An Enhanced Random Access Scheme: Multi-Power Contention Resolution Diversity Slotted Aloha

Abstract

Recently, the random access (RA) protocols are widely used in modern wireless communication systems. However, message collisions in RA usually cause low channel efficiency and high time delay. In this paper, a novel RA scheme named multi-power contention resolution diversity slotted aloha (MP-CRDSA) is proposed. In MP-CRDSA, the RA packets are transmitted in random power levels and multiple slots. In the receiver, the collisions are solved by iterative successive interference cancellation (SIC). Theoretical analysis and numerical results show that the proposed RA scheme performs high throughput, low packet loss ratio and low time delay, outperforming the ordinary RA scheme.