MSMA-PPG: Channel-Aligned Expert Routing for Selected-Wavelength PPG Prediction

Anonymous (ICLR 2027 double-blind submission)

Summary

Learns from synchronized multi-wavelength PPG and predicts from a single selected PPG stream + acceleration. Shared optical backbone with wavelength-specific projections/adapters, full-to-subset alignment, and a Channel-Aligned Mixture of Experts with availability-masked top-2 routing. With routing disabled: lowest participant-macro HR MAE on EarSet (5.020 bpm) and PPG-DaLiA (9.246 bpm), lowest SBP MAE (15.456 mmHg), second-best AF AUPRC/AUROC (0.5177/0.8909).