Mobile communication and computing gsm-radio-interface-140720014203-phpapp02.pdf

Mobile communication and computing

1. www.huawei.com
Copyright © 2010 Huawei Technologies Co., Ltd. All rights reserved.
英文
标题
:40-47pt
副
标题
:26-30pt
字体 色
颜
:反白
内部使用字体 :
FrutigerNext LT Medium
外部使用字体 : Arial
中文
标题
:35-47pt
字体:黑体
副
标题
:24-28pt
字体 色
颜
:反白
字体:黑体
细
Um Interface and
Radio Channels

2. Copyright © 2010 Huawei Technologies Co., Ltd. All rights reserved. Page2
Contents
1.Overview
2.Processing of Voice Signal
3.Radio Channel

3. Copyright © 2010 Huawei Technologies Co., Ltd. All rights reserved. Page3
Radio Interface
Another MSC
HLR/AUC
SMC
PSTN
ISDN
OMC
MS
Um
MS
A-bis
BSC
A
BTS
MSC/VLR

4. Copyright © 2010 Huawei Technologies Co., Ltd. All rights reserved. Page4
Communication management (CM)Communication management (CM)
Radio resources management (RR)Radio resources management (RR)
Mobility and security management
(MM)
Mobility and security management
(MM)
Integrated managementIntegrated management
TCH0 TCH1 TCH2 。。SACCH 。。TCH23 IDLTCH0 TCH1 TCH2 。。SACCH 。。TCH23 IDL
Multiframe
Physical link layer (L1)
Data link layer (L2)
Network application layer (L3)
Hierarchical Structure of Um Interface
RACH BCCH AGCH/PCH SDCCH SACCH TCH FACCH
CC, SS, SMS
Use LAPDm Protocol

5. Copyright © 2010 Huawei Technologies Co., Ltd. All rights reserved. Page5
Radio Access Technology
Frequency
T
i
m
e
Power
Frequency
T
i
m
e
Power
Frequency
T
i
m
e
Power
FDMAFDMA
TDMATDMA
CDMACDMA
U
s
e
r

U
s
e
r

U
s
e
r

U
s
e
r

U
s
e
r

U
s
e
r

U
s
e
r

U
s
e
r

Time
FDMA
Frequency
TDMA
Time
Frequency
CDMA
Frequency
Time
Code

6. Copyright © 2010 Huawei Technologies Co., Ltd. All rights reserved. Page6
Contents
1.Overview
2.Processing of Voice Signal
3.Radio Channel

7. Copyright © 2010 Huawei Technologies Co., Ltd. All rights reserved. Page7
Voice Signal Processing
((A/DA/D))
2020 msms
22.8kbit/s22.8kbit/s
13kbit/s13kbit/s8KHz,13bi8KHz,13bi
tt
33.8kbit/s33.8kbit/s
SegmentationSegmentation Speech codingSpeech coding Channel codingChannel coding
InterleavingInterleaving EncryptionEncryption)) Burst formatting ModulationModulation
Transmission
Voice

8. Copyright © 2010 Huawei Technologies Co., Ltd. All rights reserved. Page8
Analog-Digital Conversion

9. Copyright © 2010 Huawei Technologies Co., Ltd. All rights reserved. Page9
Speech Coding
The Enhance Full RateEnhance Full Rate coding mode is called CELP CELP (Code Excited Linear Code Excited Linear
Predictive CodingPredictive Coding)
The Full RateFull Rate coding mode is called RPE-LTPRPE-LTP (Regular Pulse Excited-Long Regular Pulse Excited-Long
Term Prediction). Term Prediction).
The Half RateHalf Rate coding mode is called VCELPVCELP ( (Vector-Sum Excited Linear Vector-Sum Excited Linear
PredictionPrediction))
13kbit/s13kbit/s260 bits(FR)260 bits(FR)
112 bits(HR)112 bits(HR)
244 bits(EFR)244 bits(EFR) 12.2kbit/s12.2kbit/s
5.6kbit/s5.6kbit/s
((A/DA/D))
2020 msms
8KHz,13bi8KHz,13bi
tt
SegmentationSegmentation Speech codingSpeech coding
Voice

10. Copyright © 2010 Huawei Technologies Co., Ltd. All rights reserved. Page10
Channel Coding
13kbit/s13kbit/s260 bits(FR)260 bits(FR)
112 bits(HR)112 bits(HR)
244 bits(EFR)244 bits(EFR) 12.2kbit/s12.2kbit/s
5.6kbit/s5.6kbit/s
((A/DA/D))
2020 msms
8KHz,13bi8KHz,13bi
tt
SegmentationSegmentation Speech codingSpeech coding
Voice
Channel codingChannel coding
22.8kbit/s22.8kbit/s456bits(FR/EFR)456bits(FR/EFR)
228bits(HR)228bits(HR) 11.4kbit/s11.4kbit/s
Block
Coder
1:2
Convolutional
Coder

11. Copyright © 2010 Huawei Technologies Co., Ltd. All rights reserved. Page11
1 2 3 4 5 6 7 8 ... ... 452 453 454 455 4561 2 3 4 5 6 7 8 ... ... 452 453 454 455 456
B
8
16
.
.
.
456
8
16
.
.
.
456
2
10
.
.
.
450
2
10
.
.
.
450
6
14
.
.
.
454
6
14
.
.
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454
1
9
.
.
.
449
1
9
.
.
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449
4
12
.
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452
4
12
.
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452
7
15
.
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455
7
15
.
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455
3
11
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451
3
11
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.
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451
5
13
.
.
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453
5
13
.
.
.
453
.... ....
B0 B1 B2 B3 B4 B5 B6 B7
{A4,B0} {A5,B1} {A6,B2} {A7,B3} {B4,C0} {B5,C1} {B6,C2} {B7,C3}{A4,B0} {A5,B1} {A6,B2} {A7,B3} {B4,C0} {B5,C1} {B6,C2} {B7,C3}
First interleaving:
Second interleaving:
Interleaving

12. Copyright © 2010 Huawei Technologies Co., Ltd. All rights reserved. Page13
Voice Burst
Tail Tail
bitbit
Tail Tail
bitbit
Guard Guard
periodperiodDatDat
aa
DataData Training sequenceTraining sequence
57 encrypted bits57 encrypted bits
33
bitsbits
8.25 bits8.25 bits26 bits26 bits1
33
bitsbits
57 encrypted bits57 encrypted bits 1
((A/DA/D))
2020 msms
22.8kbit/s22.8kbit/s
13kbit/13kbit/
ss8KHz,13bit8KHz,13bit
33.8kbit/33.8kbit/
ss
SegmentationSegmentationSpeech codingSpeech coding Channel codingChannel coding
InterleavingInterleavingEncryptionEncryption)) Burst formatting ModulationModulation
Transmission
Voice

13. Copyright © 2010 Huawei Technologies Co., Ltd. All rights reserved. Page14
Voice Signal Processing
33.8 kbit/s
22.8 kbit/s
13 kbit/s
8 kHz
13 bits
Transmitting part
Receiving part
Speaker
Receiver
Demodulator
Adaptive
Equalization
De-ciphering
De-interleaving
Channel decoding
Speech decoding
D/A-conversion
Transmitter
Modulator
Burst formatting
Ciphering
Interleaving
Channel coding
Speech coding
Segmentation
A/D-conversion
Microphone
13 kbit/s
Transmitting part
Receiving part
Transmitter
Modulator
Burst formatting
Ciphering
Interleaving
Channel coding
D/D-conversion
8 kHz
8 bits
64 kbit/s PCM
Receiver
Demodulator
Adaptive
Equalization
De-ciphering
De-interleaving
Channel Decoding
GSM Network
Mobile equipment

14. Copyright © 2010 Huawei Technologies Co., Ltd. All rights reserved. Page15
Transmission delay t
Transmission delay t
TA
The mobile phone should
send the signal in advance!!
Timing Advance (TA)
TA = 0 to 63
1 bit equivalent to 3.7μs
TS has 156bit
Max coverage = 35Km

15. Copyright © 2010 Huawei Technologies Co., Ltd. All rights reserved. Page16
Frequency Hopping
Frequency
f 0
Frame
f 1
f 2
f 3
f 4
Time

16. Copyright © 2010 Huawei Technologies Co., Ltd. All rights reserved. Page17
Prolong battery life and
reduce interference
DTX
DTX: Discontinuous Transmission

Shut off the transmission at voice intervals;

Only transmit SID frames’

The transcoder at the RX terminal produces comfortable noise.
VAD: Voice Activity Detection

Implemented by the transcoder.
Sub & Full
Measurement

17. Copyright © 2010 Huawei Technologies Co., Ltd. All rights reserved. Page18
Power Control
Prolong battery life
Reduce network interference
Include both uplink power control and downlink power control
Level and quality are taken into account
BSC or BTS is the final adjudicator
BCCH Carrier is not
involved in power control.
Time
Signal level
Target level value:
e.g. -85 dm

18. Copyright © 2010 Huawei Technologies Co., Ltd. All rights reserved. Page19
Contents
1.Overview
2.Processing of Voice Signal
3.Radio Channel

19. Copyright © 2010 Huawei Technologies Co., Ltd. All rights reserved. Page20
Frequency
200kHz
15/26ms
BP
Slot
Time
Frame and Channel

20. Copyright © 2010 Huawei Technologies Co., Ltd. All rights reserved. Page21
32107654321
Physical Channel of Logical Channel
0
different
message
types
Logical channel
Physical Channel
Logical channel
Logical channel
Logical channel
Logical channel
TDMA FRAME
200K
577 ms

21. Copyright © 2010 Huawei Technologies Co., Ltd. All rights reserved. Page22
8bit
41 synchronous
bits
36 encrypted
bits
3bit 68.25bit
Tail bit Tail bit Guard intervalData
Guard interval
3bit 142bit 3bit8.25bit
Tail bit Tail bitData
3bit
39 encrypted
bits
39 encrypted
bits
3bit8.25bit
Tail bit Tail bitGuard intervalDataData
Burst
64 synchronous bits
•Access burst (AB): Used in MS initial access
•Frequency correction burst (FB): Used in frequency synchronization
between MS and BTS
•Synchronous burst (SB): Used in timing synchronization between
MS and BTS
63bit TA come from
here

22. Copyright © 2010 Huawei Technologies Co., Ltd. All rights reserved. Page23
3bit
142 modulation bits 3bit8.25bit
Tail bit Tail bitGuard interval
Burst
3bit 57 encrypted bits 57 encrypted bits 3bit8.25bit
Tail bit Tail bitGuard intervalDataData
26bit1 1
Training sequence
Frame stealing flag
Normal burst (NB)

Used to carry the information of the traffic channel and the control channel
except for RACH
Dummy burst (DB)

Used in transmission of filling frames by BTS at timeslots when there is no
information delivered
Burst rate come from
=156.25/(0.577*8)

23. Copyright © 2010 Huawei Technologies Co., Ltd. All rights reserved. Page24
Broadcast control channel
(BCH)
Control channelCommon control channel
(CCCH)
Voice channel
(TCH)
FCCHSCH BCCH TCH/FAGCH RACH
SDCCH
FACCH
SACCH
TCH/H
PCH
Common channel
(CCH)
Dedicated channel
(DCH)
Logical channel
Logical Channel Type
GSM900 and DCS1800 have the same logical channel category
(system information)

24. Copyright © 2010 Huawei Technologies Co., Ltd. All rights reserved. Page25
FCCH
SCH
BCCH
PCH
AGCH
BCCH
CCCH
Common
Channel
SDCCH
SACCH
FACCH
TCH/F
TCH/H
DCCH
TCH
Dedicated
Channel
Downlink Logical Channel

25. Copyright © 2010 Huawei Technologies Co., Ltd. All rights reserved. Page26
RACH CCCH
Common
channel
SDCCH
SACCH
FACCH
TCH/F
TCH/H
DCCH
TCH
Dedicated
channel
Uplink Logical Channel

26. Copyright © 2010 Huawei Technologies Co., Ltd. All rights reserved. Page27
Use of Logical Channels
FCCH
Allocate signaling channel
Power-on Search for frequency correction burst
Search for synchronous burst
Listen to the system information
Monitor paging message
Send access burst
Set up the call
Allocate voice channel
Conversation
Release the call
Idle mode
SCH
BCCH
PCH
RACH
AGCH
SDCCH
SDCCH
TCH
FACCH
Dedicated mode
Idle mode

27. Copyright © 2010 Huawei Technologies Co., Ltd. All rights reserved. Page28
26-frame multi-frame
TCH/F+FACCH/F+SACCH/F (full-rate TCH)
TCH/H+FACCH/H+SACCH/H (half-rate TCH)
51-frames multi-frame
FCCH+SCH+BCCH+CCCH (main BCCH)
FCCH+SCH+BCCH+CCCH+SDCCH/4+SACCH/4 (combined BCCH)
BCCH+CCCH (extended BCCH)
SDCCH/8+SACCH/8 (main SDCCH)
Physical Combination of Logical Channel
TS 2, 4, 6

28. Copyright © 2010 Huawei Technologies Co., Ltd. All rights reserved. Page29
Structure of Main BCCH
1 multi-frame (51TDMA Frames) 235.38ms Downlink
Group Group1 Group2
Group3,4
(same
as
Group2)
Grpup5
Channel FSBX4 CX4 F SCX4 CX4 …… FS CX4 CX4 I
Frame
Number
01 2-5 6-910
1
1
12-
15
16-
19
20-39
4
0
4
1
42-45
46-
49
50
1 multi-frame (51TDMA Frames) 235.38ms Uplink
ChannelRRRRRRRRRRRRR
R……
R
RRRR
Frame
Number
0123456789101112 13-46 47
4
8
4
9
5
0
F:FCCH; S:SCH; B:BCCH; C:CCCH; R:RACH; I:IDLE

29. Copyright © 2010 Huawei Technologies Co., Ltd. All rights reserved. Page30
Structure of Combined BCCH
1 multi-frame (51TDMA Frames) 235.38ms Downlink
Group Group1 Group2 Group3 Group4 Grpup5
Channel F S
B×
4
C×
4
F S
C×
4
C×
4
F S
D0
×4
D
1×
4
F S
D2
×4
D
3×
4
F S
A0
×4
A1
×4
I
Channel F S
B×
4
C×
4
F S
C×
4
C×
4
F S
D0
×4
D
1×
4
F S
D2
×4
D
3×
4
F S
A2
×4
A3
×4
I
Frame
Number
0 1
2-
5
6-
9
1011
12
-
15
16
-
19
2021
22
-
25
26
-
29
3031
32
-
35
36
-
39
4041
42
-
45
46
-
49
50
1 multi-frame (51TDMA Frames) 235.38ms Uplink
Channel D3×4 R R A2×4 A3×4 R……R D0×4 D1×4 R R D2×4
Channel D0×4 R R A0×4 A1×4 R……R D0×4 D1×4 R R D2×4
Frame
Number
0-3 4 5 6-9 10-13 14-36 37-40 41-44 45 46 47-50
F:FCCH; S:SCH; B:BCCH; C:CCCH; D:SDCCH ;A:SACCH; R:RACH; I:IDLE

30. Copyright © 2010 Huawei Technologies Co., Ltd. All rights reserved. Page31
Structure of Logical Channel Combination
Frame-Main SDCCH
1 multi-frame (51TDMA Frames) 235.38ms Downlink
Channel
D0×
4
D1×
4
D2×
4
D3×
4
D4×
4
D5×
4
D6×
4
D7×
4
A0×
4
A1×
4
A2×
4
A3×
4
III
Channel
D0×
4
D1×
4
D2×
4
D3×
4
D4×
4
D5×
4
D6×
4
D7×
4
A4×
4
A5×
4
A6×
4
A7×
4
III
Frame
Number
0-34-7
8-
11
12-
15
16-
19
20-
23
24-
27
28-
31
32-
35
36-
39
40-
43
44-
47
4
8
4
9
5
0
1 multi-frame (51TDMA Frames) 235.38ms Uplink
Channel
A5
×4
A6×
4
A7×
4
I I I
D0
×4
D1
×4
D2×
4
D3
×4
D4×
4
D5
×4
D6×
4
D7
×4
A0×
4
Channel
A1
×4
A2×
4
A3×
4
I I I
D0
×4
D1
×4
D2×
4
D3
×4
D4×
4
D5
×4
D6×
4
D7
×4
A4×
4
Frame
Number
0-34-7
8-
11
12 13 14
15-
18
19
-
22
23-
26
27-
30
31-
34
35-
38
39-
42
43-
46
47-
50
D:SDCCH; A:SACCH; I:IDLE

31. Copyright © 2010 Huawei Technologies Co., Ltd. All rights reserved. Page32
Structure of Logical Channel Combination
Frame-TCH
T:TCH;A:SACCH; I:IDLE
1 multi-frame (26TDMA Frames) 120ms
Channel TT T T T TT…T A T,,,T T T T T T T I
Frame
Number
01 2 3 4 5
6…
11
12
13…
18
19 20 2122 23 2425
1 multi-frame (26TDMA Frames) 120ms
Channel T t T tT tT…t A T,,,tT t T t T t a
Frame
Number
01 2 3 4 5
6…
11
12
13…
18
19 20 2122 23 2425
Case of one full rate TCH
Case of two half rate TCHs
DTX
Frame 52
nd
to 59
th

32. Copyright © 2010 Huawei Technologies Co., Ltd. All rights reserved. Page33
0 1 2 3 2044204520462047
0 1 2 3 48 49 5047
0 1 24 25
0 1 24 25 1 49 500
0 1 4 5 762 3
TB
3
TB
3
GP
8.25
TB: Tail bitTB
3
TB
3
GP
8.25
GP: Guard period
TB
3
TB
3
GP
8.25
TB
3
TB
3
GP 68.25
58 information bits
26 training
sequences
58 information bits
Constant bit 142
Information bit 39Extended training sequence 64Information bit 39
Synchronous sequence 41Information bit 36
Normal burst (NB)
Frequency correction burst (FB)
Synchronous burst (SB)
Access burst (AB)
1 hyper frame=2048 super-frames=2715648TDMA frames (3 hours, 28 minutes, 53 seconds and 760 milliseconds)
1 super-frame=1326TDMA frames (6.12 seconds)
1 multiframe=26TDMA frames (120ms) 1 multiframe=51TDMA frames (3060/13ms)
1TDMA frame=8 timeslots (120/26=4.615ms)
1 timeslot=156.25 bit duration (15/26=0.577ms)
(1 bit duration: 48/13=3.68us)
BCCH
CCCH
SDCCH
TCH
SACCH/T
FACCH
Frame

33. Copyright © 2010 Huawei Technologies Co., Ltd. All rights reserved. Page34
PCH RACHAGCH
Downlink CCCH Uplink CCCH
How to determine the total CCCH resources of the cell? How to
allocate AGCH and PCH reasonably?
Configuration of Common Control Channel

34. Copyright © 2010 Huawei Technologies Co., Ltd. All rights reserved. Page35
Summary
In this course, we have learned:

Processing of Voice Signal

Radio Channel in Um Interface

Key Technical in Um Interface

35. Thank you
www.huawei.com