A study of connectivity in MIMO fading ad-hoc networks

Abstract

Abstract-We investigate the connectivity of fading wireless ad-hoc networks with a pair of novel connectivity metrics. Our first metric looks at the problem of connectivity relying on the outage capacity of MIMO channels. Our second metric relies on a probabilistic treatment of the symbol error rates for such channels. We relate both capacity and symbol error rates to the characteristics of the underlying communication system such as antenna configuration, modulation, coding, and signal strength measured in terms of Signal-to-Interference-Noise-Ratio (SIN R). For each metric of connectivity, we also provide a simplified treatment in the case of ergodic fading channels. In each case, we assume a pair of nodes are connected if their bi-directional measure of connectivity is better than a given threshold. Our analysis relies on the central limit theorem to approximate the distribution of the combined undesired signal affecting each link of an ad-hoc network as Gaussian. Supported by our simulation results, our analysis shows that (1) a measure of connectivity purely based on signal strength is not capable of accurately capturing the connectivity phenomenon, and (2) employing multiple antenna mobile nodes improves the connectivity of fading ad-hoc networks.

Movement-Efficient Sensor Deployment in Wireless Sensor Networks With Limited Communication Range

“…In this section, we extend the proposed algorithms, CCML and DCML, to other kinds of sensing tasks: area coverage and target coverage. We employ the binary coverage model [1]- [15] in which Sensor n can only detect the points within its sensing range r n . Intuitively, in order to decrease the sensing uncertainty, CCML and DCML deploy sensors into high-density regions, and thus the points with high density are more likely to be covered.…”

“…But, the connectivity is still a challenge in MWSNs where sensors are communicating with each other through wireless channels. A common communication model [3], [13]- [15] assumes that each sensor node is able to communicate with sensors in a limited communication range R c . Energy efficiency is another key issue in MWSNs, as most sensors have limited battery energy, and it is inconvenient or even infeasible to replenish the batteries of numerous densely deployed sensors [21].…”

Interference-Aware Scheduling for Connectivity in MIMO Ad Hoc Multicast Networks

“…The impact of fading on network connectivity has been addressed in [13]- [16]. Of particular interest to this paper is [13], which showed that multiple antennas can significantly reduce the node isolation probability in an interference-free network, and [16], whose simulation results demonstrated that multiple antennas can significantly enhance the connectivity of an ad hoc network, measured as the number of links that meet a given requirement on the outage capacity, or the symbol error rate of orthogonal space-time block coding. Interference aspects of the problem have been studied in [17], which investigated the connectivity of sensor networks with regular topologies.…”

A New MAC Protocol for Moving Target in Distributed Wireless Sensor Networks

“…BI frame includes the velocity of mobile node, the ID of mobile node and several sensing parameters collected by mobile node. After the velocity of mobile node (the velocity value can be gained by RF Doppler Shifts [15]) is received by stationary node, it would be compared with VT (Velocity Threshold) which is set before the stage of establishing network, if the two values are different; changing the ST value defined in the sleeping mechanism to adjust the node's sleeping time. In order to make the stationary node adjust its scheduling mechanism in advance, we apply power control technology to increase the mobile node's transmit power for enlarging its communication radius.…”