In this paper, the energy efficiency of multihop relaying over Nakagami-m fading channels is investigated. The “consumption factor”, adopted as a metric to evaluate the energy efficiency, is derived for both amplify-and-forward and decodeand-forward relaying strategies. Then, based on the obtained expressions, we propose a power allocation strategy maximizing the consumption factor. In addition...

We consider an energy harvesting communication system where the temperature dynamics is governed by the transmission power policy. Different from the previous work, we consider a discrete time system where transmission power is kept constant in each slot. We consider two models that capture different effects of temperature. In the first model, the temperature is constrained to be below a critic...

in this paper, downlink resource allocation for a sparse code multiple access (scma) based heterogeneous  cellular networks (hcn) is investigated. the main aim of this paper is to obtain joint power allocation and codebook assignment to achieve the least total system transmit power. in this regard, the proposed objective function is formulated as total transmit power subject to users minimum ra...

We study optimal constant-rate coding schemes for a block-fading channel with strict transmission delay constraint, under the assumption that both the transmitter and the receiver have perfect channel-state information. We show that the information outage probability is minimized by concatenating a standard “Gaussian” code with an optimal power controller, which allocates the transmitted power ...

In a de-regulated open access environment, reactive power is one of the ancillary services which must be provided by an Independent System Operator (ISO). In this paper, a new algorithm is proposed in which reactive power resources are initially so tuned that optimum security in terms of voltage profile and voltage stability are achieved while at the same time, the system losses are minimized. ...

This paper investigates energy efficient power allocation scheme for OFDM-based cognitive opportunistic relaying links (CORL), where secondary users (SUs) may incorrectly sense the unlicensed spectrum and hence transmit data in collision. We aim to maximize the energy efficiency (EE) by optimal and low complexity power allocation design. At first, an energy efficient power allocation optimizati...

We obtain the (Shannon) optimal power and rate allocation strategies for the uplink on single cell systems. For an N user system, we show that successive decoding which is independent of channel state is optimal in the Shannon sense. Using this result, we frame a simple N dimensional convex optimization problem, which is solved to obtain optimum power and rate allocation as explicit functions o...

As wireless networks evolve to orthogonal frequency division multiple access (OFDMA) systems, inter-cell interference control becomes a critical issue in radio resource management. The allocation of the same channels in neighbor cells cause inter-cell interference, so the channel allocation needs to be taken carefully to lower the inter-cell interference. For channel allocation, we consider two...

This paper obtains optimal power allocation to the data aggregator units (DAUs) and relays for cognitive wireless networks in a smart grid (SG). Firstly, the mutual interference between the primary user and the DAU are considered, and the expressions of the DAU transmission signal are derived based on the sensing information. Secondly, we use the particle swarm optimization (PSO) algorithm to s...