What is LTE OFDM?

One of the LTE features introduced in Rel-12 is the support for higher order modulation , that is 256QAM for DL data transmission to enhance the spectral efficiency and the system throughput.

Orthogonal Frequency Division Multiplexing (OFDM) is an efficient modulation format used in modern wireless communication systems including 5G.

LTE is based on Orthogonal Frequency Division Multiplexing (OFDM) with cyclic prefix (CP) in the downlink, and on Single-Carrier Frequency Division Multiple Access (SC-FDMA) with cyclic prefix in the uplink. It supports both FDD and TDD duplex modes for transmission on paired and unpaired spectrum.

LTE devices use QPSK, 16QAM and 64QAM to modulate data and control information. The eNodeB supports all of these modulation techniques for the Down Link direction.