Abstract—This paper presents an exhaustive investigation of latency optimization in 5G Ultra-Reliable Low-Latency Commu- nication (URLLC) systems. The emergence of 5G Ultra-Reliable Low-Latency Communication (URLLC) has revolutionized wire- less systems by enabling mission-critical applications demanding sub-1ms latency with 99.999% reliability. This paper presents a comprehensive analysis of URLLC latency optimization through three key dimensions: mini-slot scheduling, Hybrid Automatic Repeat Request (HARQ) enhan…