A Novel Effective DQ-Based Access Protocol with Load Estimation for Massive M2M Communications

This paper proposes a novel effective protocol based on the Distributed Queue (DQ) mechanism to tackle the massive access issue in the cellular-based Machine-to-Machine (M2M) communications. To fully take the advantage of the DQ mechanism, we propose a novel method to avoid the inherent over-division problem by letting the base station first roughly probes the number of colliding devices in a Random Access Opportunity. Based on the probing result, the base station then randomly divides these devices into a determined number of groups and "pushes" these groups to the end of a logical access queue. In addition, we develop an analytical model to accurately estimate the average access delay of the proposed protocol in the massive scenarios. Computer simulations are also performed to validate the correctness of the analytical model as well as the effectiveness of the proposed protocol in comparison with the LTE standard and conventional DQ access schemes.