Mobile Fog Computing-Assisted Resource Allocation for Two-Hop SWIPT OFDM Networks

The mobile fog computing-assisted resource allocation (RA) is studied for simultaneous wireless information and power transfer (SWIPT) two-hop orthogonal frequency division multiplexing (OFDM) networks, where a decode-and-forward (DF) relay first harvests energy from signals emitted by a source and then helps the source to forward information to its destination by using the harvested energy. Power splitting (PS) strategy is adopted at the relay and a different PS (DPS) receiver architecture is proposed, where the PS factors of all subcarriers are different. A RA problem is formulated to maximize the system’s achievable rate by jointly optimizing subcarrier pairing, power allocation, and PS factors. Since the RA problem is a nonconvex problem and is difficult to solve, an efficient RA algorithm is designed. As the wireless channels are fast time-varying, the computation is performed in mobile fog node close to end nodes, instead of remote clouds. Results demonstrate that the achievable rate is significantly increased by using the proposed RA algorithm. It is also found that the computation complexity of RA algorithm of DPS receiver architecture is much lower than the existing identical PS (IPS) receiver architecture, and thus the proposed DPS architecture is more suitable for computation-constrained fog system.

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Resource Allocation for Decode-and-Forward Relaying Assisted Multi-cell Orthogonal Frequency Division Multiplexing Systems with Frequency Planning

Wireless Personal Communications ◽

10.1007/s11277-014-1887-8 ◽

2014 ◽

Vol 79 (1) ◽

pp. 789-810

Author(s):

Yaru Fu ◽

Qi Zhu

Keyword(s):

Resource Allocation ◽

Orthogonal Frequency Division Multiplexing ◽

Frequency Division Multiplexing ◽

Frequency Division ◽

Decode And Forward ◽

Frequency Planning ◽

Multiplexing Systems

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QoS-Constrained Resource Allocation Scheduling for LTE Network

International Journal of Wireless Networks and Broadband Technologies ◽

10.4018/ijwnbt.2015010101 ◽

2015 ◽

Vol 4 (1) ◽

pp. 1-15 ◽

Cited By ~ 5

Author(s):

Hung-Chin Jang ◽

Yun-Jun Lee

Keyword(s):

Resource Allocation ◽

Data Transmission ◽

Orthogonal Frequency Division Multiplexing ◽

Transmission Rate ◽

High Mobility ◽

System Throughput ◽

Frequency Division ◽

High Data ◽

Single Carrier ◽

Allocation Method

The goal of LTE (Long Term Evolution) is to provide high data transmission rate, scalable bandwidth, low latency, high-mobility, etc. LTE employs OFDM (Orthogonal Frequency Division Multiplexing) and SC-FDMA (Single Carrier - Frequency Division Multiple Access) for downlink and uplink data transmission, respectively. As to SC-FDMA, there are two constraints in doing resource allocation. First, the allocated resource blocks (RBs) should be contiguous. Second, those of the allocated RBs are forced to use the same modulation technique. The aim of this research is to propose a QoS-constraint resource allocation scheduling to enhance data transmission for uplink SC-FDMA. The proposed scheduling is a three-stage approach. In the first stage, it uses a time domain scheduler to differentiate user equipment (UE) services according to their distinct QoS service requirements. In the second stage, it uses a frequency domain scheduler to prioritize UE services based on channel quality. In the third stage, it limits the number of times of modulation downgrade of RBs allocation in order to enhance system throughput. In the simulations, the proposed method is compared to fixed sub-carrier dynamic resource allocation method and adaptive dynamic sub-carrier resource allocation method. Simulation results show that the proposed method outperforms the other two methods in terms of throughput, transmission delay, packet loss ratio, and RB utilization.

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Outage-Based Resource Allocation for DF Two-Way Relay Networks with Energy Harvesting

Sensors ◽

10.3390/s18113946 ◽

2018 ◽

Vol 18 (11) ◽

pp. 3946 ◽

Cited By ~ 1

Author(s):

Chunling Peng ◽

Fangwei Li ◽

Huaping Liu ◽

Guozhong Wang

Keyword(s):

Resource Allocation ◽

Energy Harvesting ◽

Outage Probability ◽

Relay Network ◽

Total Power ◽

Power Splitting ◽

Decode And Forward ◽

Resource Allocation Algorithm ◽

Joint Resource Allocation ◽

System Outage Probability

A joint resource allocation algorithm to minimize the system outage probability is proposed for a decode-and-forward (DF) two-way relay network with simultaneous wireless information and power transfer (SWIPT) under a total power constraint. In this network, the two sources nodes exchange information with the help of a passive relay, which is assumed to help the two source nodes’ communication without consuming its own energy by exploiting an energy-harvesting protocol, the power splitting (PS) protocol. An optimization framework to jointly optimize power allocation (PA) at the source nodes and PS at the relay is developed. Since the formulated joint optimization problem is non-convex, the solution is developed in two steps. First, the conditionally optimal PS ratio at the relay node for a given PA ratio is explored; then, the closed-form of the optimal PA in the sense of minimizing the system outage probability with instantaneous channel state information (CSI) is derived. Analysis shows that the optimal design depends on the channel condition and the rate threshold. Simulation results are obtained to validate the analytical results. Comparison with three existing schemes shows that the proposed optimized scheme has the minimum system outage probability.

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