An easy approach to understand tech specs
LTE Physical layer also supports an alternative frame structure to transmit data only in TDD mode over the RF link.
In this structure the radio frame is divided into two half-frames. Each half-frame is made up of 7 time slots. First time slot (TS0) in frame must contain DwPTs, pilot information for downlink. Second time Slot (TS1) in frame must contain UpPTs pilot information for Uplink. Also TS0 and TS1 should be separated with guard bands (GP).
LTE alternative frame structure to support TDD is discussed below.
LTE physical (PHY) layer Alternative frame structure for TDD only mode.
Alternative frame structure to support TDD
The the frame standard supports only TDD based transmissions. Parameters of this frame structure is shown below:
Frame Duration = 10 ms or 10/1000000 second.
One Frame has 2 sub-frames or half-frames.
Half-frame duration = 5 ms or 5/1000000 second.
One half-frame has 7 time slots.
One Time slot = 0.667 ms or 0.667/1000000 second.
DwPTs and UpPTs are discussed next
Each slot can itself contain many OFDM symbols. The difference in number of symbols are dependent on the Cyclic Prefix (CP) length.