The 3rd Generation Partnership Project (3GPP) in March 2015 ended specification of Release 12 (R12) standards which enabled seamless switching between FDD and TD under LTE Advanced, strengthened communication performance of LTE Small Cells and provided preliminary definitions and standards for IoT communications, according to Digitimes Research.
While 3GPP R8 and R9 paved the way for smooth transition from post-3G (HSPA+) to LTE (4G) and R10 defined many 4G standards and R11 enhanced LTE functions, R12 and R13 focused on advancement and extension of LTE functionality based on existing LTE architecture and can be regarded as transition from 4G to 5G, Digitimes Research indicated. 3GPP is expected to start R14 specification of preliminary standards for 5G technology in 2016.
Benefits from application of carrier aggregation (CA) technology to FDD LTE networks are much more than those from such application to TD-LTE networks.