IEEE Open Journal of the Communications Society

LoRa-PRIME: A Novel Secret Key Generation Framework Based on Periodic Bit Reversal and Modified Adaptive Quantization for Robust Cooperative Jamming LoRa Relay Networks

Ida Anisah, Suwadi Suwadi, Wirawan, Mike Yuliana

Published Jan 1, 2026• 2 citations

Abstract

Physical-layer secret key generation (SKG) offers a lightweight security approach for resource-constrained Internet of Things (IoT) devices. However, most existing methods are designed for direct links and do not explicitly address relay-assisted LoRa networks. This paper presents LoRa-PRIME, an SKG framework that combines channel probing, Savitzky–Golay preprocessing, modified Adaptive Dual-Threshold Quantization (ADQ), Bose–Chaudhuri–Hocquenghem (BCH) reconciliation, Periodic Reversal for Keying (PRK) randomness enhancement, and SHA-256 privacy amplification. Experiments were conducted using real LoRa devices under indoor line-of-sight (LOS), indoor non-LOS, and outdoor non-LOS conditions. Savitzky–Golay filtering increased channel correlation (e.g., from 0.7595 to 0.8443 in indoor LOS), supporting reliable key extraction. The 4-bit modified ADQ achieved higher key agreement rates (up to 0.9745) and key generation rates (up to 33.04 bps) compared with Sky-Glow, while reducing key generation time to 7.75 s/key. PRK improved randomness quality, increasing the number of NIST-compliant keys from 4 to 14 in indoor LOS and showing similar improvements in other environments. Complexity analysis indicates approximately linear O(N)scalability, with more than 85% of execution time dominated by channel probing, while signal processing and cryptographic stages introduce minimal overhead. The measured energy consumption is 6.619 J per key, lower than several reported LoRa-based SKG implementations. These results suggest that LoRa-PRIME provides an efficient and practical SKG solution for relay-assisted LoRa IoT deployments.

DOI: 10.1109/ojcoms.2026.3672889

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