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Summary: Future green technologies require the reduction of power consumptions, increasing energy efficiencies, and managing the electromagnetic interference footprints. In this paper, we investigate the use of randomized transmit power strategy in which the nodes transmit with random power in a single‐hop ad hoc wireless network. We assume Nakagami‐m channel with very slow feedback channel for power update commands. Hence, by using the characteristic function of the received power, we develop a new mathematical formulation for the outage probability. Further, we test the developed formulation on the known constant transmit power case and randomized uniform distribution with constant maximum case. We show that the performance in terms of outage probabilities and total power consumption of all nodes is generally poor. Therefore, we extend our results to the case of optimized constant power and propose the use of randomized uniform distribution with optimized maximum power. We show that the proposed power distribution outperforms the previous ones and reduces the overall power consumption by many orders of magnitude. [ABSTRACT FROM AUTHOR]

Abstract: In this paper, we apply the power control concept to optical CDMA star networks. Two approaches are considered, namely, centralized and distributed power control. Both approaches are used to optimize the optical transmit power and to maximize network capacity in terms of the number of users satisfying a target signal to interference (SIR) ratio. Centralized algorithms result in the optimum power vector while distributed algorithms are more suitable for practical system implementation and eliminate the need for a centralized control node. Both analytical and simulation results show significant improvement in the performance of the power controlled optical CDMA system. For instance, in a network of 31 nodes, a doubling of the capacity as compared to the non power control case is obtained. Furthermore, we show in the interference-limited case that the network performance is upper bounded by the number of nodes and the correlation properties of the employed code rather than network attenuation and optical fiber lengths. The concept of network partitioning is then introduced to simplify optimum power calculations. Using network partitioning, we find in the interference-limited case that the optical fibers after the star coupler are irrelevant to the optimum power evaluation. [Copyright &y& Elsevier]