Tracking bandwidth limitations for strong optical-turbulence conditions

Area of Science:

• Optical engineering
• Adaptive optics systems

Background:

• Beam-control systems are crucial for applications requiring precise light delivery.
• Adaptive optics (AO) compensation is often used to mitigate atmospheric turbulence effects.
• Understanding tracking frequency limitations is essential for optimizing system performance.

Purpose of the Study:

• To derive a modified fundamental tracking frequency for beam-control systems without adaptive optics.
• To determine the optimal tracking bandwidth for such systems.
• To identify the primary factors limiting system performance.

Main Methods:

• Theoretical derivation of a modified fundamental tracking frequency.
• Analysis of system performance as a function of tracking bandwidth.
• Investigation of the relative contributions of beam spreading and beam jitter.

Main Results:

• A modified fundamental tracking frequency was derived.
• Diminishing returns in performance were observed when tracking faster than this frequency.
• Increasing track bandwidth beyond a threshold (when D/r0 > 4) did not improve performance.

Conclusions:

• Beam spreading is the dominant factor limiting performance in these systems, not beam jitter.
• There is an optimal tracking frequency beyond which further increases yield no benefit.
• System performance is limited by factors other than tracking speed when beam spreading is significant.