Power Allocation Scheme for Channel Capacity Maximization in Multi-relay Amplify-and-forward Cooperative System

2015 ◽  
Vol 12 (4) ◽  
pp. 1365-1372 ◽  
Author(s):  
Suoping Li
Keyword(s):  
Power Allocation ◽  
Channel Capacity ◽  
Cooperative System ◽  
Allocation Scheme ◽  
Amplify And Forward ◽  
Capacity Maximization

Modified genetic algorithm based power allocation scheme for amplify-and-forward cooperative relay network

2018 ◽  
Vol 69 ◽  
pp. 628-641 ◽  
Author(s):  
Anand Gachhadar ◽  
MHD Nour Hindia ◽  
Faizan Qamar ◽  
M. Hassam Shakil Siddiqui ◽  
Kamarul Ariffin Noordin ◽  
...  
Keyword(s):  
Genetic Algorithm ◽  
Power Allocation ◽  
Relay Network ◽  
Cooperative Relay ◽  
Allocation Scheme ◽  
Amplify And Forward ◽  
Modified Genetic Algorithm ◽  
Cooperative Relay Network

scholarly journals Layered Capacity-Based Relay-and-Antenna Joint Selection for MIMO-AF-Multiple-Relay Systems in Correlated Channels

2012 ◽  
Vol 2012 ◽  
pp. 1-9
Author(s):  
Chia-Chang Hu ◽  
Jheng-Siang Li ◽  
Bo-Liang Wu
Keyword(s):  
Fading Channels ◽  
Channel Capacity ◽  
Antenna Selection ◽  
Selection Strategy ◽  
Destination Node ◽  
Hardware Complexity ◽  
Amplify And Forward ◽  
Relay Systems ◽  
Capacity Maximization ◽  
Multiple Relay

A computationally efficient two-stage greedy capacity maximization (GCM) relay-and-antenna joint selection is proposed for a dual-hop nonregenerative amplify-and-forward (AF) multiple-input multiple-output (MIMO) multiple-relay system with multiple antennas equipped at each node in correlated fading channels. This modified GCM (MGCM) antenna selection strategy selects a subset of antenna pairs from available relays based on the concept of channel capacity maximization subject to an optimal power allocation constraint across the activated antenna pairs. In order to reduce system hardware complexity, antenna selection schemes are performed at the destination node as well. Finally, simulations are conducted to compare the channel capacity of the proposed two-layered antenna selection technique with other existing antenna selection algorithms for half-duplex AF-MIMO multiple-relay systems.

Secrecy Rate and Optimal Power Allocation of the Amplify-and-Forward Relay Wire-Tap System

2016 ◽  
Vol 2 (1) ◽  
pp. 1
Author(s):  
Cuong Dang ◽  
Leonardo J. Rodr´ıguez ◽  
Nghi H. Tran ◽  
Forrest Sheng Bao ◽  
Shivakumar Sastry
Keyword(s):  
Power Allocation ◽  
Secrecy Capacity ◽  
Optimal Power Allocation ◽  
Allocation Scheme ◽  
Amplify And Forward ◽  
Secrecy Rate ◽  
Joint Power ◽  
Power Constraints ◽  
Optimal Power ◽  
Af Relay

In this research work, we investigate the secrecy rate and optimal power allocation schemes for a half-duplex (HD) wire-tap Rayleigh fading channel in which a source wishes to communicate securely to a destination in the presence of an eavesdropper and under the aid of an amplify-and-forward (AF) relay. The secrecy capacity and the corresponding optimal power allocation schemes are examined under both individual and joint power constraints. Due to the absence of an insightful expression of the secrecy rate for a given power allocation scheme, determining such secrecy capacity is challenging. To overcome this issue, we first propose a novel method to calculate the expectation of an exponentially distributed random variable using the exponential integral function. By exploiting this calculation, we then establish the average secrecy rate of the considered AF relay channel in closed-form. By examining the quasi-concavity of the optimal power allocation problem, it is then concluded that the problem is quasi-concave. As such, the globally optimal solution exists and is unique for both individual and joint power constraints. A simple root finding method then can be applied into the derived close-formed formula to approximately calculate the optimal power allocation scheme to achieve the secrecy capacity. Numerical results are then provided to confirm the accuracy of the derived formula and the optimality of the proposed power allocation.

scholarly journals The Optimal Power Allocation with Hybrid Relaying Based on Channel Condition

2018 ◽  
Author(s):  
Junpyo Jeon ◽  
Yeonggyu Shim ◽  
Hyuncheol Park
Keyword(s):  
Power Allocation ◽  
Relay Network ◽  
Achievable Rate ◽  
Optimal Power Allocation ◽  
Allocation Scheme ◽  
Amplify And Forward ◽  
Decode And Forward ◽  
Transmit Power ◽  
Optimal Power ◽  
Af Relay

This paper considers a hybrid relay network consisting of the source, the amplify-and-forward (AF) relay, the decode-and-forward (DF) relay, and the destination. We propose the optimal power allocation schemes between two different relays which maximize the achievable rate under a sum relay power constraint for given channel gains and transmit power from source. By solving the optimization problem to maximize the achievable rate for each relay network, the transmit power values in closed-form are derived. When the channel gains are the same, the optimal power allocation scheme for AF-DF relay network proves that a more power should be allocated at the first relay to maximize the achievable rate. In case of the DF-AF relay network, we derive the optimal power allocation scheme for the possible four cases. Under the same SNR condition at the first hop, we show that the achievable rate of AF-DF relay network is greater than that of DF-AF relay network when the channel gain between two relays is higher than that between the second relay and destination. Simulation results show that the proposed power allocation schemes provide a higher achievable rate than the equal power allocation schemes.

Sign in / Sign up

Export Citation Format

Share Document