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CITRUS thesis · Wearable PPG/BVP
Motion-robust wearable heart-rate streams
CITRUS studies why ring PPG/BVP heart-rate monitoring fails under motion, then decomposes the deployed stream into candidate disambiguation, causal decoding, reliability estimation, and accept / hold / reject reporting.
- Candidate-based HR estimation rather than direct scalar regression.
- Causal Viterbi decoding using current and past windows only.
- Reliability-aware reporting for coverage-error trade-offs.
Experimental architecture and comparison roles
CITRUS
RingDatasetV2
primary benchmark
PPG-DaLiA
external wrist-BVP validation
Sports cohort
high-motion boundary
MMPD / rPPG
cross-modality boundary
Layer 1
DSP candidates
Layer 2
CITRUS scorer
Layer 3
Causal Viterbi
Layer 4
Reliability layer
Layer 5
Accept / hold / reject
Candidate selection replaces direct scalar regression for corrupted PPG/BVP windows.
Causal decoding uses current and past windows for real-time deployment.
Reliability reporting separates full-coverage error from usable emitted streams.
- 54
- participants
- 49.76 h
- ring recordings
- 10.91 BPM
- motion MAE
- 0.898
- error-risk AUC

