TDMA FRAME

MODULE 3

Chapter 03

Topics to be covered in this session :- TDMA Frame TDMA Multiframes Superframe Hyperframe

Session Objective

Hyperframe

TDMA Frame

0 1 2 3 4 5 6 7

Uplink frequency band : 890 915 MHz

12345... Uplink frequency band : 890 915 MHz

Downlink frequency band : 935 - 960 MHz

124 channels (of 200 kHz each) in each band.

Each channels has a TDMA structure with 8

timeslots.

.

.124

TDMA frame

0 1 2 3 4 5 6 7

577us577us

TDMA frame duration:- 4.615 ms

No of bits:- 156/time slot

Burst duration:- .546 ms

TDMA Multi Frame26-TDMA multi-frame

Succession of 26 TDMA frames, and corresponds to the 26 x 8 BP or 120 ms.

51-TDMA multi-frame Succession of 51 TDMA frames, and corresponds to the 51 x Succession of 51 TDMA frames, and corresponds to the 51 x

8 BP cycle.

Super frame Succession of 51 x 26 TDMA frames (6.12 sec).

Hyper frame Numbering period, 2048 x 51 x 26 x 8 Broadcast

Period long, or 3 hours, 28 minutes, 53 seconds and 760 milliseconds.

26 Frame Traffic Channel Multi frame

0 1 2 3 4 5 6 7 0 1 2 3 4 5 6 7 0 1 2

Idle

0 1 2 3 . 12 . 25

SACCH

MF0 - MF11 & MF13 MF24:- Traffic

120ms

51 Frame Control Channel Multi frame

0 1 2 3 4 5 6 7 0 1 2 3 4 5 6 7 0 1

idle

0 1 2 3 4 12 25 49 50

idle

235.36ms

BCCH / CCCH Multiframe

S B B B B C .. F S C ... F S ..F I

0 1 2 3 4 5 6 10 11 40 41 50

R R R R R R R R R R R R R R R R R

0 1 2 3 4 5 6 10 11 40 41 50

D/L

U/L

F - FCCH - 0 , 10 , 20 , 30 , 40 : 5 times

S - SCH - 1 , 11 , 21 , 31 , 41 : 5 times

I - IDLE - 50

B - BCCH - 2 , 3 , 4 , 5

C - CCCH - Either PCH or AGCH

R - RACH - All 51 in UP Link

R R R R R R R R R R R R R R R R R U/L

Superframe

Any given frame number will only occur simultaneously in both multiframes every 1326 TDMA frames (26 X 51).

This number of TDMA frames is termed as aSuperframe and it takes 6.12 Sec to transmit.

By this arrangement, the timing of the TCH multiframe is By this arrangement, the timing of the TCH multiframe is always moving in relation to that of the CCH multiframe and this enables a MS to receive and decode BCCH information fromsurrounding cells

HYPER FRAME

Hyperframe consists of 2048 Superframes Used in connection with Ciphering and Frequency

hopping Hyperframe duration is 3 Hrs - 28 Min 53 Sec 760

msms After this time the ciphering and frequency hopping

algorithms are restarted.

TDMA Burst

Guard Tail User S Training S User Tail

0 1 2 3 4 5 6 7

Guard

Space

Tail

3

User

Data

57

S

1

Training

26

S

1

User

Data

57

Tail

3

Guard

Space

REVIEWIn this session we discussed about the:- TDMA Frame TDMA Multiframes Superframe Hyperframe Hyperframe

Presented By:- Gaurav Kumar