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4G LTE Downlink generic frame format.
LTE downlink sub-frame for normal cyclic prefix is shown in Figure below. This generic frame format is common to both TDD and FDD access modes. Each downlink sub frame contains.
Frame Duration = 10 ms or 10/1000000 second.
One Frame has 10 sub-frames.
Sub-frame duration = 1 ms or 1/1000000 second.
One Sub-frame has 2 time slots.
One Time slot = .5 ms or 1/2000000 second.
Each Time slot contains 7 OFDM symbols with normal Cyclic Prefix.
Control - PCFICH, PHICH, PDCCH
Reference signal - MIMO Antenna 1
Reference signal - MIMO Antenna 2
Downlink control signaling consists of three physical channels –
(1) Physical Control Format Indicator Channel (PCFICH) to indicate the number of OFDM
symbols used for control,
(2) Physical H-ARQ Indicator Channel (PHICH) which carries downlink ACK/NACK, and
(3) Physical Downlink Control Channel (PDCCH) which carries the scheduling assignments and power control commands.