This paper discusses the improvements that uplink MIMO brings to Mobile WiMAX network deployments and introduces a new technique based on uplink MIMO: Tile
Switched Diversity (TSD). Uplink MIMO (UL-MIMO) provides extended coverage, and can also be used to reduce power consumption and greatly ease design constraints for high output power CPEs. Maximum performance is obtained when UL-MIMO is implemented both at the mobile station and the base station, but this analysis shows that significant gains can be
achieved with UL-MIMO implemented at the mobile station only.