Connectivity and stretch factor trade-offs in wireless sensor networks with directional antennae

Abstract

We consider the following Antenna Orientation Problem: Given a connected Unit Disk Graph (UDG) formed by n identical omnidirectional sensors, what is the optimal range (or radius) which is necessary and sufficient for a given antenna beamwidth (or angle) φ so that after replacing the omnidirectional sensors by directional antennas of beamwidth φ it is possible to find an appropriate orientation of each antenna so that the resulting graph is strongly connected? In this paper we study beamwidth/range tradeoffs for the Antenna Orientation Problem.Namely, for the full range of angles in the interval [0, 2π ] we compare the antenna range provided by an orientation algorithm to the optimal possible for the given beamwidth. We propose new antenna orientation algorithms that ensure improved bounds for given angle ranges and analyze their complexity. We also examine the Antenna Orientation Problem with Constant Stretch Factor, where we wish to optimize both the transmission range and the hop-stretch factor of the induced communication network. We present approximations to this problem for antennas with angles π /2 ≤ φ ≤ 2π .

The Sound of Communication in Underwater Acoustic Sensor Networks

“…In the symmetric model, communication is possible if the sender and receiver are within the range (determined by respective lobes) of each other, see [1,23]. In the asymmetric model, the sender can transmit directly a message to the receiver (provided the receiver is within the range of the sender) but the receiver may not be able to send directly a message to the sender, see [6,9,17,20]. In a way, the asymmetric model is less rigid than the symmetric one, but the receiver must seek a (alternate) path in the network if it also wants to talk to the sender.…”

“…Thus, to establish bidirectional communication between S, R in the asymmetric communication model not only a path must be found between source S and destination R; in addition, a path must be found in the reverse direction from destination R to source S. Despite this difficulty it is still possible to provide algorithms that can establish bidirectional communication [6,9,17,20] with constant stretch factor.…”

Game of operation of a telecommunication network of agents with directional antennae

“…Другим примером описываемой системы может быть беспроводная сеть, в которой узлы оснащены направленными антеннами, описанная в работе [4] и более поздних работах [1,8,3] и др. Использование направленных антенн обусловлено соображениями энергоэффективности и безопасности.…”