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We study multi-base station (BS) preamble detection schemes for the narrow-band Internet of Things (NB-IoT) random access by using stochastic geometry analysis. Specifically, we compare the preamble detection performance of two baseline detection schemes: Quantize-and-Forward (QnF) and Detect-and-Forward (DnF). QnF requires the feedback of quantized received power levels while DnF requires 1-bit feedback of local detection result. Our results show that DnF scheme outperforms QnF scheme when the backhaul capacity is limited or when the minimum distance between user and BSs is less than a threshold. Our results also show that the use of multiple collaborative BSs can lead to a significant improvement of the preamble detection performance, as well as reduction of the total power of the preamble transmission.
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This content will become publicly available on June 27, 2026
Low-Latency Preamble-Free Transmission of Short Messages via Quickest Change Detection
The latency and control overhead of sending the preamble in synchronous communications can be excessive when transmitting short sensing/control messages. To reduce these overheads, this work proposes a preamble-free solution based on the framework of quickest change detection. Specific contributions include a joint decoding/demodulation scheme that is provably asymptotically optimal, and a more practical CuSum-like implementation. Numerical results show that the proposed scheme reduces the latency by 47%–79% when compared to the preamble-based solutions. The scheme is also inherently robust and automatically adapts to any unknown underlying SNRs.
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- Award ID(s):
- 2309887
- PAR ID:
- 10618854
- Publisher / Repository:
- IEEE
- Date Published:
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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