In this work, we study how to design uplink transmission with massive machinetype devices in tactile internet, where ultra-short delay and ultra-highreliability are required. To characterize the transmission reliabilityconstraint, we employ a two-state transmission model based on the achievablerate with finite blocklength channel codes. If the channel gain exceeds athreshold, a short packet can be transmitted with a small error probability;otherwise there is a packet loss. To exploit frequency diversity, we assignmultiple subchannels to each active device, from which the device selects asubchannel with channel gain exceeding the threshold for transmission. To showthe total bandwidth required to ensure the reliability, we optimize the numberof subchannels and bandwidth of each subchannel and the threshold for eachdevice to minimize the total bandwidth of the system with a given number ofantennas at the base station. Numerical results show that with 1000 devices inone cell, the required bandwidth of the optimized policy is acceptable even forprevalent cellular systems. Furthermore, we show that by increasing antennas atthe BS, frequency diversity becomes unnecessary, and the required bandwidth isreduced.
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