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Related Experiment Video

Updated: Feb 2, 2026

Control of Eating Behavior Using a Novel Feedback System

Control of Eating Behavior Using a Novel Feedback System

Published on: May 8, 2018

Feedback control for microring weight banks.

Alexander N Tait, Hasitha Jayatilleka, Thomas Ferreira De Lima

|November 25, 2018

Summary

This summary is machine-generated.

This study demonstrates continuous, multi-channel control of microring filter banks for analog photonic signal processing. The novel feedback method achieves high accuracy without direct transmission measurements, enabling reconfigurable photonic networks.

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Last Updated: Feb 2, 2026

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Area of Science:

Photonics
Analog Signal Processing
Optical Engineering

Background:

Microring resonators are key for reconfigurable photonic analog signal processing.
Controlling microring filter response is challenging due to fabrication variations and thermal sensitivity.
Previous methods used calibration, feedforward control, or resonance locking via feedback.

Purpose of the Study:

To demonstrate continuous, multi-channel control of a microring weight bank.
To develop a feedback control method relying on estimated filter transmission versus photo-induced resistance changes.
To characterize the performance of this control method under various conditions.

Main Methods:

Implemented a feedback control system for microring weight banks.
Utilized an estimation of filter transmission based on photo-induced resistance changes, avoiding direct transmission measurements.
Characterized the system's response with varying carrier wavelength offset and power.

Main Results:

Achieved continuous, multi-channel control with an effective 5.1 bits of accuracy on 2Gbps signals.
Demonstrated 4.2 bits of accuracy using the estimation method without direct transmission measurements.
Provided detailed characterization of the control response.

Conclusions:

Feedback weight control offers a tractable solution for microring weight banks in reconfigurable analog photonic networks.
The developed estimation-based feedback method enhances control accuracy and robustness.
This work advances the capabilities of high-performance analog signal processing in photonics.