frequency [ghz]

Frequency [GHz] Time [ns] Measured output v [mV] V(t - ) [mV] Periodic Quasi-periodic Chaotic PSD [dB] V(t) [mV] High Speed Chaos Generated in an Opto- Electronic Oscillator Kristine Callan, Lucas Illing, and Daniel J. Gauthier Duke University, Department of Physics, the Fitzpatrick Center for Photonics and Communication Systems, and the Center for Nonlinear and Complex Systems Durham, North Carolina 27708 USA Possible Applications Observed dynamics •Time-delayed feedback occurs in many systems •Important at high speeds (time it takes signals to propagate through device ~ time scale of fluctuations) •Simple nonlinear devices can show complex dynamics •We report on a single time-delayed chaotic device Outlook Chaotic Transmitter Object Correlator Receiver •Intrusion detection system •Envisioned system would use network of devices that transmit and receive chaotic signals •Dynamics of system incorporates received signals high sensitivity •Complex signals low probability of detection •Chaotic Radar •Current systems use periodic signals to gauge distance to object •Proposed system would send chaotic signal, receive it, and gauge distance from correlation of transmitted and received signal •Dynamics change with change in feedback strength, V Bias , and length of time delay •Observed multistability and hysterisis effects Single chaotic device Optical Signal Electric Signal •Light passes through optical fiber to Mach Zehnder Modulator (MZM) •Nonlinear input/output function of MZM modulates light •Detector converts light intensity to RF signal •Electrical signal amplified and fed back to serve as input for MZM •Antenna could be placed at output to transmit signal Nonlinearity P output / P input V Bias [V] •Characterize single device dynamics •Characterize dynamics of two coupled devices •Model behavior of network of coupled devices Laser Modulator Detector Driver V Bias Coupler Output Nonlinearity d Introduction Support •US Army Research Office (grant #W911NF-05-1-0228) Time delay

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Optical Signal. Electric Signal. High Speed Chaos Generated in an Opto-Electronic Oscillator Kristine Callan, Lucas Illing, and Daniel J. Gauthier Duke University, Department of Physics, the Fitzpatrick Center for Photonics and Communication Systems, - PowerPoint PPT Presentation

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Frequency [GHz]

Time [ns]

Mea

sure

d ou

tput

v [

(t -

)

[mV

]

Periodic Quasi-periodic Chaotic

[dB

]V(t) [mV]

High Speed Chaos Generated in an Opto-Electronic OscillatorKristine Callan, Lucas Illing, and Daniel J. GauthierDuke University, Department of Physics, the Fitzpatrick Center for Photonics and Communication Systems, and the Center for Nonlinear and Complex Systems Durham, North Carolina 27708 USA

Possible Applications

Observed dynamics

•Time-delayed feedback occurs in many systems •Important at high speeds (time it takes signals to propagate through device ~ time scale of fluctuations)•Simple nonlinear devices can show complex dynamics•We report on a single time-delayed chaotic device

Outlook

Chaotic Transmitter

Object

Correlator

Receiver

•Intrusion detection system•Envisioned system would use network of devices that transmit and receive chaotic signals•Dynamics of system incorporates received signals high sensitivity •Complex signals low probability of detection

•Chaotic Radar•Current systems use periodic signals to gauge distance to object•Proposed system would send chaotic signal, receive it, and gauge distance from correlation of transmitted and received signal

•Dynamics change with change in feedback strength, VBias, and length of time delay

•Observed multistability and hysterisis effects

Single chaotic device

Optical Signal

Electric Signal

•Light passes through optical fiber to Mach Zehnder Modulator (MZM)

•Nonlinear input/output function of MZM modulates light

•Detector converts light intensity to RF signal

•Electrical signal amplified and fed back to serve as input for MZM

•Antenna could be placed at output to transmit signal

Nonlinearity

Pou