Free-space-optical mobile ad hoc networks: Auto-configurable building blocks

Abstract

Existence of line of sight (LOS) and alignment between the communicating antennas is one of the key requirements for free-space-optical (FSO) communication. To ensure uninterrupted data flow, auto-aligning transmitter and receiver modules are necessary. We propose a new FSO node design that uses spherical surfaces covered with transmitter and receiver modules for maintaining optical links even when nodes are in relative motion. The spherical FSO node provides angular diversity in 3-dimensions, and hence provides an LOS at any orientation as long as there are no obstacles in between the communicating nodes. For proof-of-concept, we designed and tested an auto-configurable circuit, integrated with light sources and detectors placed on spherical surfaces. We demonstrated communication between a stationary and a mobile node using these initial prototypes of such FSO structures. We also performed the necessary theoretical analysis to demonstrate scalability of our FSO node designs to longer distances as well as feasibility of denser packaging of transceivers on such nodes.

AODVH: Ad Hoc On-Demand Distance Vector Routing for Hybrid Nodes

“…Our proposed protocol (AODVH), differs from other multipath routing protocols because it considers hybrid nodes with heterogeneous link characteristics. Bilgi et al [10] and Yuksel et al [11] proposed nodes with FSO links only, and hence differ from our requirements of hybrid nodes.…”

Routing in Optical Mesh Networks - A QoS Perspective

“…Recent studies have indicated to be locum to traditional RF networks [5] for small areas. To cover large distances, free space optics communication technologies use high-powered lasers and expensive components often to offer redundancy to RF networks and some limited spatial reuse of the optical spectrum.…”

Wireless system for monitoring and real-time classification of functional activity

“…2 for the user device at the desktop level. The original idea was to use a honeycombed sphere as proposed by [14]. However, this design is not suitable for us; with tens of LEDs on each face, hundreds of LEDs are required making the size and cost be impractically large if conventional LEDs were used.…”

“…The communication range is a radius of 10 m. We run the simulation 10,000 times for each case with different amount users. The transmission is between two nodes located at (6,10) and (14,10). The obstruction is a wall from (10,4) to (10,16).…”

“…First, the nodes (6,10) and (14,10) are located close to the center of the room and they are not always under the coverage of a host. Therefore, the discussion of the reconnect success ratio between them becomes meaningless.…”