ISI Modeling and BER Performance for Rotating Light-Trail Image Sensor Communication

2026-05-17

AI Summary

This work addresses the challenge of modeling and optimizing bit error rate (BER) in rolling-shutter-based optical camera communication systems, where inter-symbol interference (ISI) from adjacent symbols complicates analytical treatment. To overcome this, the authors propose a simplified model that accounts only for nearest-neighbor ISI and derive a closed-form BER expression based on the Q-function. By integrating pixel-value histograms of light trails with probabilistic noise analysis, this approach enables, for the first time, an analytical solution for BER and establishes sufficient conditions for the model’s validity. Using a midpoint threshold decision rule derived from the most error-prone symbol pairs, the proposed model demonstrates excellent agreement with empirical BER measurements in both Monte Carlo simulations and real-world experiments. Furthermore, it facilitates optimal control angle selection to maximize system throughput under a target BER constraint.

Abstract

Image sensor communication (ISC) employing a propeller-LED transmitter encodes data along rotating light trails. We present an analytical framework that (i) constructs a single-LED, single-blink light trail model that maps optical power to pixel values, and (ii) integrates a probabilistic noise model to derive a closed-form bit-error rate (BER) using the $Q$-function. Trimodal pixel-value histograms motivate an adjacent-only inter-symbol interference (ISI) model in which the decision at segment $j$ depends on adjacent segments. Applying a hardest-pair midpoint threshold yields per-segment BER and a general BER after marginalization. We further provide practical sufficiency conditions under which adjacent-only ISI is adequate, and validate its tightness against Monte Carlo simulations and experimental results. Using the analytical BER, we select the control angle that maximizes throughput while satisfying a target BER reliability constraint.

Problem

• image sensor communication
• inter-symbol interference
• bit-error rate
• rotating light-trail
• pixel-value histogram

Innovation

• image sensor communication
• inter-symbol interference (ISI)
• bit-error rate (BER)
• rotating light-trail
• analytical modeling