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For many wireless ad-hoc network (WANET) applications, including wireless sensor, robotic, and flying ad-hoc networks, area coverage is a major challenge. This challenge, which may include the number of required nodes, cumulative energy consumption, or total distance travelled, involves covering the largest possible area with the least cost. Whatever the scenario and cost functions, efficiently deploying the nodes throughout their entire missions is an important factor. For larger networks, this can best be performed using proper topology formations that are essentially designated geometric graph patterns. As a network topology formation and node deployment strategy, this study presents a unique tree-formed geometric graph pattern. With any given number of nodes, it guarantees the maximum possible combined area coverage. Considering its graph theory and Euclidean characteristics, the pattern is then described as both algebraic and algorithmic relations. The formation is remarkably scalable because it may include an unlimited number of nodes while ensuring connectivity in a tree topology. In addition to presenting a breakdown of multiple features and attributes, including symmetry and fractality, we will make a comparative analysis with six known regular lattices and a line formation. Our analyses then show that MAX-Tree covers up to twice as much area compared to all other regular lattices of the same node cardinalities while being more robust and reliable than a line formation. MAX-Tree can be extremely beneficial for drone networks, smart industry and agriculture applications, ocean-bed monitoring systems, and many other WANET scenarios. [ABSTRACT FROM AUTHOR]

The distributed mobile robotic network consists of a group of mobile nodes, such as mobile sensors, unmanned vehicles, unmanned submarines, unmanned air vehicles, or mobile robots. The mobile robotic network keeping a regular topology can utilize efficient network protocols and is also promising in many application scenarios. We propose a distributed algorithm that controls multiple distributed robotic nodes to form regular topology, including straight line, ring, triangular lattice, and square lattice. Our algorithm generates artificial forces, including the attractive force towards a reference point to gather the distributed nodes, the repulsive force from neighboring nodes to keep the desirable distance among them, the formation force to form a specific shape, and the obstacle avoidance force to avoid possible obstacles, such that each node simply follows the resultant force to move. The algorithm works in a fully distributed manner, converges fast, and is easy to deploy, requiring only one-hop local network geometry information. And, it is effective under both 2D and 3D scenarios. A computer demo is developed to demonstrate the effectiveness of the algorithm for large numbers of robotic nodes. [ABSTRACT FROM AUTHOR]

This paper addresses the throughput optimization problem in multihop ultra-wideband (UWB) networks by jointly considering network topology formation and routing. Given a spatial distribution of UWB devices and traffic requirement, we want to form piconets and select paths to maximize the network throughput. Although there have been several works considering the problem of selecting paths to achieve the optimal throughput in multihop wireless networks, to the best of our knowledge, none of them takes the topology formation into the consideration. In this paper, we use Boolean matrices to model role assignment in UWB networks and formulate the throughput optimization problem as a nonlinear programming (NLP) problem. Since the throughput optimization problem is NP-hard, we give an upper bound of the optimal throughput by relaxing some constraints and using pseudo-Boolean optimization to linearize the NLP. We prove that the solution of the upper bound is at most three times of the optimal throughput. Based on the topology formed by solving the upper bound, we formulate a lower bound of the optimal throughput as a linear programming problem and use column generation to solve the lower bound. Numerical results show that the lower bound is very close to the upper bound. Simulation results demonstrate the effectiveness of the scheme. [ABSTRACT FROM AUTHOR]

This paper proposes a distributed self-healing technique for topology formation in dynamic Bluetooth wireless personal area networks (BT-WPANs) and analyzes three new algorithms for scatternet formation. The three algorithms employ distributed procedures for the insertion of one or more nodes in a BT-WPAN, and are able to effectively compromise between the need for system efficiency and the desire to promptly adapt to topology changes. Depending on which algorithm is employed, the proposed approach generates BT-WPANs with different connectivity properties as well as topology structures. [ABSTRACT FROM PUBLISHER]

We investigate issues that Bluetooth may face in evolving from a simple wire replacement to a large-scale ad hoc networking technology. We do so by examining the efficacy of Bluetooth in establishing a connected topology, which is a basic requirement of any networking technology. We demonstrate that Bluetooth experiences some fundamental algorithmic challenges in accomplishing this seemingly simple task. Specifically, deciding whether there exists at least one connected topology that satisfies the Bluetooth constraints is NP-hard. Several implementation problems also arise due to the internal structure of the Bluetooth protocol stack. All these together degrade the performance of the network, or increase the complexity of operation. Given the availability of efficient substitute technologies, Bluetooth's use may end up being limited to small ad hoc networks. [ABSTRACT FROM AUTHOR]