Channel coding over finite transport blocks in modern wireless systems

In modern wireless systems such as 3GPP LTE/LTE-Advanced, packets are partitioned into multiple transport blocks where each transport block is a group of resource elements with a common modulation and coding scheme. Accordingly, a transport block is the data unit in the physical layer of modern wireless systems. In this paper, we investigate the throughput performance of modern wireless systems under channel coding over finite transport blocks. When we apply coding over multiple transport blocks, the underlying wireless channel can be effectively modeled as a finite-state discrete-time Markov chain. We link the characteristics of the underlying physical channel to the parameters of the Markov chain, and derive the corresponding “channel dispersion.” The “channel dispersion” is then used to assess the throughput performance of various communication strategies. The results show that for a fixed packet size the system throughput increases with transport block size.