A real time QoS aware adaptive radio resource management algorithm for downlink of multi-cell and multi user MIMO-OFDMA system. This purposed scheduling algorithm takes account queue status, transmission rates, channel state information and priority of the user for subcarrier, power and bit allocation in MU-MIMO-OFDMA system. Subcarrier selection is based on the priority of the user and eigenva...

Interference between primary user (PU) and secondary user (SU) transceivers should be mitigated in order to implement underlay spectrum sharing in cognitive radio networks (CRN). Considering this scenario, an improved joint subcarrier and bit allocation scheme for cognitive user with primary users’ cooperation (PU Coop) in CRN is proposed. In this scheme, the optimization problem is formulated ...

In this paper, we propose a subcarrier allocation and subcarrier permutation scheme for an OFDMbased two-way relay network. The proposed scheme consists of two stages: the subcarrier allocation with fixed subcarrier permutation and the subcarrier permutation for a given subcarrier allocation. Simulation results show that the proposed scheme improves spectral efficiency.

A dynamic resource allocation algorithm to satisfy the packet delay requirements for real-time services, while maximizing the system capacity in multiuser orthogonal frequency division multiplexing (OFDM) systems is introduced. Our proposed crosslayer algorithm, called Dynamic Subcarrier Allocation algorithm for Real-time Traffic (DSA-RT), consists of two interactive components. In the medium a...

Most existing algorithms of simultaneous wireless information and power transfer (SWIPT) for orthogonal frequency division multiplexing (OFDM) systems are studied based on power splitting or time splitting, which lead to time delay and the decrease of subcarrier utilization. In this paper, a multiuser OFDM system with multichannel is established and the subcarriers are divided into two parts. O...

A low complexity dynamic subcarrier and power allocation methodology for downlink communication in an OFDM-based multiuser environment is developed. The problem of maximizing overall capacity with constraints on total power consumption, bit error rate and data rate proportionality among users requiring different QOS specifications is formulated. Assuming perfect knowledge of the instantaneo...

Orthogonal Frequency Division Multiplexing (OFDM) is a form of multicarrier modulation. Different symbols are transmitted over different subcarriers. The use of relays increase the coverage area, improve spectral efficiency and also the network lifetime. On the basis of the amplify and forward relaying mode, a two hop multi relay system is proposed with joint relay selection, subcarrier assignm...

In this paper, we propose to adapt both the modulation scheme and the transmit power in the frequency domain using a heuristic evaluation of the bit error rate (BER) for each subcarrier. The proposed method consists in ordering in terms of fading impact, grouping a certain number of subcarriers and performing local power adaptation in each subcarrier group. The subcarrier grouping is performed ...