Stability and Throughput of Random Access With CS-Based MUD for MTC

Recently, compressive random access has been considered for machine-type communications (MTC) as it has a potential to support massive connectivity by exploiting the sparsity of device activity. However, its performance limitations are not well studied yet compared with other well-known candidates for MTC, e.g., multichannel ALOHA. In this paper, we investigate the stability of compressive random access with a controlled access probability strategy under ideal conditions, and derive the maximum stable throughput, which shows that the maximum stable throughput of compressive random access is higher than that of multichannel ALOHA by a factor of 2. We also carry out simulations to see the performance of compressive random access under more realistic conditions with low-complexity multiuser detection (MUD) algorithms. Based on analysis and simulation results, we can claim that compressive random access can support more devices than conventional multichannel ALOHA and is well-suited for MTC.