LODS-MTI: A Link-Adaptive, 0rthogonal, and De-slotted Protocol for Robust and Fast RFID Missing Tag Identification

Existing Missing Tag Identification (MTI) protocols trade logic-layer scheduling reliability for physical-layer spectral efficiency. This paper presents LODS-MTI, a Link-adaptive Orthogonal De-slotted protocol that eliminates inter-tag guard times using batch-synchronized continuous bitstreams. To mitigate synchronization loss in de-slotted transmissions, a digital majority voting mechanism corrects single-bit timing slips and accommodates 0.4% clock drift. The design uses short-term coherence through "Power-of-2" batching to replace arithmetic division with bitwise operations. A tolerance-driven feedback loop (ε=0.30) adjusts redundancy based on link quality to maintain a Safe Operating Area (SOA) with 99.10% accuracy within 128-bit windows. Experimental results show that LODS-MTI achieves a normalized time efficiency of Γ ≈ 3.52 (a 50% increase over baselines) and sustains 5,200–8,811 tags/s goodput (Pe ≈ 0.1) at 150 μJ/tag, reducing energy consumption by approximately 10× compared to analog collision resolution schemes. Code and results are available at GitHub. ( https://github.com/ZoeLoveHGJ/Project_LODS_MTI ).