CLARQ: A Dynamic ARQ Solution for Ultra-High Closed-Loop Reliability

IEEE Transactions on Wireless Communications, vol. 21, pp. 280–294

Abstract

Emerging wireless control applications demand for extremely high closed-loop reliability under strict latency constraints, which the conventional Automatic Repeat reQuest (ARQ) solutions with static schedules fail to provide. To overcome this issue and enable data-link layer error control for ultra reliable low-latency communication (URLLC) services, we propose a novel protocol: the Closed-Loop ARQ (CLARQ), which forces to accomplish an information exchange round within a fixed loop-back latency, and dynamically re-allocates the remaining resource between uplink and downlink slots upon the result of last uplink transmission. The proposed method guarantees to meet the latency requirement, while delivering high communication reliability and power efficiency. It can be efficiently offline optimized by means of dynamic programming techniques, and is capable of real-time deployment with a low-cost implementation based on look-up tables. Numerical evaluations have verified that CLARQ outperforms baselines with significantly improved closed-loop reliability and reduced energy consumption. Especially, over a Rayleigh channel with 0 dB mean SNR, it is able to provide a closed-loop error rate below 10−7within 10 ms loop-back latency, which makes our proposal competitive for practical URLLC applications in future 5G-and-beyond networks.

Authors 6

1. Bin Han

   University of Kaiserslautern

   Affiliation as printed

   Division of Wireless Communications and Radio Positioning (WiCoN), University of Kaiserslautern, Kaiserslautern, Germany

   [Division of Wireless Communications and Radio Positioning (Wi Co N), University of Kaiserslautern, 67663 Kaiserslautern, Germany. (e-mail: binhan@eit.uni-kl.de)]

2. Yao Lin Zhu Aachen ISEK Research Area [School of Electronic Information

   Wuhan University · RWTH Aachen University

   Affiliation as printed

   ISEK Research Area, RWTH Aachen University, Aachen, Germany

   School of Electronic Information, Wuhan University, Wuhan, China

   [School of Electronic Information, Wuhan University, 430072 Wuhan, China, and with ISEK Research Area, RWTH Aachen University, D-52074 Aachen. Germany.]

3. Muxia Sun

   Tsinghua University

   Affiliation as printed

   Department of Industrial Engineering, Tsinghua University, Beijing, China

   Department of Industrial Engineering, Tsinghua University, Beijing 100084, CHINA

4. Vincenzo Sciancalepore

   NEC (Germany)

   Affiliation as printed

   NEC Laboratories Europe, Heidelberg, Germany

   [NEC Laboratories Europe, 69115 Heidelberg, Germany.]

5. Yulin Hu Aachen ISEK Research Area [School of Electronic Information

   Wuhan University · RWTH Aachen University

   Affiliation as printed

   ISEK Research Area, RWTH Aachen University, Aachen, Germany

   School of Electronic Information, Wuhan University, Wuhan, China

   [School of Electronic Information, Wuhan University, 430072 Wuhan, China, and with ISEK Research Area, RWTH Aachen University, D-52074 Aachen. Germany.]

6. Hans Dieter Schotten

   University of Kaiserslautern

   Affiliation as printed

   Division of Wireless Communications and Radio Positioning (WiCoN), University of Kaiserslautern, Kaiserslautern, Germany

   [Division of Wireless Communications and Radio Positioning (Wi Co N), University of Kaiserslautern, 67663 Kaiserslautern, Germany.]