Non-Orthogonal Random Access (NORA) in Large Cellular Networks

Non-orthogonal random access (NORA) is promising to alleviate random access (RA) collision and increase RA throughout. However, the application of NORA in multi-cell scenarios is challenging due to uncertain spatial distribution of NORA UEs and complex inter-cell interference. In this letter, an analytical framework for NORA in multi-cell scenarios is proposed using stochastic geometry. In particular, the approximate spatial distributions of NORA UEs are given. The analytical model of NORA gain is derived taking into account inter-cell interference. Analytical and simulation results indicate the preferred power control scheme and demonstrate that the base station (BS) deployment scheme should be adjusted according to given wireless channel characteristics.