Um Interface and Radio Channels

Contents

Overview
Processing of Voice Signal
Radio Channel

Radio Interface

Another MSC

HLR/AUC

SMC

PSTN ISDN

OMC

MS

Um

MS

A-bis

BSC

A

BTS

MSC/VLR

Communication management (CM)

Radio resources management (RR)

Mobility and security management (MM)

Integrated management

TCH0

Radio Access Technology

FDMA

TDMA

CDMA

User

User

User

User

User

User

User

User

Radio Access Technology

FDMA

TDMA

CDMA

User

User

User

User

User

User

User

User

Contents

Overview
Processing of Voice Signal
Radio Channel

Voice Signal Processing

(A/D)

20 ms

22.8kbit/s

13kbit/s

8KHz,13bit

33.8kbit/s

Channel coding

Interleaving

Encryption)

Burst formatting

Modulation

Transmission

Voice

Analog-Digital Conversion

Speech Coding

The Enhance Full Rate coding mode is called CELP (Code

Channel Coding

13kbit/s

260 bits(FR)

112 bits(HR)

244 bits(EFR)

12.2kbit/s

5.6kbit/s

(A/D)

20 ms

8KHz,13bit

Voice

Channel coding

22.8kbit/s

456bits(FR/EFR)

228bits(HR)

11.4kbit/s

Block Coder

1:2
Convolutional
Coder

1 2 3 4 5 6 7 8 ... ... 452

1 2 3 4 5 6 7 8 ... ... 452

Voice Burst

Tail bit

Tail bit

Guard period

Data

Data

Training sequence

(A/D)

20 ms

22.8kbit/s

13kbit/s

8KHz,13bit

33.8kbit/s

Channel coding

Interleaving

Encryption)

Burst formatting

Modulation

Transmission

Voice

Voice Signal Processing

Transmission delay t

Transmission delay t

TA

The mobile phone should
send the

Timing Advance (TA)

Transmission delay t

Transmission delay t

TA

The mobile phone should
send

Frequency Hopping

Frequency

f 0

Frame

f 1

f 2

f 3

f 4

Time

Frequency Hopping

Frequency

f 0

Frame

f 1

f 2

f 3

f 4

Time

Prolong battery life and reduce interference

DTX

DTX: Discontinuous Transmission
Shut off the transmission

DTX

DTX: Discontinuous Transmission
Shut off the transmission at voice intervals;
Only transmit SID

Power Control

Prolong battery life
Reduce network interference
Include both uplink power control and

Contents

Overview
Processing of Voice Signal
Radio Channel

Frequency

200kHz

15/26ms

BP

Slit

Time

Frame and Channel

Physical Channel of Logical Channel

8bit

41 synchronous bits

36 encrypted bits

3bit

68.25bit

Tail bit

Tail bit

Guard interval

Data

Guard interval

3bit

142bit

3bit

8.25bit

Tail bit

Tail bit

Data

3bit

39

3bit

142 modulation bits

3bit

8.25bit

Tail bit

Tail bit

Guard interval

Burst

3bit

57 encrypted bits

57 encrypted bits

3bit

8.25bit

Tail bit

Tail

Broadcast control channel
(BCH)

Control channel

Common control channel
(CCCH)

Voice channel (TCH)

FCCH

SCH

BCCH

TCH/F

AGCH

RACH

SDCCH

FACCH

SACCH

TCH/H

PCH

Common channel
(CCH)

Dedicated

Downlink Logical Channel

Downlink Logical Channel

Uplink Logical Channel

Uplink Logical Channel

Use of Logical Channels

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

Structure of Main BCCH

F:FCCH; S:SCH; B:BCCH; C:CCCH; R:RACH; I:IDLE

Structure of Combined BCCH

F:FCCH; S:SCH; B:BCCH; C:CCCH; D:SDCCH ;A:SACCH; R:RACH; I:IDLE

Structure of Logical Channel Combination Frame-Main SDCCH

D:SDCCH; A:SACCH; I:IDLE

Structure of Logical Channel Combination Frame-TCH

T:TCH;A:SACCH; I:IDLE

Case of one full rate

0

1

2

3

2044

2045

2046

2047

0

1

2

3

48

49

50

47

0

1

24

25

0

1

24

25

1

49

50

0

0

1

4

5

7

6

2

3

TB

3

TB

3

GP

8.25

TB: Tail bit

TB

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

0

1

2

3

2044

2045

2046

2047

0

1

2

3

48

49

50

47

0

1

24

25

0

1

24

25

1

49

50

0

0

1

4

5

7

6

2

3

TB

3

TB

3

GP

8.25

TB: Tail bit

TB

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

PCH

RACH

AGCH

Downlink CCCH

Uplink CCCH

How to determine the total CCCH resources of the

Summary

In this course, we have learned:
Processing of Voice Signal
Radio Channel in