—FDD frame structure
—One frame is 10ms and it consists of
10 sub-frames.
—One LTE sub frame is 1ms and contains
2 slots
—One slot is 0.5ms in time domain and
each 0.5ms assignment can contain N resource.
—One resource block is 0.5ms and
contains 12 subcarriers for each OFDM symbol in frequency domain.
—There are 7 symbols (normal cyclic
prefix) per time slot in the time domain or 6 symbols in long cyclic prefix for
LTE.
Cyclic
prefix is nothing but guard timer. It is used to make successful receiving of
OFDM symbol at receiver side. There are two types cyclic prefix has been
introduced in lte namely "Normal cyclic
prefix" and "Extended cyclic prefix". Usually normal cyclic
prefix is sufficient to suppress the multi-path delay spread. But some
places(hilly areas) multi-path delay is significantly high. So to suppress
multi-path delay in hilly area's extended cyclic prefix is being used.
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