We investigate the achievable performance gain that network coding (NC) when combined with successive interference cancellation (SIC) brings to a multihop wireless network. While SIC enables concurrent receptions from multiple transmitters, NC reduces the transmission time-slot overhead, and each of these techniques has shown independently great benefits in improving the network performance. We present a cross-layer formulation for the joint routing and scheduling problem in a wireless network with NC (with opportunistic listening) and SIC capabilities. We use the realistic signal-to-interference-plus-noise ratio (SINR) interference model. To solve this combinatorially complex nonlinear problem, we decompose it (using column generation) to two linear subproblems-namely opportunistic NC aware routing and scheduling subproblems. Our scheduling subproblem consists of activating noninterfering NC components, rather than links, which do not interfere with each other and will be used to route the traffic. We further extend our design to consider a multirate multihop wireless network with interference cancellation capabilities. We use numerical evaluation to present the achieved performance gain and compare our work to three other models: a base model with no NC and SIC, a model with only NC, and a model with only SIC capabilities. The numerical results show that our proposed method (both with and without variable transmission rate selection) achieves performance gains that range between moderate and significant for the various considered scenarios. Such improvements are attributed to the joint capabilities of SIC and NC in effectively controlling the interference and improving the spatial reuse.

In this paper, we study the performance of multi-hop wireless networks when both proper interference control and effective spatial reuse are jointly considered. For the former, we assume nodes endowed with Successive Interference Cancellation (SIC) capabilities at the physical layer and for the latter, we advocate joint link scheduling and power allocation. We study the achievable performance of such networks through a cross-layer design framework. We formulate the joint problem of routing, link scheduling and power allocation as a mixed integer non-linear program (MINLP) and we use column generation (CG) to decompose and linearize it, and hence, solve it. Our numerical results show that when SIC and power control are combined, around 75% performance improvement in dense networks may be achieved in comparison with a network that does not incorporate any advanced interference management techniques.

In this work a cross-layer optimization in centralized Wireless Mesh Networks equipped with multiple antennas is introduced. A scenario has been considered in which multiple antennas at each node are employed to suppress the interference through beam-forming. By integrating different constraints from MAC and Network layers, a mathematical LP formulation is presented to minimize the system activation time. Since the optimization problem is a complex combinatorial one, the optimal solution is approached by a Column Generation decomposition method. Numerical results indicating the theoretical capacity limit of the network are provided for different node densities, transmission ranges and number of antennas. It is shown that interference suppression increases the spectrum spatial reuse and enhances the throughput of the network by minimizing the operation time duration of the system. Moreover, depending on the density of the interference and traffic sessions, there is a saturation threshold on the number of antenna elements; beyond that, more antennas do not necessarily result in smaller system activation time. Furthermore, increasing the transmission range leads to decrease the system activation time of such networks.

We present a cross-layer optimization framework for wireless mesh networks; we assume nodes are equipped with smart antenna and techniques such as beam-forming, spatial division multiple access and spatial division multiplexing are considered. These techniques provide interference suppression, capability to communicate with several nodes simultaneously and higher transmission data rates, respectively. By integrating different constraints from MAC and network layers, a mathematical formulation of the problem is presented. It is shown that the resulted directive, multiple access and multiplexing gain combined with optimal link scheduling effectively increase both the spectrum spatial reuse and the capacity of the links and thus, enhance the achievable system throughput. Since the optimization problem is a complex combinatorial one, the optimal LP solution is approached by a Column Generation decomposition method. The numerical results for different network topologies with various node densities, transmission ranges, traffics and number of antennas are provided, in which system activation time is reduced up to 86.9% by employing smart antenna techniques.