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Mobile Communications
1. Basic concepts
2. GSM/GPRS radio access
3. GSM/GPRS architecture and protocols
4. Universal Mobile Telecommunications System radio access
5. UMTS radio resource management
6. UMTS architecture and protocols
7. High Speed Down Link Packet Access
8 LTE
9. LTE ADVANCED
10. Mobile Network Engineering
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Mobile Communications
2.1 Physical layer2.2 Radio resource management
2. GSM/GPRS radio access
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2. GSM/GPRS radio access
2.1 Physical layer
frequencies and accessTDMA and GSM;
physical and logical channels in GSM and GPRS
coding
modulation techniques
GPRS physical layer
extensions:frames, super-frames, hyper-framese2.1
modulation techniquee2.2
e2.3 acquisition
GPRS timing advance
and power controle2.4
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FREQUENCY
SYSTEMBANDWIDTH
TIME
SCPC / FDMAsingle channel per carrier/frequency division multiple access
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FREQUENCY
FRAME INTERVAL
TIME
TDMATime Division Multiple Access
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FREQUENCYCODE
TIME
DS-CDMA
Direct Sequence - Code Division Multiple Access
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Space Division Multiple Access
.other words for frequency re-use
Theoretical Cluster
1
23
4
5
6
7 1
2
3
4
56
7
1
2
3
4
56
7
1 2 3 4 5 6 7
bandwidth
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Duplex operation
Rx RxTx Tx
frame
Time Division
Duplex mode
Frequency Division
Duplex mode
t
f-up f-down
f
system bandwidth
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GSM: the available bandwidth
Uplink
(MHz)
Downlink
(MHz)
Duplex
spacing
(MHz)
Bandwidth
(MHz)
P-GSM 900
E-GSM 900
R-GSM 900
GSM 450
GSM 480
GSM 750
890 915
880 915
876 915
1710 17851850 1910
450,4 457,6
478,8 486
747 762
824 849
935 960
925 960
921 960
1805 18801930 1990
460,4 467,6
488,8 496
777 792
869 894
DL=UL+45
DL=UL+45
DL=UL+45
DL=UL+95DL=UL+80
DL=UL+10
DL=UL+10
DL=UL+30
DL=UL+45
25
35
39
7560
7,2
7,2
15
25
GSM 900
DCS 1800PCS 1900
GSM 400
GSM 700
GSM 850
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GSM frequencies @ 900 MHz in Italy
TIM
WIND
OPIGSM TIMTACS GSM OPI
880,0 892,0 892,3 900,5 905,5 913,741 channels 41 channels
15 chann 9 channels16 cities
chan. 12-67 chan. 69-118
925,0 937,0 937,3 945,5 950,5 958,7
Other Italy (chan. 54-76)outside the 16 towns
TIM
WIND
OPI
GSM TIMTACS GSM OPI
41 channels 41 channels880,0 891,8 892,1 900,3 905,5 913,7
925,0 936,8 937,1 945,3 950,5 958,7
Other Italy (chan. 53-76)
outside the 16 towns
15 channels 10 channels16 citt
chan. 11-66 chan. 68-118
01.11.1998
01.03.1999
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TIM
WIND
OPIGSM TIMTACS GSM OPI
43 channels * 42 channels880,0 891,2 891,5 900,1 905,3 913,7
925,0 936,2 936,5 945,1 950,3 958,7
Other Italy 24 channelsoutside the 16 towns
57 channels 53 channels16 towns
CTI
915
960
15.09.1999
900 MHz frequencies - evolution
TIM
WIND
OPIGSM TIMTACS GSM OPI
42 channels 42 channels880,0 891,4 891,7 900,1 905,3 913,7
925,0 936,4 936,7 945,1 950,3 958,7
Other Italy 24 channelsoutside the 16 towns
57 channels 52 channels16 towns
CTI
915
960
01.07.1999
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Frequencies @ 1800 MHz
TIMTIM
1755
1850
WINDWIND
1865
1770
24 channels
1855
1760
24 channels50 channels
4th Operator4th Operator OPIOPI
1780
1875
1780
1880
50 channels
from 01.01.99 in 8 towns:RM, MI, NA, TO, BO, PA, FI, GE
from 01.07.99 over the whole national territory
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MSCMSC
BSCBSC
BSCBSC
BSCBSC
900 MHz900 MHz
BTSBTS
900 MHz900 MHz
BTSBTS
1800 MHz1800 MHz
BTSBTS
1800 MHz1800 MHz
BTSBTS
GSM 1800: the compatibility value
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BURSTTRANSMITTED
BY
TDMA FRAME(4.6 ms)
MOBILE 1
MOBILE 2
MOBILE 8TIME
TIME-SLOT: 577 s SIGNAL BURST: 543 s
GSM functions - TDMA access technique
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Time and power control
MS
p
t
BTS
tr, pr
tr: time of arrival of the MS burst
pr: received power
d
t
TS TS
Timing advance
TS TS
power control
. . . . . .
2dB granularity
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Time and power control (II)
-70
+4
-6
-30
power (dB)
10 8 10 10 8 10
s s
542.8 s
28 s to rump-up and 28 s to
switch-off max dynamic range of 70 dB 542 s to transmit
information
148 bit
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Burst structure
normal burst
T3
S1
S1
13
GP8.25
Coded Data57
Training Seq.26
Coded Data57
TypeNumber of Bits
148 Bit = 546.12 s
Stealing flagGuard Time
Tail bits
(guard bits)
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Burst structure (II)
random access burst
T
8T
3
Synchr. Seq.
41
Coded Data
36
GP
68.25
Type
Number of Bits
88 Bit = 324.72 s
TrainingGuard Period
Tails
Guard Period limiting
the max cell radius
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Burst structure (III)
frequency correction and synchronisation burst
T
3
T
3
Fixed bit sequence
142
GP
8.25
Type
Number of Bits
148 Bit = 546.12 s
Guard Period as for
the Normal BurstTails
Guard Period limiting
the max cell radius
Found syncr.
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GSM traffic channels
TCH/FS: Traffic Channel Full rate Speech
Speech transmission at a net bit rate of 13 Kbit/s (up anddown link)
TCH/HS: Traffic Channel Half rate Speech Speech transmission at half bit rate (up and down link)
TCH/F: Traffic Channel for Data transmission Data transmission at 9.6/4.8/2.4 Kbit/s (with different coding
schemes)
TCH/H: Traffic Channel for Data transmission Data transmission at halved speed (with different coding
schemes)
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BCCH: Broadcast Control Channel
point-to-multipoint unidirectional control channelbroadcasting system information to MS
CCCH: Common Control Channelup-link: RACH (Random Access CHannel)
down-link: PCH (Paging Channel)AGCH (Access Grant CHannel)
DCCH: Dedicated Control CHannel point-to-point bidirectional control channel
SACCH (Slow Associated Control CHannel)
FACCH (Fast Associated Control CHannel)
SDCCH (Stand Alone Dedicated Control CHannel)
GSM signalling channels
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..some other broadcast channels
FCCH: the Frequency Correction Channel Gives the mobile station the reference frequency of the
system
SCH: the Synchronisation Channel Gives the mobile station the training sequence for
demodulate the down-link information
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R
51 frames - 235.38 ms
D0 D1 D2 I I ID4 D5 D6 D7 A0 A1 A2 A3D3
D0 D1 D2 I I ID4 D5 D6 D7 A4 A5 A6 A7D3
F S B C F S F S F S F S IC C C C C C C C
D0 D1 D2I I I D4 D5 D6 D7 A0
A1 A2 A3
D3
D0 D1 D2I I I D4 D5 D6 D7 A4
A5 A6 A7
D3
BCCH + CCCH
(downlink)
BCCH + CCCH
(uplink)
8 SDCCH/8(downlink)
8 SDCCH/8
(uplink)
R R R R R R R R R R R R R R R R R R R R R R RR R R R R R R R R R R R R R R R R R R R R R R R R R R
F: TDMA frame for frequency correction burst
B: TDMA frame for BCCH
D: TDMA frame for SDCCH
R: TDMA frame for RACH
S: TDMA frame for synchronization burst
C: TDMA frame for CCCH
A: TDMA frame for SACCH/C
GSM - logical and physical channels
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51 frames - 235.38 ms
D3 RR A2 A3 D1 RR D2D0RRRRRRRRRRRRRRRRRRRRRRR
D3 RR A0 A1 D1 RR D2D0RRRRRRRRRRRRRRRRRRRRRRR
F S B C F S F S F S F S IC C D1 D2 D3 A0 A1
F S B C F S F S F S IC C
D0
D1 D2 D3 A2 A3D0 F S
BCCH + CCCH
+ 4 SDCCH/4(downlink)
BCCH + CCCH+ 4 SDCCH/4
(uplink)
F: TDMA frame for frequency correction burst
B: TDMA frame for BCCH
D: TDMA frame for SDCCH
R: TDMA frame for RACH
S: TDMA frame for synchronization burst
C: TDMA frame for CCCH
A: TDMA frame for SACCH/C
GSM - logical and physical channels
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T T IT T T T T T T T T T T T A T T T T T T T T T T
0 1 2 3 4 5 6 7 0 1 2 3 4 5 6 7 0 1 2 3 4 5 6 7
120 ms
TDMA Frame
T: Traffic Channel (TCH)A: Slow Associated Control Channel (SACCH)
2 1 21 2 1 2 1 2 1 2 1 2 1 2 1 2 1 2 1 2 1 2 1 2 1
120 ms
T T AT T T T T T T T T T T T A T T T T T T T T T T
Full Rate Channel
Half Rate Channels
GSM - associated channels
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GSM radio transmission and reception chain
a conceptual scheme
Channelencoder
orderingpartitioning
interleaving
ciphering burstformat
TxGSMmodulator
filters,
coherent
demodulat.
synchronisation
Viterbi equaliserBB demodulation
deciphering
burst
de-muxde-format
de-interleavingchannel decoder
Propagation channel
Source data
Output bits
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Speech coding
band-pass
AD
D
Alow pass
speech
decoder
speechencoder
channelcoder
channel
decoder
300 Hz
3.4 KHz
4 KHz
microphone
loud
speaker
t
analogue sampled
coded
1111111011011100
213
coding levels
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Channel codingand other protection mechanisms
Block codes
Convolutional codes
Distinction between: Speech data
Data services
Signalling data
Interleaving
Retransmission
Detection
Correction
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Channel coding
speech data
skbitsKbit /833.27012/138114/25.156/8.22 =
# of bits transmitted
per normal burst
information bits
per normal burst
multiframe inefficiency
for associated channel
voice
coding
13 Kbit/s
4 tail bitsReordering
(185)
convolutional
encoding
(1/2; L=5)
block code
(53, 50)
Channel encoding
260 bit
20 ms
50(1a)
132
(1b)
189
78 (2)
456 bit (20 ms)
22.8 kbit/s
Global bit rate
needed
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Reordering and Interleaving
speech data
10 1065432 987 13 141211 15
odd
even
burst
Voice sub-frames (reordering)
1 0 + i 8
2 1 + i 83 2 + i 8
4 3 + i 8
5 4 + i 8
6 5 + i 8
7 6 + i 88 7 + i 8
i = 0, 1, 2, .
114 bits transmitted
in each burst
Interleaving depth
= 8 bursts
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Channel coding and interleaving
data streams
data stream 9.6 kbit/s
terminal
codingdata stream 12 kbit/s
240 bit (12 kbit/s)
488 bit
456 bit
4
Convolutional encoding
R=1/2; L=5
Puncturing of 32 bit
6 12 18 24 24 24
6 12 18 24 24
10 1065432 987 13 141211 15
24 24 18 12 6
16 19 201817 21
22 blocks fromthe 456 data frame:
16 x 24 bit
2 x 18 bit
2 x 12 bit
2 x 6 bit
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Channel coding
signaling streams
10 1065432 987 13 141211 15
456 bit
Convolutional encoding
R=1/2; L=5
signaling info 184 bit parity 40 4
signaling info 184 bit
Block code (224, 1840)
odd
even
Spreading of the signalingblock over 4 consecutive
bursts
burst
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Base band frequency hopping
fi
fj
fk
TDMA frame
original allocation of the connection in progress
new frequency allocation through a frequency hopping mechanism
carriers
assigned to the
cell
network assigned jumping scheme
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Base band frequency hopping (I)
fk(t)
fk(r)
fi(r)
fj(r)
fl(r)
fi(t)
fj(t)
fl(t)
TDMA frame
TDMA frame
MS receiving
MS transmitting
measuring windows
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Modulation techniques
I
Q
Binary Phase Shift Keying
Quadrature Phase Shift KeyingI
Q
10
00
01
10
11
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GPRS - the physical layer
sharing resources and functions with GSM
Radio resource sharing withGSM voice and data services
Dynamic & static allocation of
the physical channels One or more slots to a singleGPRS user
One or more GPRS users on asingle slot
Radio-frequency partunchanged
Voice serviceGPRS service
dynamic border
variation
priority to voice
services
TDMA frame
slot sharingdata 2data 1
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GPRS data flow
BH Info Field BH Info Field BHBH Info FieldPrimary Block Following Blocks ...
FH Information Field FCSFrame
(LL-PDU)
Blocks
SNDCP layer
LLC layer
Physical layer
PH User DataPacket (N-PDU) Network layer
Compression/Decompression
Segmentation/Re-assembly (not shown)
Channel coding
Reordering & Partitioning
Interleaving
Burst formatting
RLC/MAC layer
Normal Burst Normal Burst Normal BurstNormal Burst
SH Information FieldSN-PDU
FH = Frame Header
FCS = Frame Check Sequence
BH = Block HeaderPH = Packet Header SH = SN-PDU Header
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Radio block coding
USF pre-coding
4 tail bits
rate 1/2 convolutional coding
puncturing
456 bits
USF BCSPayload
stealing flags
normal burst
CS1
CS2
CS3
CS4
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Coding parameters
SchemeCode
rate
Payload
(bits)
BCS
(bits)
Coded
bits
Tail
bits
Punctured
bits
Data rate
(kbps)
CS-1 1/2 181 40 4564 0 9.05
CS-2 ~ 2/3 268 16 5884 132 13.4
CS-3 ~ 3/4 312 16 6764 220 15.6
CS-4 1 428 16 456- - 21.4
Pre-coded
USF (bits)
3
6
6
12
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Scheme Maximum net payload(bytes)
Maximum netRLC/MAC data
rate (kbit/s)
Nominal data rate(kbit/s)
Application datarate (kbit/s)
CS-1 20 8 9.05 7.7
CS-2 30 12 13.4 11.5
CS-3 36 14.4 15.6 13.8
CS-4 50 20 21.4 19.2
Data rates
Application data rate (kbit/s) @ IP packet size (bytes)
Coding scheme 576 1200 1500
CS-1 7.3 7.7 7.7
CS-2 11 11.5 11.6
CS-3 13.2 13.8 13.9
CS-4 18.3 19.2 19.4
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00 11 77
RxTra
Rx
00 11 77
Tx
00 11
TtTt TxTx
00 77 00 11
TtaRx
Rx
00 77 00 11
Tra
11
Tx
Symmetric servicehalf-duplex terminal
Asymmetric service
half-duplex terminal
Tta : time to Tx
Tra: time to Rx
Time Slot Utilisation - simplex Terminal
Ttb : time to Tx,
no measures
Trb: time to Rx,
no measures
GPRS ph sical la er performance (II)
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GPRS: physical layer performance (II)
GSM @ 900 MHz (05.05) PDCH BLER 10%USF BLER 1%
PRACH BLER 15%
propagation
sensitivity
levels
C/I levels
PDTCH/CS1 (dBm) -104 -104 -104 -104 -103
PDTCH/CS4 (dBm) -101 -90 -90 --- ---
USF/CS1 (dBm) -104 -101 -103 -103 -101
PRACH/11 bit (dBm) -104 -104 -104 -103 -103
PDTCH/CS1 (dB) 13 9 10 9 9
PDTCH/CS4 (dB) 21 23 24 24 ---
USF/CS1 (dB) 19 10 12 10 10
PRACH/11 bit (dB) 8 8 8 8 10
Propagat. Charact.: static TU50 TU50 RA250 HT100
noFH ideal no FH no FH
FH
Propagat. Charact.: TU3 TU3 TU50 TU50 RA250
no FH ideal no FH ideal no FH
FH FH
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Reordering and interleaving
10 1065432 987 13 141211 15
odd
even
burst
456 bit (8x57bit)
4 bursts for transmission
rectangular interleaving
Interleaving depth 8:
minimising the BER (afterdecoding)
increasing the probability of blockre-transmission or erasure
Interleaving depth 4:
increasing the BERdecreasing the
probability of block re-
transmission or erasure
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BCCH
(CCCH)
radio packetsystem
broadcasting
GPRS channels - general
BTS
PBCCH(PCCCH)
GPRS dedicated broadcast
and Common Control
channels
Broadcast and Common
Control Channels shared with
GSM
GPRS specific system data
+
GSM system data
Only PCCCH has to be tracked by MS
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Packet Data Logical Channels (I)
Packet Common Control Channel (PCCCH): PRACH: random access (uplink)
PPCH: paging (downlink)
PAGCH: access grant (downlink)
PNCH: PTM-M notification (downlink)
Packet Broadcast Control Channel (PBCCH) (downlink)
Packet Traffic Channels: PDTCH: data traffic (up and down link)
Packet Dedicated Control Channels: PACCH: associated control (up and down link)
PTCCH/U: timing advance estimation (uplink))
PTCCH/D: timing advance information (downlink)
P k D L i l Ch l (II)
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Packet Data Logical Channels (II)
The radio blocks are transmitted over 4 bursts belonging to 4 consecutive
TDMA frames
Transmission on a Packet Data CHannel (PDCH):
transmission on PRACH and PTCCH/U is performed by sending anaccess burst
transmission on all the other packet data logical channels isperformed by sending radio blocks constituted by four consecutivenormal bursts
a Packet Control Acknowledgement can be sent via 4 accessbursts, if required by the network
P k t D t L i l Ch l (III)
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Packet Data Logical Channels (III)
PBCCH is mapped on one physical channel
PCCCH is mapped on one or several physical channels, following a 52-multiframe
PRACH is determined by Uplink State Flag (USF) set FREE and broadcaston the downlink or by a fixed allocation
A given PDTCH is mapped on one physical channel An MS can use up to 8 PDTCHs on the same carrier
A given PACCH is mapped on one physical channel and is allocateddynamically on a block basis
PTCCH/U is mapped on one of the PDCHs where PDTCHs are allocated to theMS; PTCCH/D is associated to several PTCCH/Us sharing the same PDCH
M ltif St t
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Multiframe Structure
52 TDMA frames divided in:
12 radio blocks B0-B11 (of 4consecutive frames)
2 frames used for PTCCH (T)
2 idle frames (X)
TDMA Frame 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51
Block B0 B1 B2 T B3 B4 B5 X B6 B7 B8 T B9 B10 B11 X
Idle frames
Radio Blocks
Frames for PTCCH
BCCH
MS
PDCH on which
PBCCH and
PCCCH are
mapped
A i l ltif d t
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A single multiframe - advantages
GSM multi-frames:
26 TDMA frames for voice/data
51 TDMA frames for BCCH, CCCH, SDCCH
26 frame voice, data
51 frame signaling
52 frame for signaling and traffic
GPRS multi-frame:
52 TDMA frames for data and signaling
statistical behaviour of data services
need for higher degree of flexibility
Key elements
for a choice:
Mobile Communications
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Mobile Communications
2.1 Physical layer
2.2 Radio resource management
2. GSM/GPRS radio access
2 GSM/GPRS radio access
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2. GSM/GPRS radio access
2.2 Radio resource management
GPRS radio resource management
static and dynamic channel allocation
GPRS Downlink Radio Blocks
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Data Block
Control Block
RLC/MAC Control Block
Radio block
MAC HdrControl Header
(optional)RLC/MAC Signaling
MAC Header
RLC Data Block
Radio block
RLC Header RLC Data
USF S/P RRBP
Payload
Type
MAC Hdr
Spare bits
(if any)
GPRS Downlink Radio Blocks
GPRS Downlink Radio Blocks
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GPRS Downlink Radio Blocks
The radio blocks adopt different configurations in function of the transmission direction (upordown link). Moreover, their configuration depends on the role they are assigned to: data orcontrol transport.
The radio block is subject to retransmission for error protection. The retransmission doesnot take place for a single radio block but for a group of radio blocks: those contained in theretransmission window, concerning 64 radio blocks (both in the up and in the down link).The retransmission involves then more than one GPRS users: those who can share the same
time slot. The MAC layer contains the headerof the upper layer frames (RLC). As for the MACheader, it contains some data range driving the retransmission mode.
The Up Link State Flag (USF) transmitted on the down link, is composed of 3 bits. It specifiesthe MS which is allowed to transmit on the up link along the 4 subsequent time slots (1block) and, set to 0, the presence of a Packet Random Access Channel (PRACH) always onthe up link. Hence, the maximum user multiplexing level on the up link over the same timeslot is 7. Often on the up link, some signalling messages associated to the traffic received on
the down link are to be transmitted: another USF value has then to be reserved. This reducesto 6 the maximum multiplexing degree on the up link.
The supplementary/polling (S/P) range contains1 bit; it states the presence (or the absence)of the subsequent range.
The Relative Reserved Block Period (RRBP) is composed of 2 bits specifying the radio blockperiod when the MS must transmit a control packet which may be for instance a PacketControl Acknowledgement (PACK) transmitted over a Packet Associated Control Channel
(PACCH). The MS that has to transmit is the one identified by the Temporary Flow Identity(TFI) specified in the RLC header.
The Payload Type (2 bits) specifies the kind of information transported by the radio block(Data or Control) and, whenever the block is a control block, it specifies if the subsequentrange (RLC header) present or not present.
GPRS Uplink Radio Blocks
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Data Block
RLC Data Block
Radio block
RLC Header RLC Data
Control Block
RLC/MAC Control Block
Radio block
MAC Hdr
MAC Hdr RLC/MAC Signaling
MAC Header
RCountdown
value
Payload
TypeSI
MAC Header
R sparePayload
Type
Spare bits
(if any)
GPRS Uplink Radio Blocks
GPRS Uplink Radio Blocks
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On the up link the following ranges are present: The Retry (R) (1 bit) designates if the MS has sent the Packet Channel
Request at least one time within the Temporary Block Flow (TBF). The TBFdefines a physical connection utilised for one or more LL-PDU over one or
more PDCH in a point-to-point mode between the MS and the Network. The Stall Indicator(SI) is composed by 1 bit. It establishes if the counter of
the transmission window at the RLC level can be either increased or not.
The Countdown Value bears 4 bits specifying how many RLC data blocksare still to be transmitted within the current Temporary Block Flow. The
Spare range (5 bit) are not utilised by teh network.
The Payload Type (2 bits) specifies as for the down link, the kind ofinformation carried by the radio block (Data or Control) and, whenever theblock is a control block, it specifies if the subsequent range (RLC header)is either present or not.
p
RLC header and data - data block
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Data Block
up and down link)
Control Block
(down link)
RLC/MAC Control Block
Radio block
MAC HdrControl Header
(optional)RLC/MAC Signaling
RLC Header
RLC Data Block
Radio block
RLC Header RLC Data
2 byte
MAC Hdr
Spare bits
(if any)
RLC header and data data block
2 byte
RLC Header
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Uplink Transmission and contention resolution
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p
MS NetworkPacket Channel Request
Packet Uplink Assignment
Packet Resource Request
Packet Uplink Assignment
PRACH or RACH
PAGCH or AGCH
PACCH
PACCH
(Optional)
(Optional)
Access
PRACH
random choiceMS
retransmission
MS network
Packet Channel Req.
Packet uplink assig.
PRACH
PAGCH
physical channels
assigned (PDCH)
USF for each
PDCH assigned
TFI (TBF)
established
1 physical channel
assigned (PDCH)
Packet resource req.
MS>netw. over PDCH
Packet uplink assign.
(USF, TFI)
1-phase 2-phases
Contention resolution and resource allocation
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Data Block
Packet Uplink Ack/Nack
Data Block (last)
Access and Assignment
MS Network
PDTCH
PACCH
PDTCH
Packet Uplink Assignment
Packet Control AcknowledgementPACCH
PACCH
Data BlockPDTCH
Data BlockPDTCH
Data Block (last in send window)
PDTCH
Data BlockPDTCH
Data BlockPDTCH
Data BlockPDTCH
Data BlockPDTCH
Packet Uplink Ack/Nack (final) PACCH
Uplink data transfer
Resource allocation
Possible limitations (network side) on
the number of transmitted blocks
Selective retransmission required
through Packet uplink Ack/Nack
Resource re-assignment along the
packet transfer:
packet uplink assign. (over PACCH andbearing the RRBP for answer)
packet control acknowledgment viaPACCH reserved through RRBP
Resource release started by MS throughcount/down procedure.
Packet uplink final ACK (netw.) and
Packet control ack (MS) are sent
Uplink transfer channel allocation
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p
Dynamic Allocation:
the MS transmits its radio blocks on the assigned time
slots with the assigned USF
Fixed Allocation:
fixed uplink resource allocation to the MS based on a
bitmap indicating the assigned blocks per time slot No need to monitor the downlink for the USF
Extended Dynamic Allocation:
monitoring of the USF without transmitting and receivingsimultaneously
Recommended