Mr. Navik Agrawal Profile

Navik Agrawal

at Univ of Maryland College Park

SPIE Involvement:

Author

Publications (5)

Proceedings Article | 24 August 2010 Paper

Free space optical sensor network for short-range applications

Navik Agrawal, Stuart Milner, Christopher Davis

Proceedings Volume 7814, 78140E (2010) https://doi.org/10.1117/12.862973

KEYWORDS: Head, Free space optics, Telecommunications, Transmitters, Sensor networks, Control systems, Network architectures, Data communications, Transceivers, Vertical cavity surface emitting lasers

Read Abstract +

Free space optical (FSO) sensor networks using direct line of light (LOS) laser links can provide spatially efficient and physically secure connectivity. The data rates can range from bits/s to hundreds of Mb/s with the complete optical transceiver system consuming power in the tens of mW. These features are advantageous for low-power communication networks over short distances in environments where LOS is available, and where radio frequency connectivity must be avoided because of interference or security problems. The range of links in FSO networks is limited by power requirements and angular coverage. In order for FSO directional networks to provide viable short-range connectivity, the networks must provide signal coverage over a wide field of view and operate with efficient media access protocols to minimize random access times for the independent transmitting nodes within the network. In this paper, the system design of a FSO sensor network is presented. The system includes a network of small, low power (mW), integrated systems, or "motes," that transmit data optically to a central "cluster head," which controls the network traffic of all the motes and can relay data to another cluster head in a series of multi-hops to achieve data communication over longer distances. To provide wide field of view signal coverage, each cluster head is equipped with multiple vertical cavity surface emitting lasers oriented in different directions and controlled to diverge at 10°. To implement the proper media access controls, a properly designed master-slave network connecting multiple motes to a cluster head was developed and implemented. The network can handle multiple access from all motes within each cluster head's field of view, as well as set up a directional network backbone between multiple cluster heads, so that signals collected from a mote can be relayed through other cluster heads, until the signal is delivered to its destination. This paper presents the network architecture and optical communication system hardware of our FSO sensor network, and some experimental performance results of our multiple access protocol attempting to resolve channel contention between 10 motes and a cluster head.

Proceedings Article | 21 August 2009 Paper

Free space optical sensor network for fixed infrastructure sensing

Navik Agrawal, Stuart Milner, Christopher Davis

Proceedings Volume 7464, 74640F (2009) https://doi.org/10.1117/12.828124

KEYWORDS: Free space optics, Sensor networks, Transmitters, Head, Prototyping, Vertical cavity surface emitting lasers, Control systems, Signal detection, Photodiodes, Data transmission

Read Abstract +

Proceedings Article | 21 August 2009 Paper

Channel modeling for FSO communications and sensor networking inside structures

Christopher Davis, Mohammed Eslami, Navik Agrawal

Proceedings Volume 7464, 74640G (2009) https://doi.org/10.1117/12.828127

KEYWORDS: Free space optics, Receivers, Sensors, Reflection, Sensor networks, Photons, Monte Carlo methods, Light, Solids, Absorption

Read Abstract +

Proceedings Article | 12 August 2009 Paper

A new technique for probing length scales in clear air

Christopher Davis, Joseph Harris, Robert Gammon

Proceedings Volume 7463, 746306 (2009) https://doi.org/10.1117/12.828126

KEYWORDS: Sensors, Turbulence, Correlation function, Light scattering, Scattering, Atmospheric propagation, Scintillation, Fluid dynamics, Multiple scattering, Signal detection

Read Abstract +

Proceedings Article | 19 August 2008 Paper

Design of free space optical omnidirectional transceivers for indoor applications using non-imaging optical devices

Navik Agrawal, Christopher Davis

Proceedings Volume 7091, 709107 (2008) https://doi.org/10.1117/12.798172

KEYWORDS: Compound parabolic concentrators, Receivers, Transceivers, Transmitters, Photodiodes, Free space optics, Free space, Optical components, Interfaces, Solar concentrators

Read Abstract +

View contact details

UPDATE YOUR PROFILE

Is this your profile? Update it now.

Sign into your SPIE.org account

Don’t have a profile and want one?

Create an account on SPIE.org

Keywords/Phrases

Search In:

Publication Years