IEEE 2002

I. Introduction:

Wireless optical (infrared) link provides a secure and a promising alternative to radio for indoor wireless applications. The large spectrum of unregulated band enables a link to provide broadband access needed for multimedia and other bandwidth-demanding applications. The spatial confinement of infrared light provides interference-free bandwidth-reuse in adjacent rooms.

This poster highlights some of the research conducted within CICTR to advance optical wireless technology.

II. Motivation

VIII. Conclusions

Broadband Indoor Optical Wireless Communications

Yazan A. Alqudah and Mohsen Kavehrad

Center for Information and Communications Technology Research(CICTR)

The Pennsylvania State University, University Park, PA 16802, USA

•Abundance of unregulated bandwidth, freedom from FCC licensing (2 THz in the 700-1500 nm)

•Spatial confinement (Security and bandwidth reuse)

•No multipath fading (for receiver movements in IM/DD)

•Immunity to radio interference(Reliability)

•Coexistence with radio frequency links

•Ambient light (Limit range)

•Multipath dispersion (Transmission rate limitation)

•Shadowing (Occasional service interruptions)

•Power budget constraints

V. Configurations

Current

Proposed

s(t)

detector

s(t)+

r(t)+n(t)

r(t)=Rs(t)

n(t): Gaussian noise

VI. Intensity Modulation and Direct Detection

VII. Our Research

A. Efficient Environment Characterization

IV. Optical Wireless Link Characteristics

IX. Publications

V. More Information ?

Window

Diffusing spot

Tungsten Lamp

Transmitter

Receiver

B. Link Design:

Equal Gain Combining

Maximal Ratio Combining

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•Data modulates light intensity (always positive)

•Propagation Model: no phase component

•Transmitted power constraint (eye safety considerations)

•Shot noise is caused by Ambient light

•Y. A. Alqudah, M. Kavehrad (FIEEE), “Assessing Feasibility of a New Diffused Configuration for Broadband Wireless Infrared Links,” WCNC 2003, New Orleans, Louisiana.

•Y. A. Alqudah, M. Kavehrad (FIEEE), “On Optimum Order of Angle Diversity with Equal-Gain Combining Receivers for Broadband Indoor Wireless Infrared Communications,” accepted, IEEE Transactions on Vehicular Technology.

•Y. A. Alqudah, M. Kavehrad (FIEEE), “MIMO Characterization of Indoor Wireless Optical Link using Diffused Configuration,” accepted, IEEE Transactions on Communications.

•Y. A. Alqudah, M. Kavehrad (FIEEE), “On Merits of Spatial Coding in Multilevel Wireless Infrared Links ,” submitted, Globecom 2003 -Wireless Communications .

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•S. Jivkova, Y. A. Alqudah, M. Kavehrad (FIEEE), “Optical Wireless Multi-Spot Diffusing Configuration: Link Quality ,” submitted, MILCOM 2003.

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• The optical wireless link provides a promising potential for carrying broadband data in an indoor environment.

• The independence of spatial channels in multi-spot diffusing configuration can be used to further increase the link capacity and reliability.

• New configurations have been evaluated with practical deployment in mind.

• One of our research objectives is to provide ideas that can been utilized by investors, thus bringing technology investments to the region.

C. Spatial Coding