Maximal Ratio Sparse Vector Coding for Short Packet Transmission

Abstract

With the proliferation of automated services in recent years, the demand for reliable communication among the devices and machine-human interactions has increased like never before. In general, the amount of information that is exchanged for mission-critical applications is tiny for service categories such as ultra reliable and low latency communication (URLLC) and massive machine-type communications (mMTC). To handle short packet transmission, sparse vector coding (SVC) was recently proposed where the packet information is embedded into the positions of the sparse vector. In this paper, to further improve the performance of SVC in terms of reliability, maximal ratio transmission (MRT) is employed. The distinctive feature of the proposed scheme to that of conventional SVC is that the composite of weighted MRT coefficients with sparse vector is transmitted over the channel. Simulated results under realistic international telecommunication union (ITU) channel models suggest that by exploiting spatial diversity at the transmitter side, the block error rate (BLER) can be reduced with the increased number of antennas. In brief, MRT-aided SVC transmission can be a key enabler for reliable communication and a practical choice for beyond 5G (B5G) communication systems.