Enhanced Link Adaptation for Extended Reality Code Block Group based HARQ Transmissions

Extended Reality (XR) is an umbrella term for augmented, virtual, and mixed reality applications. XR traffic is characterized by high data rates with bounded latency constraints, which is challenging for bandwidth-constrained wireless systems. In this paper, we propose two new low-complexity enhanced Outer Loop Link Adaptation (eOLLA) algorithms to improve the downlink system capacity for satisfied XR users by leveraging usage of Code Block Group (CBG) based Hybrid Automatic Repeat reQuest (HARQ) multi-bit feedback. The proposed eOLLA algorithms control the first and second block error operation points to minimize resource usage. Evaluation by means of analytical assessment and realistic system-level simulations verifies that the proposed eOLLA algorithms result in increased system capacity by up to 67% compared to todays known OLLA algorithms with traditional transport block based HARQ.