Multiple division soft pilot reuse in massive MIMO cellular networks

Abstract

Pilot is a limited resource in most wireless communication system including massive Multiple-Input Multiple-Output (MIMO) cellular networks. Facing the rapid increase of wireless users, how to reuse pilot appropriately has become a point of research interest. This paper introduces a new method, named `Multiple Division Soft Pilot Reuse (MD-SPR)', which is a development of classical Soft Pilot Reuse (SPR) method. MD-SPR has a more elaborate way to divide regions for different degrees of pilot reuse, which may apply more than two reuse factors in one cell simultaneously. It is more convenient for MD-SPR to take account of both user capacity and pilot contamination, and make a balanced decision between them. Compared to single-used mode and classical SPR, MD-SPR is able to achieve better performance on SINR, transmission rate, limit of user's quantity, etc. It provides a novel technique to utilize pilot resources more efficiently in future systems. Numerical results from simulation have been obtained to verify the advantages of MD-SPR.