Fast-Decodable MIMO HARQ Systems

作者：Hosseini Seyyed Saleh^*; Abouei Jamshid; Uysal Murat

来源：IEEE Transactions on Wireless Communications, 2015, 14(5): 2827-2840.

DOI：10.1109/TWC.2015.2395411

• Multi-Input Multi-Output ( MIMO)
• Hybrid Automatic Repeat reQuest (HARQ) systems
• Space-Time Block Codes (STBCs)
• Sphere Decoder (SD) algorithm
• fast-decodable

This paper presents a comprehensive study on the problem of decoding complexity in a Multi-Input Multi-Output (MIMO) Hybrid Automatic Repeat reQuest (HARQ) system based on Space-Time Block Codes (STBCs). We show that there exist two classes of fast-decodable MIMO HARQ systems: independent and dependent STBC structures. For the independent class, two types of protocols namely, fixed and adaptive threshold-based are presented and their effectiveness in both computational complexity reduction and spectral efficiency preservation are discussed. For the dependent class, a fast Sphere Decoder (SD) algorithm with a low computational complexity is proposed for decoding process of HARQ rounds. Two new concepts are introduced to leverage the fast-decodable notion in MIMO HARQ systems. Simulation results show that the proposed fast-decodable MIMO HARQ protocols in both classes provide a significant reduction in the decoding complexity as compared with the original MIMO HARQ method.

• 出版日期2015-5