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Green communication has recorded much attention in industry, academia and government. It has been recorded that information communication and technology nodes consume roughly 3% of the world-wide energy supply and are responsible for 2% of the global carbon dioxide (CO 2 ) emission. As a result, researchers have devoted huge attention to prevent its growth. In order to address this problem we studied coded packet approach, which is the current method of minimising energy in wireless multicast networks. Then, we propose novel approaches that are based on data envelopment analysis (DEA) to further optimise energy consumption in wireless multicast networks. We found that existing approaches to energy efficient multicast are unsuitable for evaluating efficiency adequately. This paper takes the position that true efficiency evaluation is obtained when both inputs and outputs with multiple variables are considered in measuring performance using ratios of weighted outputs to weighted inputs. As a result, we developed the input-oriented variable return to scale (VRS) envelopment with slacks models for energy efficiency in ad hoc wireless multicast networks. We explored the random linear network coding (RLNC) based on simulation approach and compared the results with the input-oriented VRS DEA envelopment with slacks approach. The results show the DEA approach substantially saves energy compared to the RLNC. Furthermore, we show that DEA method has the capability to identify which ad hoc network is inefficient and projected them onto the efficient frontier.

In this study, the maximum achievable information transmission rate of spectrum sharing cognitive radio with maximal ratio combining (MRC) antenna diversity technique is investigated when the channel between the secondary transmitter and the primary receiver and that between the secondary transmitter and the secondary receiver suffer Nakagami-m fading. With an assumption that both channels encounter Nakagami-m fading and the transmission of the secondary transmitter is subject to average interference power constraint, the approximated expressions for analyzing the effective capacity and the ergodic capacity of cognitive radio users with MRC are presented. The two capacity models are compared. In the case of the effective capacity, it is shown that different applications or users with different quality of service (QoS) requirements can be supported in cognitive radio, and when the delay QoS decreases, the effective capacity approaches the ergodic capacity.

The paper studies the problem of minimum-cost multicast connections over coded packet networks and introduces a new technique for evaluating the performance of wireless network by exploring data envelopment analysis tool. It also explores the use of network coding in wireless multicast and investigates its cost effectiveness and efficiency. Earlier work on multicast connections focuses largely on cost effectiveness, rather than cost efficiency. Simulation results show that the network coding scheme based on multicast traffic, perform better in terms of effectiveness and efficiency compared to the existing multicast incremental power algorithm.

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