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The future 5G networks need to support different kinds of business and applications, so the cloud radio access networks (C-RAN) which can provide a centralized collaborative resource management gain through small base stations, and seamless handoff also can be achieved through the overlapping deployment of macro base stations and micro base stations has become one of the important directions in 5G...
A hybrid satellite-aerial-terrestrial system has been recently studied as a promising candidate to meet the urgent communication needs of emergency relief, and a good resource allocation policy is important to solve the contradiction between the sudden growth of victims' demand and the shortage of wireless resource in emergency situation. This paper addresses the joint relay selection and power allocation...
In this paper, we consider the multicast resource allocation problem for video streaming in Orthogonal Frequency Division Multiple Access (OFDMA) systems. The video streams are encoded into base layer (BL) and enhancement layer (EL) data by the hierarchical video coding (HVC) scheme. The basic resource unit is a set of contiguous subcarriers (chunk). The problem is formulated to maximize the sum of...
In this paper, we demonstrate the optimal power allocation for QPSK, 16-QAM, and 64-QAM modulation schedules and the role of channel quality indicator (CQI). We used sigmoidal-like utility functions to represent the probability of successful reception of packets at user equipment (UE). CQI as a feedback to the base station (BS) indicates the data rate that a downlink channel can support. With Levenberg-Marquardt...
In this paper, we propose a novel optimal power allocation method that features a power limit function and is able to ensure more users reach the desired Quality-of-Service (QoS). In our model we use sigmoidal-like utility functions to represent the probability of successful reception of packets at user equipment (UE)s. Given that each UE has a different channel quality and different location from...
In the wake of the extensive application of the fourth generation system, investigations of new technologies have been moving ahead vigorously to embrace the next generation communications in 2020. Thereinto, the technique of ultra-dense networks (UDNs) serves as a key enabler in meeting the roaring mobile traffic demands. With the prevalence of mobile Internet services especially those involve the...
At present, the user experience provided by smart mobile terminals is limited to the battery capacity. This paper focuses on how to improve the energy efficiency of terminals in OFDMA-based wireless multicast systems with frequency-selective channels. We assume that multicast terminals can switch to sleep mode during the transmission of some OFDM symbols according to their OFDMA frame-level quality...
In this paper, the subcarrier and power allocation for video multicast services in wireless OFDMA systems is considered. To overcome the multicast capacity loss caused by the conventional multicast scheme where the rate of a subcarrier is determined by the worst channel user, the fine granularity scalability (FGS) video coding is exploited in the multicast system. The FGS decomposes the video contents...
This paper addresses the optimal multicast resource allocation problem in orthogonal frequency division multiple access (OFDMA) system, where the fine granularity scalability (FGS) video coding is exploited to perform source coding. With FGS, the multicast information is coded into base layer data and enhancement layer data, and there is a predefined proportional rate ratio between the transmission...
In cognitive radio (CR) systems, efficient spectrum sensing ensures secondary users (SUs) to successfully access the spectrum hole. Typically, the detection problem has been studied separately from the optimization of throughput of secondary network. However, due to non-zero probabilities of miss detection and false alarm, the sensing phase has an impact on the throughput of CR networks as well as...
Background and aims Plant root placement is highly plastic in order to acquire patchily distributed nutrients and to ensure their survival, growth and reproduction. Considering the spatial extension of clonal organs, we selected two clonal plants (Leymus chinensis (Trin.) Tzvel. and Hierochloe glabra Trin.) to determine the spatio-temporal effects of environmental heterogeneity on belowground organs...
This paper takes into account the uncertainty of the primary users' locations and transmission power in designing an optimal downlink scheduling scheme for cognitive radio cellular networks (CogCells). Localization technique is exploited to estimate the position and transmission power of the primary user (PU) transmitting on specific channel. The objective of our scheduling scheme is to maximize the...
Emergent computation is a relatively new approach for understanding the behaviors of complex systems. Central to this approach is the idea that system-level behavior emerges from interaction among individual elements. This paper proposes a network emergent computation model based on cellular automaton, which introduces network operating mechanism, such as store-and-forward, adjacency interaction,...
The downlink zero-forcing beamforming strategy in the case of random packet arrivals is investigated. Under this setting, the relevant fairness criterion is the stabilization of all buffer queues which guarantees a bounded average delay for all users. It has been shown that allocating resources to maximize a queue-length-weighted sum of the rates is a stabilizing policy. However, the high complexity...
Resource allocation problem in multiuser multiple input single output-orthogonal frequency division multiple access (MISO-OFDMA) systems with downlink beamforming for frequency selective fading channels is studied. The article aims at maximizing system throughput with the constraints of total power and bit error rate (BER) while supporting fairness among users. The downlink proportional fairness (PF)...
Resource selection is an important issue of grid computing. If a grid job can stably gain enough CPU time from the same resources, not only the execution time of the job but also the frequency of resource reallocation is effectively minimized. However, most of the proposed methods are not effective enough to resolve the problem of resource selection in computational grids. The main reason is that...
Large data centers usually host many different services on a shared computing infrastructure, for which on-demand resource management is necessary to maximize providers' revenues by meeting service quality targets at least operational cost. This paper presents a novel architecture of autonomic resource management framework based on virtualized service-oriented computing (SOC) environment. A non-linear...
The remote sensing information service grid node (RSIN) is a tool for dealing with climate change and quantitative environmental monitoring. Based on the high-throughput computing grid, RSIN enables a workflow management system for data placement. The accompanying unified data-and-computation-schedule algorithm helps load balancing between and within workflow steps.
This driven by the need to promote a more efficient use of radio resources and improve the operators' profits, resource allocation has turned into a joint technical and economical problem. At the same time, as a possible enabling solution, game theory has been applied to either dynamic spectrum access (DSA) or joint radio resource management (JRRM) in wireless communication research recently. In this...
The inter-cell interference of orthogonal frequency division multiple access (OFDMA) based multi-cell distributed network architecture is analyzed. Based on generalized distributed cellular architecture-group cell, the interference condition without power control and with power control is analyzed respectively, and the system outage probability compared to traditional cellular structure is evaluated...
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