless transmission is sensitive to wiretapping. Several existing schemes place an emphasis on secrecy rate improvement, under the protocols of amplify-and-forward or decode-and-forward, when there are only relay users in the network. We set up a novel communica...

Device-to-device (D2D) communication is proposed as a promising technique of future cellular networks which fulfills its potential in terms of high resource utilization. In this paper, in order to improve the achievable rate of D2D communication and the spectrum utilization, we consider the scenario that multiple D2D pairs can share uplink spectrum resources with multiple cellular users (CUs). ...

Driven by the significant consumer demand for reliable and high data rate communications, the future-generation cellular systems are expected to employ cutting-edge techniques to improve the service provisioning at substantially reduced costs. Cooperative relaying is one of the primary techniques due to its ability to improve the spectrum utilization by taking advantage of the broadcast nature ...

This work proposes a distributed resource allocation (RA) algorithm for packet bit-interleaved coded OFDM transmissions in the uplink of heterogeneous networks (HetNets), characterized by small cells deployed over a macrocell area and sharing the same band. Every user allocates its transmission resources, i.e., bits per active subcarrier, coding rate, and power per subcarrier, to minimize the p...

In this paper, a new subcarrier allocation algorithm is proposed for an OFDMA relay network with multicells. In the proposed algorithm, subcarriers are allocated to users and relays so as to maximize the overall sum of the achievable rate under fairness constraints. Fairness constraints are imposed on the minimum rate requirement of users and the maximum power of base stations and relays. Simul...

Multiple-input multiple-output (MIMO) antennas can be combined with orthogonal frequency division multiplexing (OFDM) to increase system throughput by spatial multiplexing. That is the requirement of high speed future wireless networks such as WLANs and WMANs. This paper investigates the radio resource management problem of MIMO-OFDM based wireless network systems in order to maximize the total...

Orthogonal Frequency Division Multiple Access (OFDMA) is the promising technique for ever increasing demand of high data rate services. This paper proposes the Resource allocation issues for multiuser wireless transmissions, based on orthogonal frequency division multiple Access (OFDMA) and convex optimization techniques which are widely used in the design and analysis of variety of communicati...

This paper considers multi-cell decode-and-forward (DF) relay-aided orthogonal frequency division multi-access (OFDMA) downlink systems, in which all sources and relays are coordinated by a central controller for resource allocation (RA). The improved subcarrier pair-based opportunistic DF relaying protocol proposed and studied in the IEEE International Conference on Communications, Beijing, 37...