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Abstract-Successive Interference Cancellation (SIC) is a physical-layer technique that enables reception of multiple overlapping transmissions. While SIC has the potential to boost the network throughput, if the MAC protocol employed in the network is agnostic to such a capability at the physical-layer, the full potential of SIC can not be utilized in the network. There have been a number of studies to design new SIC-aware MAC protocols or adjust the existing protocols to exploit SIC. Despite that, the exact effect of MAC protocols on the throughput of SIC-enabled networks is unknown. In this paper, we propose a novel SIC-aware MAC protocol based on the disparity of user channels in a wireless network and analyze its performance. We consider a simple random access protocol with no SIC as the base configuration and compare it with three other configurations with different levels of SIC-awareness. We show that while a SICenabled physical layer without a SIC-aware MAC protocol can increase the throughput of the network by 1.5x, a specifically designed MAC protocol is far more efficient achieving up to 3.3x improvement in throughput. Our SIC-aware MAC protocol is fully distributed and hence subject to selfish behavior of users. Thus, we also consider the case where the users behave selfishly. We model our proposed protocol as a one-shot simultaneous move game and derive a mixed strategy Nash equilibrium. We also show that we can set the cost of packet transmission in such a way that we get the optimal system throughput at the Nash equilibrium.

Abstract-In this paper, we study the problem of uplink scheduling in wireless networks with successive interference cancellation (SIC). With SIC, concurrent transmissions, if properly scheduled, can be successfully decoded at a receiver. The scheduler decides: (i) in which timeslot, and (ii) in what order in a time-slot to decode each transmission in order to maximize the system utility. These two scheduling decisions effectively determine the rates allocated to concurrent transmissions, which in turn determine the throughput and fairness of the system. We consider two scheduling problems, namely the Maximum Throughput Scheduling and Proportional Fair Scheduling. We prove the first problem is NP-hard, while the second seemingly harder problem can be solved in polynomial time.

As nodes in wireless sensor networks are usually supplied by a simple non rechargeable battery, the energy available in these nodes is very limited. Moreover, this limited energy is mostly consumed in transmission and reception of data. As transmission and reception is highly affected by routing algorithms, designing a proper routing algorithm will prolong the network lifetime. In this paper we proposed a novel routing algorithm, called Locality-Aware Diffusion (LAD) that leverages spatial locality of sensed data in sensor networks to reduce energy consumption and prolong the network lifetime. The proposed algorithm is an extension to Shortest Path Tree which is a common approach in routing algorithms. Simulation results show the validity and effectiveness of the proposed algorithm.