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Available approaches to solving the problem of frequency resource distribution in the wireless mesh-networks with WiMAX technology are analyzed; the requirements of the systems nature on the structure and contents of the frequency resource distribution mathematical model are stated on the basis of these approaches. The frequency resource distribution mathematical model is offered as a problem of subchannels'...
This paper presents new energy-aware QoS scheduling and call admission control algorithms for WiMAX IEEE 802.16e broadband wireless access standard. The scheduling algorithm works at MAC layer and is designed towards minimizing power consumption at mobile stations supporting multiple UGS connections, while meeting the QoS requirements of the connections. The scheduling algorithm uses a novel idea...
In this paper, we study an uplink ICIC (Inter-cell Interference Coordination) mechanism based on the principle of soft frequency reused SFR. The proposed approach exploits the flexibility of frequency selective scheduling and rate adaptation, while dynamically limiting the interference experienced by the neighboring cells to a predefined limit. The technique provides a flexible and efficient way of...
Careful management of inter-cell interference is important in OFDMA based systems such as LTE. In this paper, we study an uplink ICIC (Inter-cell Interference Coordination) mechanism, which fully utilizes the flexibility of frequency selective scheduling and rate adaptation, while dynamically limiting the interference experienced by the neighboring cells. This technique can be seen as an extension...
Uplink scheduling for MIMO-OFDM users is considered in this paper. Each user spatially multiplexes his data over multiple transmit antennas using V-BLAST scheme. This spatial multiplexing (SM) scheme provides high data rates while multi-user diversity obtained from scheduling improves the performance of the uplink system. The greedy scheduler selects one user at a time based on a criterion that minimizes...
Most of IEEE 802.16e resource allocation proposals only focus on how to allocate the resources to meet QoS parameters such as throughput, delay, and delay-jitter. As described in the standard, the mapping from the allocation into downlink subframe for each burst needs to be in a rectangular shape. The rectangular mapping problem is a variation of a bin or strip packing problem, which is known to be...
In OFDMA systems, reducing the inter-cell interference among adjacent cells is a very important issue especially for the cell-edge users. In this paper, we propose a distributed algorithm that maximizing the system total throughput considering proportional fairness. In our proposed algorithm, the frequency resources in each cell is divided into high and low power regions. The bandwidth allocations...
Uplink scheduling in LTE systems is considered. Two low complexity heuristic algorithms for suboptimal subcarrier allocation are proposed and compared to other algorithms in the literature. Throughput and fairness analysis of the different algorithms are performed via Monte-Carlo simulations. The proposed algorithms are utility maximizing algorithms that can be used with various utility functions...
Self-optimization of the network, for the purposes of improving overall capacity and/or cell edge data rates, is an important objective for next generation cellular systems. We propose algorithms that automatically create efficient, soft fractional frequency reuse (FFR) patterns for enhancing performance of orthogonal frequency division multiple access (OFDMA) based cellular systems for forward link...
In this paper we study the performance of the heuristic localized gradient algorithm (HLGA) that was designed for uplink scheduling in 3G long term evolution (LTE) systems. The performance of the algorithm is examined when dynamic traffic models are assumed. With dynamic traffic, users will have different buffer occupancies. The amount of resources granted to a user need to be mapped to the size of...
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