5A.2.4 64QAM modulation
25.2233GPPRelease 17Spreading and modulation (TDD)TS
The data modulation is performed to the bits from the output of the physical channel mapping procedure. In case of 64QAM, modulation 6 consecutive binary bits are represented by one complex valued data symbol. Each user burst has two data carrying parts, termed data blocks:
(1c)
Nk is the number of symbols per data field for the user k. This number is linked to the spreading factor Qk.
Data block is transmitted before the midamble and data block
after the midamble. Each of the Nk data symbols
; i=1, 2; k=1,…,K; n=1,…,Nk; of equation 1c has the symbol duration
as already given.
The data modulation is 64QAM, thus the data symbols are generated from 6 consecutive data bits from the output of the physical channel mapping procedure in [8]:
(2c)
using the following mapping to complex symbols:
Consecutive binary bit pattern |
complex symbol |
Consecutive binary bit pattern |
complex symbol |
|
|
||
000000 |
|
100000 |
|
000001 |
|
100001 |
|
000010 |
|
100010 |
|
000011 |
|
100011 |
|
000100 |
|
100100 |
|
000101 |
|
100101 |
|
000110 |
|
100110 |
|
000111 |
|
100111 |
|
001000 |
|
101000 |
|
001001 |
|
101001 |
|
001010 |
|
101010 |
|
001011 |
|
101011 |
|
001100 |
|
101100 |
|
001101 |
|
101101 |
|
001110 |
|
101110 |
|
001111 |
|
101111 |
|
010000 |
|
110000 |
|
010001 |
|
110001 |
|
010010 |
|
110010 |
|
010011 |
|
110011 |
|
010100 |
|
110100 |
|
010101 |
|
110101 |
|
010110 |
|
110110 |
|
010111 |
|
110111 |
|
011000 |
|
111000 |
|
011001 |
|
111001 |
|
011010 |
|
111010 |
|
011011 |
|
111011 |
|
011100 |
|
111100 |
|
011101 |
|
111101 |
|
011110 |
|
111110 |
|
011111 |
|
111111 |
|
The mapping corresponds to a 64QAM modulation of the interleaved and encoded data bits of the table above and
of equation 2c.