TURBO LDPC

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李赖
9 years ago
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2 TURBO LDPC

3 --- / / /

4 (dbm) d

6 2 2

7 d>>dc dc

8 ---

10 f2-f1 >> Bc

11 RAKE ARQ

12 α 1 α 2 α 3 α M

13 Selective Combining SNR Equal-Gain Combining maximal Ratio Combining SNR

15 P b M = M = 2 M = γ b, SNR/bit, db M = 1 P out log 1 ( ) M = 2

16 1 SNR 10dB SNR M

18 DSSS / RAKE

19 DSSS DSSS + / RAKE Bs>>Bc

20 Bluetooth MHz 1Ms/s IEEE FHSS 2.5 GSM

21 GSM

22 FDD

23 OTD TSTD Time Switched Transmit Diversity STTD Space Time block coding based Transmit Diversity STTD

24 cdma2000 OTD

25 OTD

26 TSTD WCDMA SCH PSC SSC cdma2000 Walsh PN

27 WCDMA STTD b0 b1 b2 b3 1 b0 b1 b2 b3 STTD -b2 b3 b0 -b1 2 STTD P-CCPCH S- CCPCH DPCH PICH PDSCH AICH CPICH

28 STTD STTD 1 STTD 2 TPC TFCI STTD

29 cdma2000 STTD

30 1 WCDMA TPC TFCI w1 2 w2 DPCCH (FBI )

31 WCDMA Bits

32 WCDMA 2 Bit 4 4 Bits 3 Bits 8 1 Bit

33 cdma2000 STD TXAA WCDMA 2 Walsh

34 TURBO LDPC

36 n, k k n n-k k BCH Fire RS n, k, m k n n k m l = m+1 GSM IS-95 TURBO

38 1 [ ] 1 + x + x 3 [1 1 1] 1 + x + x 2

39 2 Conv ( [ ], [1 1 1] ) = (1 + x + x 3 )(1 + x + x 2 ) = 1 + x + x 2 x + x 2 + x 3 x 3 + x 4 + x x + 2x 2 +2x 3 +x 4 + x 5 [ mod-2 ] 1 + x 4 + x 5. [ ]

40 k bits, n-bits 3 Conv( [ ], [1 1 1] ) = [ ] k/n = 1 k/n = 1/2

41 4 [1 0 1]* Conv( [ ], [1 0 1] ) = [ ] [ ] [1 1 1], [1 0 1] ½ known good

42 bit m+1 bits m =

43 ? [ ] [ ] LUT

44 00 [ ] [ ]

45 Viterbi + = Viterbi

46 Viterbi

47 Viterbi /

48 Viterbi /

49 Viterbi /

50 Viterbi /

51 Viterbi /

52 Viterbi /

53 Viterbi /00 00

54 Viterbi [ ] k 00

56 Viterbi 0 inf inf inf Viterbi 00

57 Viterbi 0 inf inf inf h(11, 00) = 2 h(11, 11) = inf inf max(2,0) !

58 inf 11 inf 01 inf 2 0 inf inf

59 inf inf inf 2 0 inf inf

60 inf inf inf inf inf

61 2,1,2 5,7

62 d free d min d free <(5.8)*m m=

63 2,1, ,7 [1 0 1] [1 1 1] d free 5

64 E b /N 0

65 Viterbi Viterbi bits

66 Viterbi 1967 Pe Pe BSC DMC 1.5~2dB

68 ,5,9,2,6,10,3,7, 11,4,8,12 1, 2,3,4,5, 6,7,8, 9, 10,11, ,5,9, 2, 6,10,3,7,11, 4,8,12 f D = 10 Hz, = 10 Mb/s, = 330,000 bits

69 P b Turbo

70 ICC 93 C. Berrou Turbo

71 Turbo Turbo

72 RSC U X X U

73 Turbo ( Z ) 0 = 0 ( X) 0 ( Y) 0 ( ˆd ) ( ) 1 ˆd 2 ( Z) 1 ( X) 1 ( Y) 1 ( Z) 2 ( X) 2 ( Y) 2 L L L ( Z) P 1 ( X) P 1 ( Y) P 1 ( dˆ ) P

74 Turbo MAP ( Z ) 2 k p 1 (y ) 1 k p 1 Z 1k L 1k (y ) 2 k p 1 L 2k ( Z 2k ) p d (x ) 1 k p 1 (y 2k ) p (x 1k ) p (y 1k ) p

75 Turbo

76 Berrou 0.5-1dB

77 Uniform random reverse berrou 10-3 BER Eb/N0(dB)

78 RSC helical 0.5dB

79 Helical Berrou Reverse 10-3 BER Eb/N0(dB)

80 Turbo Turbo

81 Turbo EGCfad EGCconv 10-2 BER Eb/N0(dB)

82 Turbo MRCconv MRCnew BER

83 AWGN Turbo Turbo Turbo

84 LDPC Gallager Low Density Parity Check Code LDPC Zyablov Pinsker 1982 Margulis 1981 Tanner

85 LDPC Turbo LDPC MacKay Neal Spiser Spielman LDPC LDPC LDPC LDPC LDPC

86 LDPC 1 LDPC 0 j 0 k 0 j 3 0 LDPC 0 1 GF(q) 0 q-1

87 LDPC 2 Gallager n j,k LDPC j 1 1 i 1 i- 1 k+1 ik 1 2 MacKay 2 Tanner

88 LDPC 3 LDPC LDPC Tanner 6 LDPC LDPC 4 0

89 LDPC LDPC Gallager BP Sipser Spielman

90 LDPC

論文封面格式

論文封面格式中華大學碩士論文設計一個結構化的低密度同位元檢查碼使能有較大周長及改進錯誤率平緩之現象 Design of Structured LDPC Codes with Large Girth and Low Error Floor 系所別 : 資訊工程系碩士班學號姓名 :M09702038 董致