The LTE time-domain structure in the case of TDD operation is similar to that of FDD with the following exceptions:
LTE time-domain structure TDD
- The 10 ms frame is assumed to consist of two equal-sized half-frames, each of length 5 ms and each consisting of five subframes of length 1 ms.
- The second sub-frame within each half-frame (sub-frame #1 and #6 within the frame) has a special structure. More specifically, it consists of a downlink part (DwPTS), a guard period (GP), and an uplink part (UpPTS). The downlink-to-uplink switching point takes place within the second sub-frame of each half-frame, i.e. there can be two downlink-to-uplink switching points within each frame. The corresponding uplink-to-downlink switching point can take place at any sub-sequent sub-frame boundary within the half-frame. Thus, the first sub-frame of each half frame is always a downlink sub-frame.