Joint Throughput Maximization and Power Control in Poisson CoopMAC   Networks
  A cooperative medium access control (CoopMAC) network with randomly distributed helpers is considered. We introduce a new helper selection scheme which maximizes the average throughput while maintaining a low power consumption profile in the network. To this end, all transmissions are assumed to be performed using power control. We assume that each node can estimate the channel between itself and a receiving node. Then, it evaluates the minimum transmission power needed to achieve the desired signal to noise ratio (SNR). If the required transmission power is less than the maximum transmission power of the node, the communication is regarded as successful. Otherwise, the transmission is canceled. %Also, we classify the helpers into six groups according to their transmission rates IEEE 802.11b Standard. In order to increase the average throughput, we assume that the cooperative link with the highest transmission rate is chosen from those that can successfully forward the source signal to destination. Also, when there are several links with the same rates, the one with minimum required power is given the highest priority. Assuming that the helpers are distributed as a Poisson point process with fixed intensity, we derive exact expressions for the average throughput and the power consumption of the network. Simulation results show that our scheme is able to significantly increase the throughput in comparison to the conventional CoopMAC network. It is also able to reduce the power consumption compared to a network with no power control approach. 
Masoumeh Sadeghi, Homa Nikbakht, Amir Masoud Rabiei, and Vahid   Shah-Mansouri
cs.NI cs.IT math.IT