LTE may use Orthogonal Frequency Division Multiplexing (OFDM) in the DL and Discrete Fourier Transform (DFT)-spread OFDM, also referred to as Single-Carrier Frequency Division Multiple-Access (SC-FDMA), in the UL. The basic LTE DL physical resource may thus be seen as a time-frequency grid as illustrated in FIG. 1, where each resource element corresponds to one OFDM subcarrier during one OFDM symbol interval. The UL subframe may have the same subcarrier spacing as the DL, and the same number of SC-FDMA symbols in the time domain as OFDM symbols in the DL. The subcarrier spacing has been chosen to be 15 kiloHertz (kHz), as shown. Each resource element may comprise a so-called cyclic prefix, which is involved in preventing inter-symbol interference.

In the time domain, LTE DL transmissions are organized into radio frames of 10 milliseconds (ms), each radio frame consisting of ten equally-sized subframes of length Tsubframe=1 ms as shown in FIG. 2, which illustrates the LTE time-domain structure. Each subframe comprises two slots of duration 0.5 ms each, and the slot numbering within a frame may range from 0 to 19. For normal cyclic prefix, one subframe may consist of 14 OFDM symbols. The duration of each symbol is approximately 71.4 microseconds (μs).

Furthermore, the resource allocation in LTE may typically be described in terms of resource blocks, where a resource block corresponds to one slot, 0.5 ms, in the time domain and 12 contiguous subcarriers in the frequency domain. A pair of two adjacent resource blocks in the time direction, 1.0 ms, may be known as a resource block pair. Resource blocks may be numbered in the frequency domain, starting with 0 from one end of the system bandwidth.