A user-pairing based resource allocation scheme for a large number of devices in M2M communications

Machine-to-machine (M2M) communications exhibit quite different characteristics, compared with human-to-human (H2H) communications. Since the number of M2M devices is much larger than that of users for H2H communications, it may cause a shortage problem of radio resources if we do not consider an efficient radio resource management scheme. In this paper, we propose an efficient resource allocation scheme to support a large number of M2M devices in the network. First, we investigate the tradeoff relationship between a non-orthogonal resource allocation scheme based on user-pairing and an orthogonal resource allocation scheme by considering pilot overhead in resource usage. Second, we set up an optimization problem for minimizing the amount of allocated resources for a large number of devices in the network. Finally, we propose a user-pairing based resource allocation algorithm. When the number of devices is 500 and the average SNR is set to 10 dB, our proposed suboptimal minimum resource allocation (SMRA) scheme reduces the total required number of resource blocks by 29% and 28%, compared with the orthogonal resource allocation (ORA) scheme and the random user-pairing based resource allocation (RUPRA) scheme, respectively.