( ) E-UTRAN OFDM 4-, 16- 64-. 20 1200.
E-UTRAN UTRAN Ts = 1/(15000×2048)c. 10 , 307200 Ts. 20 15360×Ts = 0,5, 0 19. 1 10 , 0 9 .2.8. 2 : 1 (FDD) 2 (TDD). . 2.9. FDD TDD.
.2.8. LTE
.2.9.
(UL) (DL) . (D), (U). , () (S), : DwPTS , UpPTS (GP). LTE 7 (.2.10).
.2.10.
DwPTS UpPTS, DL:UL . 2.10 .
LTE . 2.10. , , , . LTE 1900 3800 [1, . 3.2], , .
∆F = 15 OFDM- 1/∆F ≈ 66,7 . ( 0,5) 6 7 OFDM- (cyclic prefix) ‒ . TCP 160s ≈5,2 144s ≈4,7 . 512 s ≈16,7. 6-OFDM (.2.11).
(). 12 , 180 (7 6 OFDM- 0,5 ). OFDM- (); 2 {k,l}, k , l ‒ . , eNB UE, 12×7 = 84 (reference) (.2.12). .
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.2.11.
- . (CRS Cell-specific Reference Signals) . . CRS eNB 4 .2.13. LTE . , R0, 0, R1 1, R2 2, R3 3. ( ) - . 2.1.
.2.12.
.2.13.
2.1
1 . | 4,76 | 5,56 |
2 . | 9,52 | 11,11 |
4 . | 14,29 | 15,87 |
(12 180 ), 1 7 6 OFDM- . (User) .2.14.
.2.14.
OFDM, . , - , - OFDM. OFDM () (), OFDM (. 2.15). -OFDM SC-FDMA (Single Carrier-Frequency Division Multiple Access). .
.2.15. -OFDM
{ } MSC, MSC (, 5 MSC = 12×5 = 60). MSC [9]
zk MSC .{ a0aM-1 }. OFDM-. OFDM- , . - OFDM- - .
SC-FDMA , , (. 2.16.). , SC-FDMA .
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.2.16. DFTS-OFDM
E-UTRA 6 (.2.2). , UE (measurement bandwidth [10]).
2.2
() | 1,4 | |||||
() | 1,08 | 2,7 | 4,5 | 13,5 |