Lets discuss the LTE frame structure. Depending upon TDD/FDD , there are two types of frame structures.
Frame structure 1 :
Let me start with FDD, as I am more familiar with FDD systems and yet to work on any TDD system
Smallest slot here is called as Tslot = 15360Tb = 0.5ms. Two consecutive slot is a subframe. Each slot has some OFDM symbols and cyclic prefixes.Every frame will have 10 subframes i.e 10ms.
The diagram shows one frame structure. In these systems , the uplink and downlink systems are separated in the frequency domain each with 10 sub frames.
Every slot will have 6 symbols in case of Normal cyclic prefixes and 5 in case of extended cyclic prefixes.
Frame Structure 2 :
Here is frame is 10ms and consists of two sub frames of 5ms each. These 5ms subframes are further divided into smaller frames of 1ms. Each of these smaller sub frames have three fields.
Every subframe will have following fields.
a. DwPTS - Downlink Pilot TimeSlot - Normal downlink channel with 3-12 OFDM symbols.
b. UpPTS - Uplink Pilot TimeSlot - Normal uplink channel with 1 or 2 OFDM sysmbols.
c. GP Field - Guard Period - It has remaining symbols!
Frame structure 1 :
Let me start with FDD, as I am more familiar with FDD systems and yet to work on any TDD system
Smallest slot here is called as Tslot = 15360Tb = 0.5ms. Two consecutive slot is a subframe. Each slot has some OFDM symbols and cyclic prefixes.Every frame will have 10 subframes i.e 10ms.
The diagram shows one frame structure. In these systems , the uplink and downlink systems are separated in the frequency domain each with 10 sub frames.
Every slot will have 6 symbols in case of Normal cyclic prefixes and 5 in case of extended cyclic prefixes.
Frame Structure 2 :
Here is frame is 10ms and consists of two sub frames of 5ms each. These 5ms subframes are further divided into smaller frames of 1ms. Each of these smaller sub frames have three fields.
Every subframe will have following fields.
a. DwPTS - Downlink Pilot TimeSlot - Normal downlink channel with 3-12 OFDM symbols.
b. UpPTS - Uplink Pilot TimeSlot - Normal uplink channel with 1 or 2 OFDM sysmbols.
c. GP Field - Guard Period - It has remaining symbols!
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