This paper presents a novel radio-resource scheduler with a hardware accelerator for coordinated scheduling in 5G ultra-high-density distributed antenna systems. In 5G mobile communications systems, the transmission weight and the overall system throughputs for a huge number of possible combinations of antennas and user equipment have to be computed. To accelerate the scheduling, the new scheduler executes the computation using dedicated hardware. Moreover, it reduces the computational complexity. Experimental results show that the scheduler performs the computation 126 times faster than without acceleration. Simulated results reveal that the scheduler is able to find an optimal combination that achieves the higher system throughput even in a system with a large number of antennas and user equipment. The new scheduler enables a future practical 5G system.