Compressive sensing based random access for machine type communications considering tradeoff between link performance and latency

Machine type communications (MTC) in the next generation of mobile communication systems require a new random access scheme to handle massive access with low signaling overhead and latency. The recently developed compressive sensing multi-user detection (CS-MUD) supports joint activity and data detection by exploiting the sparsity of device activity. In this paper, we adopt the CS-based random access scheme by assigning the unique identification sequences to distinguish the different sensor nodes and employ group orthogonal matching pursuit least square (GOMP-LS) and weighted iteration (WI) GOMP algorithms based on the conventional GOMP with respect to high-reliability and low-latency applications. In addition, to further reduce computational complexity and latency, we introduce a low complexity WIGOMP with inverse Cholesky factorization (WIGOMP-ICF). Based on the simulation results and analysis, we can observe that the proposed three algorithms are promising to support different services requirements for MTC by considering high reliability, low latency, and computational complexity.