A multiple access scheme has been followed for the physical layer that is based on orthogonal frequency division multiplexing (OFDM) for the downlink (DL), and single carrier frequency division multiple access (SC-FDMA) for the uplink (UL). The OFDM in the DL supports high peak data rate and the SC-FDMA in the UL supports relatively lower peak to average power ratio (PAPR), which maximizes power efficiency at the user end. The LTE air interface supports both frequency division duplex (FDD) and time division duplex (TDD) modes.

Channel bandwidths are made selectable from 1.4 MHz to 20 MHz, with a sub-carrier spacing of 15 kHz.