BSS Hardware

© Alcatel University - 8AS 90200 1394 VH ZZA Ed.011

© Alcatel University - 8AS 90200 1394 VT ZZA Ed.01

GSM – EGPRS Synthesis

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E-GSM frequencies

Uplink E-GSM frequencies





Radio Interface3.4.1 Speech Processing: Radio Channel generation

Speech coding: Adaptive Multi-Rate (AMR)

t Voice quality benefits:n It provides the best voice quality according to radio conditions

n It increases in the same time the offered capacity due to the provision of half-rate channels

n 2 extensive sets of “codec modes”:– 6 possible rates in HR channels: 4.75, 5.15, 5.9, 6.7, 7.4, 7.95 Kbps– 8 possible rates in FR channels: 4.75, 5.15, 5.9, 6.7, 7.4, 7.95, 10.2,12.2 Kbps

Channel coding = speech protectionSpeech coding = speech information

Medium radioconditions

Bad radioconditions

Good radioconditions

t The benefit of AMR for the operator is to increase the quality of speech during the conversations and to increase in the same time the offered capacity due to the provision of half-rate channels.

t On the radio interface, the AMR can only be used with AMR mobiles. On the A interface, the AMR can only be used if the NSS implements it.

t When looking at current GSM codecs (Full Rate (FR), Half Rate (HR) and Enhanced Full Rate (EFR)), each of them answers to only one face of capacity and quality requirements:n EFR brings a higher speech quality than FR but with no noticeable impact on

capacity,n HR answers to capacity requirement, but suffers from a poor speech quality in

bad radio conditions or in tandeming (MS to MS calls).t AMR is a new technology defined by ETSI which relies on two extensive sets of

“codec modes”. One has been defined for FR and one for HR. When used in combined FR and HR mode, AMR brings a new answer to the trade-off between capacity and quality:n Speech quality is improved, both in full-rate and half-rate.n Offered capacity is increased due to the provision of half-rate channels

allowing to densify the network with low impact on speech quality.t The AMR technology provides also the advantage of providing a consistent set of

codecs once for all instead of introducing new codecs one by one in the time.t In the Alcatel product, AMR can be offered in 2 ways:

n In FR mode only, for operators who do not face capacity issues and want to benefit from the optimized quality of speech.

n In combined FR/HR mode, for operators who want to benefit from the above defined trade-off between quality of speech and capacity.





3 The Base Station Subsystem3.5 Radio Interface

t GPRS / EGPRS throughput

CS2CS1

Coding Scheme Modulation Maximum rateper PDCH (kb/s)

GMSKGMSK

13.49.05

CS4CS3

GMSKGMSK

21.415.6

GPR

S

MCS9MCS8

8-PSK8-PSK

59.254.4

MCS7MCS6MCS5

MCS4MCS3MCS2MCS1

8-PSK8-PSK8-PSK

44.829.6 / 27.2*

22.4

17.614.8 / 13.6*

11.28.8

GMSKGMSKGMSKGMSK

* in case of padding

EGPR

S

B8 Number of GCHrequired per PDCH

11

22

54432

2211

Idem B7Idem B7

B9 Nbr of GCHrequired per PDCH

1.000.73

1.641.25

4.494.143.492.861.86

1.501.331.000.89





3.3 Transceiver Equipment (TRE)

TRE G3 Types

t TRE G3 and G4 band and power comparison:

45.44 dBm35 W1900TRPM

48.03 dBm63.5 W1800TRDH

45.69 dBm37 W1800TRDM

45.44 dBm35 W900TRGM

Output level

(dBm)

Power

(Watt)

Band

(MHz)

Variant

30 W; 44.8 dBm35 W; 45.4 dBm1800TRADE

30 W; 44.8 dBm45 W; 46.5 dBm900TRAGE

25 W; 44.0 dBm60 W; 47.8 dBm1800TADH

12 W; 40.8 dBm35 W; 45.4 dBm1800TRAD

15 W; 41.8 dBm45 W; 46.5 dBm900TRAG

25 W; 44.0 dBm45 W; 46.5 dBm1900TRAP

25 W; 44.0 dBm60 W; 47.8 dBm900TAGH

15 W; 41.8 dBm45 W; 46.5 dBm850TRAL

Output Power, 8-PSK

Output Power, GMSK

Band

(MHz)

Variant

EDGE+

« TRA »





t TRE G4 GMSK/8PSK power difference






t The coding scheme depends on MS position in the cell





t MFS Evolution Capacity and performances

(*) 2 E1 are reserved for the GP synchronisation in case of centralized mode

Nota : from 9 GP in MFS Evolution, only 12 E1 is applicable on B8 MR6/7 and B9 MR1 ed6 , GP board (A9130 MFS Evolution) capacity is equal to the GPU board on MFS A9135 (legacy).

t Increase of capacity compared to the legacy is available with B9 MR4

A9130 MFS EvolutionEvolution & Introduction

reminder

Max number of PDCH per GP (A9130)B8 / B9 MR1 ED6

GP configuration max nbr PDCH (*) 12 E1(*)/board 16 E1(*)/boardGPRS CS2 240 960 960

CS3 220 864 892CS4 204 660 804

EGPRS MCS1 232 856 856MCS2 228 836 836MCS3 212 796 796MCS4 200 720 772MCS5 180 584 704MCS6 172 460 660MCS7 140 312 448MCS8 116 264 380MCS9 108 244 348

B9 MR4

Extensible Non Extensible






t Number of GCH per Coding scheme






t 1 GCH per PDCH as in B7

t (manual setting for B8 only - dynamic / automatic in B9)






t 5 GCH per PDCH: manual setting for B8 only !!

t (dynamic / automatic in B9)





S2 Activation of High Speed Data ServicesHardware configuration management

t Configuration of the secondary Abisn Objective : Attach a secondary Abis




Alcatel University - 8AS 90200 1394 VT ZZA Ed.01

2.1 Hardware configuration managementAbis Extra TS configuration

1

2

3

t When creating a BTS, the operator has to enter only the total number of Extra TS for the entire BTS (1).

t If necessary, he may modify the maximum allowed number of TS on primary Abis (2)(same meaning as in B8) and declare a Secondary Abis link (3).





ChannelEncoding

Radio Interface3.4.1 Speech Processing: Radio Channel generation

Speech Digitization

and Encoding

InterleavingBurst

Formatting Encryption Modulation Transmission

ReceptionDemodulationDecryptionBurst

DeformattingDe-

interleavingChannel

DecodingSpeech

Decoding

POWER CONTROL

260 bits / 20 ms:13 kbit/s 22.8 kbit/s(per channel)

270.8 kbit/sFR Speech frames: (modulated...……...





Radio Interface3.2.2 Physical Channels: TDMA Frame

1 BTS (eg. 3 carriers)

TDMA frame = 4.615 ms

1 "CHANNEL" (in 1 direction)

Same "CHANNEL" (if bidirectional)

time axis

Time slot (or burst window)

1 2 3 4 5 6 70 1 2 3 4 5 6 70 1 2 3 4 5 6 70

1 2 3 4 5 6 70 1 2 3 4 5 6 70 1 2 3 4 5 6 70

22

17

7

22

17

7

Time shift betweentransmit and receive: 3 TS

Frequencyaxis

UPLINKBand

MS -> BTS

DOWNLINKBand

(BTS ->MS)





1 What is GPRS ? 1.4 MS multislot class

NAxx119 to 29like 10

000NA88218011NA77217121NA66216131NA55215131NA44214131NA33213121544112121534111121524110121523191215141813143317131423161314221513141314132322131323121224221111

TrbTraTtbSumTxRxTypeMulti-slotclass

t MS typen Type 1 are simplex MS, i.e. without duplexer: they are not able to transmit and

receive at the same timen Type 2 are duplex MS, i.e. with duplexer: they are able to transmit and receive

at the same timet Rx

n Maximum number of received timeslots that the MS can use per TDMA frame. The receive TS shall be allocated within window of size Rx, but they need not be contiguous. For SIMPLEX MS, no transmit TS shall occur between receive TS within a TDMA frame. This does not take into account measurement window (Mx).

t Tx n Maximum number of transmitted timeslots that the MS can use per TDMA

frame. The transmit TS shall be allocated within window of size Tx, but they need not be contiguous. For SIMPLEX MS, no receive TS shall occur between transmit TS within a TDMA frame.

t SUM n Maximum number of transmit and receive timeslot (without Mx) per TDMA

frame

t Meaning of Ttb, Tra et Trb changes regarding MS types.n For SIMPLEX MS (type 1):

– Ttb Minimum time (in timeslot) necessary between Rx and Tx windows– Tra Minimum time between the last Tx window and the first Rx window of

next TDMA in order to be able to open a measurement window– Trb same as Tra without opening a measurement window





Radio Interface3.2.3 Physical Channels : the Normal Burst

TDMA frame = 4.615 ms

CHANNEL

time axis

guard time

Training sequence

577 µs

Time Slot (TS) or Burst Period (BP)

1 2 3 4 5 6 70 1 2 3 4 5 6 70 1 2 3 4 5 6 70

22

17

7

Burst

”Data” (114 symb)

t On the air interface, “bursts” are used to transmit information inside each time slot. The different types of burst are linked with the information to be transmitted. The most commonly used is the normal burst, the structure of which is described above. Other types of burst are used for frequency monitoring, synchronization and access (short burst).

t The size of the normal burst is slightly shorter than the size of the time slot (577µs):a “guard” time is used to take into account the possible variation of the time for the transmission of the signal between the MS and the Base Station when the MS moves.

t A Normal burst is composed of:n one training sequence, in the middle of the burst (26 symbols).n 2 blocks of data, 57 symbols each (on both sides of the training sequence): these coded and

ciphered data can be:– speech, or – (user) data, or– signaling information.

n 2 symbols on both side of the training sequence (1+1) used to transmit signaling information (GMSK only) instead of traffic during a call (stealing flags).

n Additional symbols at each end of the burst (3+3).t Due to the possible reflections on obstacles, the signal transmitted between MS and BTS is a multi-

path signal. Inside the receiver (BTS or MS), an equalizer is used to cope with the different paths in order to decode properly the final signal. The training sequence is a sequence of bits, known beforehand, which is used by the equalizer in order to improve the demodulation/decoding process on the other bits of the bursts:

(The receiver is “trained” on a pre-determined sequence (the training sequence) and afterwards it improves its performance on the rest of the burst …)





Radio Interface3.2.3 Physical Channels : the Normal Burst

t Training Sequences:8 different bit patterns, chosen so that:

n They are easily recognizable (very accurate auto-correlation function)

n They are easily distinguishable from one another (little correlation between each pattern)

t Stealing Flags:

26 symb

"Stealing Flags“ GMSK ONLY

S = 0

S = 1

57 symb 57 symb+

+

Traffic (or Signaling out of call)

Signaling during call

Training sequence

57 symb 57 symb

GMSK: 1 bit / symbol

8-PSK: 3 bits / symbol

Modulation gross bit rate

t The GSM burst is divided into 156.25 symbol periods. A GSM burst has a duration of 3/5200 seconds (577 µs), (3GPP TS 05.02).

t For GMSK modulation, a symbol is equivalent to a bit (3GPP TS 05.04)n GMSK burst is composed of 156.25 bits:

– 6 tail bits– 26 training sequence bits– 116 encrypted bits– 8.25 guard period (bits)

n Modulation gross bit rate = (156.25 bits) / (3/5200 seconds) = 270 kb/s

t For 8-PSK modulation, one symbol corresponds to three bits (3GPP TS 05.04)n 8-PSK burst is composed of 156.25 x 3 = 468.75 bits:

– 18 tail bits– 78 training sequence bits– 348 encrypted bits– 24.75 guard period (bits)

n Modulation gross bit rate = (468.75 bits) / (3/5200 seconds) = 810 kb/s





S1 : Introduction 1.3 Main features and characteristics

t In order to get higher throughputs, the 8-PSK (8 Phase Shift Keying) modulation is used.

t Only TRE G4 are compatible with both GMSK and 8-PSK modulations.

n 8-PSK modulation encodes 3 bits per

modulated symbol, as opposed to 1 bit per

symbol in GMSK.

n This roughly triples the bit rate compared

to GMSK.

(0,1,0)

(0,1,1)

(1,1,1)

(1,1,0)

(1,0,0)

(1,0,1)

(0,0,0)

(0,0,1)

t One of the modulation used by EGPRS is based on the 8-PSK (Phase Shift Keying). In this modulation, we define 8 states of different phases corresponding to all combinations of groups of 3 bits. Each time the phase will shift to the corresponding position on the circle (see above).

t While shifting from one phase value to another the signal modifies its amplitude.





Radio Interface3.3.1 Logical Channels: Principle of Mapping with the Physical

Channels

1 2 3 5 6 7TS

Frequency Correction

Timing synchronization

System information

Subscriber paging

Response to access request

Out of call signaling -> MSi

Power Control -> MSi

Traffic samples -> MSj

In call signaling -> MSj

BTS MS

example: "Beacon" frequency, downlink:

FCCH

SCH

BCCH

PCH

AGCH

SDCCH

SACCH

TCH

FACCH

0 4

FCCH

BCCH

PCH

AGCH

SDCCH

SACCH

TCH

FACCH

SCH1

2

3

4

Traffic sample decoding

In call signaling receipt

Power Control

Out of call signaling receipt

Mobile presynchronization

Subscriber paging

Response to access request

t The 4 families of Logical Channels previously described can be mapped with the Physical Channels in the following way (one possible mapping): n 1 = Common Broadcast Channels TS0, beacon frequency: alwaysn 2 = Common Access Channels TS0, beacon frequency: alwaysn 3 = Dedicated Signaling Channels TS1 in this example

(in another possible mapping, they could be combined with “1” & “2” on TS0)n 4 = Dedicated traffic Channels All other TS

(from TS2 to TS7 in this example) t The different channels of the same family are therefore multiplexed in the same

Time Slot but in consecutive frames:for example the beacon, the timing synchronization, the system information always use the Time Slot 0 but in Frame 1, Frame 2, Frame 3, etc.

t In a cell with more than 1 frequency:Dedicated Signaling Channels (“3” in the diagram) could be located on another frequency.





2 GPRS Operation2.2 MS Mobility Management States

Idle

Ready

Stand-by

GPRS Attach

GPRS Detach

READY timer expiry

PDU transmission

t MS MM states

t IDLE (GPRS) StateIn GPRS IDLE state, the subscriber is not attached to GPRS mobility management. The MS and SGSN contexts hold no valid location or routeing information for the subscriber. The subscriber-related mobility management procedures are not performed. Data transmission to and from the mobile subscriber and the paging of the subscriber is not possible. The GPRS MS is seen as not reachable in this case.In order to establish MM contexts in the MS and the SGSN, the MS shall perform the GPRS Attach procedure.

t STANDBY StateIn STANDBY state, the subscriber is attached to GPRS mobility management. Pages for data or signalling information transfers may be received. It is also possible to receive pages for the CS services via the SGSN. Data reception and transmission are not possible in this state.The MS performs GPRS Routeing Area (RA) and GPRS cell selection and re-selection locally. The MS executes mobility management procedures to inform the SGSN when it has entered a new RA. The MS does not inform the SGSN on a change of cell in the same RA. Therefore, the location information in the SGSN MM context contains only the GPRS RAI for MSs in STANDBY state.The MS may initiate activation or deactivation of PDP contexts while in STANDBY state. A PDP context shall be activated before data can be transmitted or received for this PDP context.

t READY StateIn READY state, the SGSN MM context corresponds to the STANDBY MM context extended by location information for the subscriber on the cell level. The MS





2 GPRS Operation2.3 MS Radio Resource Operating Modes

Packettransfer mode

Packetidle mode

Packetidle mode

Ready Standby

RR

MM

t MS RR operating modes vs MS MM states

t Packet idle modeIn packet idle mode no Temporary Block Flow. Upper layers can require the transfer of a LLC PDU which, implicitly, may trigger the establishment of TBF and transition to packet transfer mode.While operating in packet idle mode, a mobile station belonging to GPRS MS class A may simultaneously enter the different RR service modes. A mobile station belonging to either of GPRS MS class B or C leaves both packet idle mode and packet transfer modes before entering dedicated mode, group receive mode or group transmit mode.

t Packet transfer modeIn packet transfer mode, the mobile station is allocated radio resource providing a Temporary Block Flow on one or more physical channels. Continuous transfer of one or more LLC PDUs is possible. Concurrent TBFs may be established in opposite directions. Transfer of LLC PDUs in RLC acknowledged or RLC unacknowledged mode is provided.When selecting a new cell, mobile station leaves the packet transfer mode, enters the packet idle mode where it switches to the new cell, read the system information and may then resume to packet transfer mode in the new cell.While operating in packet transfer mode, a mobile station belonging to GPRS MS class A may simultaneously enter the different RR service modes. A mobile station belonging to either of GPRS MS class B or C leaves both packet idle mode and packet transfer modes before entering dedicated mode, group receive mode or group transmit mode.





2 MFS Telecom Functional Description2.1 PCU Functions

t PDCH allocation in a cell (2/2)AllocatedSPDCH

Max_PDCH - Nb_TS_MPDCH

Max_PDCH_High_Load - Nb_TS_MPDCH

Min_PDCH - Nb_TS_MPDCH

23

4 5

1

t (1)The cell is activated for PS traffic and MAX_SPDCH_DYN is equal to (MAX_PDCH -Nb_TS_MPDCH). Resources (Min_PDCH - Nb_TS_MPDCH) are requested to the BSC (pre-allocation phase).

t (2)Additional PDCHs are requested to the BSC until the maximum number of SPDCHs is allocated.

t (3)The BSC sends a Load Indication with a decreased MAX_SPDCH_DYN. A soft preemption is activated on the exceeding PDCHs. T_PDCH_Preemption is activated.

t (4)During the soft preemption process, T_PDCH_Preemption expires>. A fast preemption process is activated on the PDCHs that are still marked as soft preempted.

t (5) The BSC sends a load indication with an increased MAX_SPDCH_DYN.The PS traffic increases until MAX_SPDCH_DYN is reached.

t Max_PDCH_High_LoadDefines the lower value of the maximum number of PDCHs (SPDCHs + MPDCHs) per cell when the cell is in high load situation. This parameter indicates the lower limit of the load adaptation mechanism.

t Max_PDCHDefines the maximum number of PDCHs (SPDCHs + MPDCHs) that can be allocated in a cell. Whatever the PS traffic is, there will never be more than Max_PDCH PDCHs





- Out of call signaling, such as location update, authentication, transition to encrypted mode, assignment of a traffic channel, etc.

SACCHSlow Associated Control

SDCCHStandalone Dedicated Control

Radio Interface3.3.3 Logical Channels: Channel Mapping

Structure of the Multiframe in "Time Slot" 1

LOGICALCHANNEL

8 TSs every 2x51 frames, giving 456 bits / 235 ms

---> 1.94 kbit/s

OCCURRENCEand/or USABLE BIT RATE

4 TSs every 2x51 frames, giving 456 bits / 470 ms

---> 950 bit/s

- Non-urgent procedures (background), occurrence ~0.5 sec: measurement reports, power monitoring, timing advance, + Short Message Service during call (SMS)

ROLES and USES of INFORMATION CARRIED

DOWNLINK

(Multiframes : 51 frames)

D = SDCCH A = SACCH

UPLINK

-

-- -

- -D0 D1 D2 D3 D4 D5 D6 D7

D0 D1 D2 D3 D4 D5 D6 D7

A0

A4

A1 A2 A3

A5 A6 A7

D0 D1 D2 D3 D4 D5 D6 D7

D0 D1 D2 D3 D4 D5 D6 D7 A0

A4

A1 A2 A3

A5 A6 A7

-

-- -

- -





Gb interfacePermanent Virtual Circuit Definition

L5

Frame Relay Network

62 54 75 23

23L1

75L2

62L6

54

Permanent Virtual Circuit (PVC) MFS

End-user

SGSN

DLCI

23

Node-Z

Node-W

Routing table

L1/23 => L2/75

SGSN

End-user

MFS

DLCI

62

Node-X

Routing tableL2/75 => L5/54

Node-Y

Routing table

L5/54 => L6/62

t The MFS who wishes to send data to the SGSN, inserts DLCI=23 in the frame header.

t The first node (W), which receives this frame on the L1 link, examines its correspondence table and relays this frame on its L2 link making sure to assign the new DLCI=75 for this interface.

t The node X carries out the same operation and the frame is thus transmitted on the L5 link under the DLCI 54.

t Then the node Y carries out the same operation.

t Finally, User B receives this frame with a DLCI=62. It is able to identify the origin of this frame thanks to its DLCI calling part.





5.2 BSS / NSS Protocols and Software Modules

5.2.3 GPRS and EGPRS Protocols [cont.]Layer Model for Transmission plan (GPRS and EGPRS) (2)

Header Data

Header Data

LLC

PHYSICAL

CRC CRC CRCRLC MAC

IP/X25

SNDCP

Division of the SDU in 2 blocks

Compression of each part

Label added for each block

LLC EncapsulationCRC

RLC Encapsulation

LLC frame splittedinto blocks

Header

= < 1520 BytesHeader

Channel Coding

Block 1 Block 2 Block 3 Block 4 Block 5 Block 6 Block 7 Block 8

Block 1 Block 2 Block 3 Block 8

CRCHeader

Header

t Level 3: (Data)n SNDCP = SubNetwork Dependent Convergence Protocoln GTP = GPRS Tunneling Protocol

t For GPRS Traffic, the BSS is only used for LLC frame relay between the MS and the SGSN.n LLC = Logical Link Control

(provides a safe link, independent from the physical support)LLC frames carry user packets (inside SNDCP-PDU) or SGSN-MS signaling (GMM/SM).

n RLC = Radio Link Control.(provide a safe link, but independent from the physical support: ack, error ctrl and flow control adapted to GSM channels)

n MAC = Medium Access Control(Mapping of LLC frames on to GSM physical channels)

n BSSGP = BSS GPRS Protocol (Similar to BSSMAP)Functions:

– LLC frame relay without integrity guarantee(relay of the user data and the GMM messages: Paging and indications on Um status). Hides FR layers for LLC layer.

– SGSN-BSS signaling = Gb interface objects handling.– Management of cell-SGSN traffic: flow ctrl + unblock+reset, particularly

management of the cell update (in the same RA): the BSSGP header always indicates the serving cell. Therefore if the MS is ready and it is a new cell, then the SGSN stores this new cell and sends back to it (DL) all the unacknowledged LLC_PDU.

t The CRC is checked by the RLC/MAC layer but is generated by the physical layer.





2 GPRS Operation2.4 Basic Procedures

Um Gb Gn Gi

Application

IP

SNDCP

LLC

RLC

MAC

PhysicalLayer

MS

RLC

MAC

PhysicalLayer

BSS(with PCU)

(BSSGP)Framerelay

PhysicalLayer

GTP

UDP

IP

L2

PhysicalLayer

SNDCP

LLC

(BSSGP)Framerelay

PhysicalLayer

SGSN

IP

L2 (MAC)

PhysicalLayer

IP

GTP

UDP

IP

L2

PhysicalLayer

GGSN

Application

relay

relay

t Transmission plane

t GTP (GPRS Tunnelling Protocol) tunnels user data between GPRS Support Nodes in the backbone network. The GPRS Tunnelling Protocol shall encapsulate all PDP PDUs.

t UDP (User Datagram Protocol) carries GTP PDUs for protocols that do not need a reliable data link (e.g., IP), and provides protection against corrupted GTP PDUs.

t IP (Internet Protocol) is the backbone network protocol used for routing user data andcontrol signalling. The backbone network may initially be based on the IPv4. Ultimately, IPv6 shall be used.

t SNDCP (SubNetwork Dependent Convergence Protocol ) maps network-level characteristics onto the characteristics of the underlying network.

t LLC (Logical Link Control) provides a highly reliable ciphered logical link. LLC shall be independent of the underlying radio interface protocols in order to allow introduction of alternative GPRS radio solutions with minimum changes to the NSS.

t Relay. In the BSS, this function relays LLC PDUs between the Um and Gb interfaces. In the SGSN, this function relays PDP PDUs between the Gb and Gn interfaces.

t BSSGP (Base Station System GPRS Protocol) conveys routing and QoS-related information between the BSS and the SGSN. BSSGP does not perform error correction.

t (NS) Network Service transports BSSGP PDUs. NS is based on the Frame Relay connection between the BSS and the SGSN, and may - multi-hop and traverse a





3 The Base Station Subsystem3.3 Layered Model

BTS MFS SGSNMS

BSSGP

Gb

Physicallayer

Framerelay

RLC

MAC

RLC

Physicallayer

Framerelay

BSSGP

Um Abis/Ater

PCU

IP

LLC

GMMSM

relay

LLC

GMM SNDCPSM

relayPhysicallayer Physical

layerL2-GCHL1-GCH

L2-GCHL1-GCH

MAC

SNDCP

t User plane

t For GPRS TRAFFIC, the BSS simply relays the LLC frames between the MS and the SGSN.

t BSSGP = BSS Gprs Protocol. Functions:n to relay LLC frame over the Gb, with no guarantee of integrity (relaying user

data and GMM / SM messages : session, RA_update and paging procedures). Conceals the FR layers for the LLC layer.

n SGSN-MFS signaling = management of Gb interface objects (flush, paging, resume suspend, LLC-discarded and other procedures).

n cell-SGSN traffic management (identified by BssgpVCs): in particular cell update management (in the same RA): the BSSGP header always indicates the current cell so if a "ready" MS moves into a new cell, then the SGSN stores this new cell and sends all the unacknowledged LLC_PDUs to it (DL).

t The concept of handover has no meaning in packet switching (GPRS). There is no "circuit" to re-establish!

t RLC = Radio Link Control. (Provides a safe link for transporting LLC-PDUs in acknowledged or unacknowledged mode, LLC-PDU segmentation into blocks and reassembly, management of TBF contexts. RLC depends on the physical bearer: data encoding, error control and flow control suited to GSM channels.

t MAC = Medium Access Control. Multiplexing of RLC frames onto PDCH (transfer of blocks over the different PDCHi). Including traffic sharing over several TSs or, conversely, the use of one TS for several users.





NSE2

SGSN

NSE1NSE1

NSE2

F.RF.RNetworkNetwork

PCM

3 The Base Station Subsystem3.4 Gb Interface

PCM

PCM

BVCI=2

BVCI=1

BVCI=3

BVCI=5

BVCI=6BVCI=4

BSC1

BSC2

GPRS Core Network sideBSS side

BC PCMBCPVC

BC BCPVC

NSVC1

NSVC2

PCM

PCM

PCM

BC PCMBCPVC

BC BCPVC

NSVC3

NSVC4

BVCI=2BVCI=2

BVCI=1BVCI=1

BVCI=3BVCI=3

BVCI=5BVCI=5

BVCI=4BVCI=4

BVCI=6BVCI=6

t Managed entities







t RLC = Radio Link Control. (Provides a safe link for transporting LLC-PDUs in acknowledged or unacknowledged mode, LLC-PDU segmentation into blocks andreassembly, management of TBF contexts. RLC depends on the physical bearer: data encoding, error control and flow control suited to GSM channels.






3 The Base Station Subsystem3.4 Gb Interface

GPRS Core Network sideBSS sidet Protocols

SGSNPacket Control Unit function(PCU)

BSS GPRS Protocol(BSSGP)

BSS GPRS Protocol(BSSGP)

Network Service Control(NSC)

Network Service Control(NSC)

BVCI=2

BVCI=1

BVCI=3

BVCI=5

BVCI=6BVCI=4

BSC1

BSC2

Sub-Network Service(SNS)

Physical layer

Sub-Network Service(SNS)

Physical layer

Frame Relay

BVC

NS-VC

NSE

PVC

PCM PCM

BC







t RLC = Radio Link Control. (Provides a safe link for transporting LLC-PDUs in acknowledged or unacknowledged mode, LLC-PDU segmentation into blocks and reassembly, management of TBF contexts. RLC depends on the physical bearer: data encoding, error control and flow control suited to GSM channels.






networkMS

startof TBF1 end of

TBF1TBF2 TBF3 TBF4

timefULi

Packet Channel Request

Packet Resource Assignment (list of PDCHi, token=T,TFIk)

MS starts listening to all DL blocks token value on the allocated PDCHi

SEND on block b+1 (TFIk)

in block b token =T ?

Y

N

MFS

Ø Ø T T Ø T Ø T T T ØDL PDCHi

? Ø Ø TFIk TFIk Ø TFIk Ø TFIk TFIk TFIkUL PDCHi

3 The Base Station Subsystem3.5 Radio interface

t UL transfer

t This slide demonstrate that the radio resources (blocks) are used only when data need to be transferred (LLC-PDU) : dynamic radio resource allocation. As a matter of fact, an MS shall specify its radio resource request at initiation of each TBF for a better optimization of radio resource & MS capabilities.

t A TBF (the blue shape) comprises one or more consecutive LLC-PDUs.

t Temporary (Block) Flow Identity = TLLI + sequential number, used by the network to recognize data from different MSs. Identifies uniquely a TBF in one direction within a cell.n The blocks are dynamically allocated upon the use of a token (Uplink State

Flag) allocated to the MS at TBF establishment. Any DL block includes a USF in the header.

n The mobile "listens" to the PDCHi assigned, when block b (in DL) contains USF = T, the MS shall send one PDTCH in UL on block b+1 on the UL PDCHi.

t The theoretical maximum of 160 kbit/s is given for one MS which would have 8 PDCHs of 21.4 kbit/s each. Those MS are yet to be available on the market place.





PS PagingPaging Request ("packet")

Packet Paging Response

Packet Resource Assignment (list(PDCHj),TFIz)

The MS consumes the content of block b

in block b, TFI=TFIz ?

Y

N

MFS SGSN

UL TBF: refer toprevious slide

MS PDU

MS starts listening to all DL blocks TFI value on the allocated PDCHj

Ø Ø Z Z Ø Z Ø Z ZDL PDCHj

3 The Base Station Subsystem3.5 Radio interface

t DL transfer

t In DL, each time an LLC-PDU is received, if there is no TBF in progress, it is essentialto “establish" one.

t To respond to the paging, the MS needs to send a "paging response" to the SGSN (GMM) encapsulated in an LLC_PDU. This response is carried by an UL TBF.

t Upon reception of the Paging response, the SGSN can send the DL PDU (LLC frame) to the MS through the MFS.The MFS shall establish a DL TBF with the MS.

t DL TBF: each block of the DL TBF are identified by the DL TFI = TFIzt After completion of the TBF establishment phase, the MS listen to all the DL blocks on

the allocated PDCHs and keeps the blocks tagged with the TFIz.





IMT

@1.1.1.50 @2.2.2.50

JBGPU slot [email protected] @2.2.2.51

JBGPU slot [email protected] @2.2.2.65

JBGPU slot 21

To A-GPSserver

PSDN

To OMC-RI/O LAN

@1.1.1.20 Sub@10002 Sub@10003

9 1 13 20

24 23 21 22

1 13 20 9

21 22

LSN 2

@1.1.1.1 @2.2.2.1

@192.1.5.33

@1.1.1.2 @2.2.2.2

@192.1.5.34

Serv

er A

@1.1.1.10 @2.2.2.10

External router

@192.1.5.33 / @[email protected]

External hub or intranet

3 Com

SUPERSTACK

1 2 3 4 5 6 7 813 14 15 16 17 18 19 20

Tcvr1Tcvr2

Port Status

9 10 11 1221 22 23 24

100 Mbps10 Mbps

Power/Self testMgmt/Attn

Segment

3 Com

SUPERSTACK

1 2 3 4 5 6 7 813 14 15 16 17 18 19 20

Tcvr1Tcvr2

Port Status

9 10 11 1221 22 23 24

100 Mbps10 Mbps

Power/Self testMgmt/Attn

Segment

POWER

AUI10BASE210BASE-T

1 2 3 4 5 6 7 8

Tx

Rx

POWER

IOLAN+RackSerial Server

perle

POWER RPS ACTIVITY

RS232

LSN 1

@ 1.1.1.30

JBETI slot 4JAETI

@ 1.1.1.31

JBETI slot 23JAETI

RS232

1 2 3 4 5 6 7 8

1 2 3 4 5 6 7 8 Partition

LinkMDI-X

MDI-X/MDIPower

Data<Data>

On Line

Col

NM C

AUI Part

Fault AUI

Serv

er B

3 MFS Ethernet Architecture 3.1 Ethernet Architecture and IP addressing

t 3 MFS ETHERNET ARCHITECTUREn JBGPU boards are connected to Hubs 1 and 2 through the BATTU boards. The

JBGPU board in slot 6 is connected to port 1, slot 7 to port 13 and so one.n Each JAETI applique is directly connected to port 9 of one hub. n Each server is connected to both hubs f. There is an IP connection between each

server to an external hub or to an intranet for the connection to the OMC-R.n The IOLAN is used to access the RS232 port of each server. It is connected to

hub1 only.n The IMT is connected to hub1 only.

t IP addressingn They are given during the MFS commissioning.n The floating address is used to access the active server from OMC-R.n To display the addresses of the board:

– Open Telnet session on a server.– Enter arp -a.





t Reminder: all MFS connection possibilities

7.2 MFS Evolution connection modes

Summary





t Direct connection for Gb

Dedicated or mixed Ater link


Standard connection with dedicated or mixed Ater link





t Gb interface connection through the transcoder and MSC (TC transparency)


TC transparency (Gb interface through A interface)





third rack

4 Alcatel Solution 4.3 SGSN Packet Switched Core Network

Screen KeyboardKVM Switch

NS500

NS500

Firewall Server

external DNS

NTS150NTS150 NTP Server

PLMNDNS/DHCP

LAN Gi Gp

BG, Access Router

second rack

LANIO/Gnswitches

Non-pilotservers

SGSN/GGSNrouters

first rack

LSN Ethernetswitches

GPU

CCS N7

pilotservers

t Compacted configuration racks

t The E configuration is the smallest one available. It can be software-blocked to 25K, 50K or 75 K MM contexts. Above, the configuration with co-located GGSN.

nEquipment QuantitynCMIC couplers 2 to 4nGPU boards 2 to 6nGb PCM links Up to 96nDS10 servers 4 (2 Pilots et 2 non Pilots with SS7 adapter)nShared Disks 2x18 GbytesnRouters 2 or 3

t G configuration is the largest one available.nEquipment QuantitynCMIC couplers 2 to 4nGPU boards 8nGb PCM links 128nDS10 servers 12 to 14 (2 Pilots, 10 to 12 Non Pilots with SS7 adapter)nShared Disks 2x18 GbytesnRouters 2 or 3

t Power Supply:n48V DC by a Top Rack Unit inside Each rack (GPU sub-rack, Fans, CMIC sub-rack, SGSN router).n230V AC in Direct Link for each Non Pilot DS10, secured link for the Pilot DS10, Fast Ethernet Switches and RS232 concentrators.

t The GPU redundancy functionality is not provided in Release 2





4.1 Configurations and Boards LocationBSC configurations

t Rack Layout, maximum Configuration (conf. 6):n Smaller configurations consist of less racks or half-filled racks

AIRBAFFLE

A-BIS TSUGS

GSCOMMON TSUTSCA

ClockStage 1

Stage 2Stage 2 Stage 2Group Switch GS GS

A-TER TSU A-TER TSU

A-BIS TSU

A-BIS TSU

A-TER TSU

A-BIS TSU

Stage 2

A-BIS TSU

AIRBAFFLE

A-BIS TSUGS

GSA-BIS TSUTSCA

ClockStage 1

Stage 2Stage 2 Stage 2

A-BIS TSU

Group Switch GS GS

A-TER TSU

A-TER TSU A-TER TSU

A-BIS TSU

Stage 2

A-BIS TSU

AIRBAFFLE

A-BIS TSUGS

A-BIS TSUTSCA

ClockStage 1

A-BIS TSU

A-TER TSU

A-TER TSU A-TER TSU

A-BIS TSU

Conf 1

Conf 2

3

4

5

6

t For a detailed description of each rack, see appendix.





t Function of the DTCC according to its location

S4: BSC configurationsDTCC function mapping

Rack 1 Rack 2 Rack 3

A-BISGS 1

GS 2COMMON TSUTSCA

Clock

A-BIS

A-BIS A-BIS

N7

N7

SCCP

TCHRM

TCHRM

SCCP

SCCP

SCCP

SCCP

TCHRM

TCHRM

SCCP

SCCP

SCCP

N7

N7

N7

N7

SCCP

SCCP

SCCP

SCCP

SCCP

SCCP

GS 2 GS 2 GS 2

A-BISGS 1

GS 2TSCA

Clock

A-BIS

A-BIS A-BIS

N7

N7

SCCP

TCHRM

TCHRM

SCCP

SCCP

SCCP

SCCP

TCHRM

TCHRM

SCCP

SCCP

SCCP

N7

N7

N7

N7

SCCP

SCCP

SCCP

SCCP

SCCP

SCCP

GS 2 GS 2 GS 2

A-BIS

A-BISGS 1

TSCA

Clock

A-BIS

A-BIS A-BIS

N7

N7

SCCP

TCHRM

TCHRM

SCCP

SCCP

SCCP

SCCP

TCHRM

TCHRM

SCCP

SCCP

SCCP

N7

N7

SCCP

SCCP

SCCP

SCCP

SCCP

SCCP

SCCP

SCCP

A-BIS

AterMux1 AterMux2 AterMux3 AterMux4

AterMux5 AterMux6


AterMux11 AterMux12


AterMux17 AterMux18





313131

SN7

31

0

SN7SN7

31

0

00

X2531

X25

N7Alarm byte

Qmux

0

1415

16

31

0

A-ter Mux (1 or 2)A-ter A

4.4 A, A-ter, A-ter Mux Time Slot Mapping Principle

31

141516 N7

141516 N7

141516

31

SN7

31

SN7

31

SN7

31

141516

141516

ASMB MT120

31

141516

31

141516

31

141516

0

00

X25

1

2

4

3

X X X XX XX X

t This figure gives the principle of the A, A-ter multiplexing / demultiplexing in A-ter Mux interface for the A-ter Mux1 and 2 of one BSC

t For the other A-ter Mux (3 to 6) it is the same mapping with out X25 and Qmuxchannels .These are used for traffic channels

t Alarm byten In the alarm byte, 2 bits are used for each tributary

– AI alarm indication– RI remote alarm indication state

n Alarm byte status from MT120 to BSC– The alarm byte is always sent with no alarm state : Advantage being in

case of MSC reset to avoid any huge flow of blocking messages from BSC and to simplify alarm reporting from MT120

n Alarm byte status from BSC to MT120– In case of a reception of an AI bit set to “one”, an AIS is inserted to MSC

on A interface– In case of a reception of an RI bit set to “one”, an RAI is inserted to MSC

on A interface

t AMR (Adaptive Multi Rate) is a technology defined by ETSI which relies on two extensive sets of “codec modes”. One has been defined for FR and one for HR. When used in combined FR and HR mode, AMR brings a new answer to the trade-off between capacity and quality:

– Speech quality is improved, both in full-rate and half-rate,– Offered capacity is increased due to the provision of half-rate channels

allowing to densify the network with low impact on speech quality.





6. BSS Interfaces

A, Ater, Ater Mux Interfaces

t Ater Mux: MFS-TC – Indirect GB = TC transparency

t In this configuration there is granularity of 25 % which means 3/4 GSM & 1/4 (E)GPRS





2 How Does It Work?

CCCH Direction

t Can you determine the direction of the 3 channel types carried on a CCCH?Select the correct answer for each channel.

Mobile

Base Station

RACH

AGCH

PCH

CCCH





5 MFS Interfaces5.1 MFS - MS Physical Interfaces

t Control Plane / Without Master PDCH

GSL n x 64 Kbit/s(LAPD)

BSCBTS

AterMuxAbisUm

GPU

Paging RequestBSC Load

Channel RequestPDCH allocation

RSL 64 Kbit/s(LAPD)

BCCH

Paging Request

t Um interfacen The Um interface is located between the MS and the BTS. It is sometimes called

Air or Radio interface. It is used for both CS and PS traffic. The BSC is in charge of allocating radio resources on the Um interface.

t Abis interfacen The Abis interface is located between the BTS and the BSC. It is used for both

CS and PS traffic. The BSC is in charge of allocating Abis transmission resources. 16 Kbit/s channels are used for data transmission.

n The Abis interface can support 2 physical links (Primary Abis link and Secondary Abis link). They allow to use GPRS with CS-1 to CS-4, and EGPRS with MCS-1 to MCS-9 (if TRE capable).

n The signaling messages are carried on dedicated 64 Kbit/s channels, called Radio Signaling Links (RSLs).

t AterMux interfacen The AterMux interface is located between the BSC and the MFS. When used for

both CS and PS traffic, the interface is called AterMux (for multiplexed AterMux), and only 16 Kbit/s channels, called GPRS CHannels (GCHs) can be allocated.

n The signaling messages are carried on up to 4 dedicated 64 Kbit/s channels (at least one), called GPRS Signaling Links (GSLs).

t Gb interfacen The Gb interface is located between the MFS and the SGSN. The Gb physical

interface consists of one or more 64 Kbit/s time slots. They can be carried by the MFS-SM/TC Atermux interface or by direct 2048 Kbit/s links to the SGSN.





MPDCH

PBCCHPBCCHPCCCH = PPCH + PAGCH + PRACHPCCCH = PPCH + PAGCH + PRACH

PTCH = PDTCH + PACCHPTCH = PDTCH + PACCH

PDCH

SPDCH PDCH = PDTCH + PACCHPDCH = PDTCH + PACCH

3 The Base Station Subsystem 3.5 Radio interface

t Master and Slave PDCHs

t For each cell, it is possible to define the MINIMUM and MAXIMUM number of channels reserved for GPRS + the maximum number of channels reserved for GPRS in case of high traffic load (when the BSC sends "Load indication" to the MFS through BSCGP protocol).

t There are two types of PDCH : MPDCH and SPDCHn MPDCH = Master PDCH = PBCCH + PCCCH (PPCH + PAGCH + PRACH) ->

carries GPRS signaling and system information.n SPDCH = Slave PDCH -> carries the user traffic.

t Benefits of the Master Channel :n Preserves CCCH capacity for speech servicesn Higher GPRS signaling capacity, in line with GPRS traffic growthn Differentiated cell re-selection strategy between GPRS and non GPRS MS. When

GPRS attached, a MS listen to PSI broadcast on PBCCH. It allows a finer tuning of GPRS re-selection algorithms, for example in hierarchical networks (C31 and C32 criteria). Otherwise, MS applies the basic Cell-reselection as in GSM Idle-Mode using the C1 and C2 GSM criteria





Gb interfacePermanent Virtual Circuit Definition

L5

Frame Relay Network

62 54 75 23

23L1

75L2

62L6

54

Permanent Virtual Circuit (PVC) MFS

End-userSGSN

DLCI23

Node-Z

Node-W


SGSN

End-userMFS

DLCI62

Node-X


Node-Y


t The MFS who wishes to send data to the SGSN, inserts DLCI=23 in the frame header.

t The first node (W), which receives this frame on the L1 link, examines its correspondence table and relays this frame on its L2 link making sure to assign the new DLCI=75 for this interface.

t The node X carries out the same operation and the frame is thus transmitted on the L5 link under the DLCI 54.

t Then the node Y carries out the same operation.

t Finally, User B receives this frame with a DLCI=62. It is able to identify the origin of this frame thanks to its DLCI calling part.





Gb interfaceGb Logical Presentation

NS-VCI 1

NS-VCI 3

NSEI = 1, Load sharing

MFS Frame Relay SGSN

BVCI = 0

BVCI = 2Cell id8

BVCI = 3Cell id3

BVCI = 4Cell id9

BVCI = 5Cell id7

BVCI = 0

BVCI = 2

BVCI = 3

BVCI = 5

BVCI = 4

PVC 1(DLCI = 34)

PVC 2(DLCI = 98)

Bearerchannel

3

NS-VCI 1

NS-VCI 3

Bearerchannel

1

PVC 1(DLCI = 16)

Bearerchannel

2

PVC 2(DLCI = 17)

FrameRelay

network

t Bearer channel (BC)n A BC is an n x 64 Kbit/s link which supports a Permanent Virtual Circuit (PVC).

t Permanent Virtual Circuit (PVC)n A Frame relay PVC allows the service of multiplexing on a BC. One PVC is

associated with one NS-VC. A PVC is identified by its Data Link Connection Identifier (DLCI), which is independent from the one defined at the SGSN side. There is a dedicated DLCI (DLCI=0) used for the FR to support signaling functions (it is not a PVC).

t Network Service Virtual Connection (NS-VC)n In order to provide an end-to-end communication between the MFS and the

SGSN irrespective of the exact configuration of the Gb interface, the concept of NS-VC is used.

n The NS service is in charge of managing the load sharing.n The peer-to-peer communication between the MFS and SGSN is performed

over NS-VCs.n Each NS-VC is identified by means of an NS-VC Identifier (NS-VCI) having an

end-to-end significance across the Gb interface. NS-VCs are configured by O&M.

n In the Alcatel BSS, there is a one-to-one mapping between one NS-VC and a one FR PVC.

t Network Service Entity (NSE)n The Network Service Entity Identifier (NSEI) is an end-to-end identifier. It is

unique within the SGSN. At each side of the Gb interface, there is a one-to-one correspondence between an NSVC and an NSEI.

n An NSE is associated to a set of BVCs.The NSE maps a set of BVCs and an NS-VC.





A9130 BSC Evolution configuration and performance in B9





t Radio Access Network Overview

9135 MFS 9130 BSC/MFS





A9130 BSC Evolution configuration and performance in B9





MxBSC Software Architecture From G2BSC to MxBSC

T C U C

T C U C

T C U C

T C U C

T C U C

T C U C

T C U C

T C U C

A S

D TC C

D TC C

D TC C

D TC C

D TC C

D TC C

D TC C

A S

D TC C

C P R C C P R C C P RC C P RC C P R C C P R C C P R C C P R C

AS

6 xG.703AbisI/F

2 xG .703Aterm uxedI/F

Abis TSU Ater TSU

Common Functions TSU

G roup Switch8 Planes2Stages

TSL

ASM B

ASM B

Q 1 bus

Broadcast bus

TS C A

B IU A

OMCPOMCP

SSWSSW

CCPCCP

TP & LIU ShelfTP & LIU Shelf

• No more CPR broadcast: the feature is emulated.

• DTC TCH-RM does not manage Ater anymore and are moved on OMCP.

t Les DTC TCH-RM ne gèrent plus de lien Ater et ont été déplacés dans l’OMCP.

t Les CPR broadcast sont poubellisées





1 TCU = 32 OBCI1 FR TRE = 8 OBCI

1 DR TRE = 16 OBCI1 EXTS = 4 OBCI

⇓1 TCU = 4 FR TRE1 TCU = 2 DR TRE

1 TCU = 8 EXTS

MxBSC Functional improvementsMxBSC: No impact of EDGE on BSC connectivity

G2BSC

BIUA ASMB

TCU

Switching

DTC

Abis Ater

SignalingSignaling

Telecom TrafficTelecom Traffic

With G2 BSC the CS and the PS traffics goes through the TCU and DTC

MxBSC

CCP

TP

TCU DTC

Abis Ater

SignalingSignaling

Telecom TrafficTelecom Traffic

With MX BSC the CS and the PS traffics are switched inside the TP





t Shelf Geographic address





JBX

TPJB

XTP

JBX

CCP

JBX

CCP

JBX

OM

CP

JBX

OM

CP

JBX

SSW

JBX

SSW

t ATCA shelf physical and logical address.JB

XTP

JBX

TP

JBX

CCP

JBX

CCP

JBX

SSW

JBX

SSW

JBX

CCP

JBX

CCP

JBX

CCP

JBX

CCP

13 11 9 7 5 3 1 2 4 6 8 10 12 14 Logical @

Physical slot1 2 3 4 5 6 7 8 9 10 11 12 13 14

JBX

OM

CP

JBX

OM

CP F

ILLER

Front view of the ATCA shelf with a 600 TRX configuration BSC

5.2 Internal IP addresses in the A9130 BSC

Internal IP addresses in the A9130 BSC

FILLER

FILLER

FILLER

t The logical slot are written on the ATCA shelf for purpose maintenance.





7.1 A9130 BSC configuration

Stand Alone configuration

t The BSC Evolution stand alone configuration consists of one rack dedicated for one BSC

LIU Shelf 1(BSC)

LIU Shelf 2none

ATCA Shelf 3(BSC)

Shelf 4none

PDU

Rules:A single BSC is always installed withShelf 3 dedicated to ATCA shelf, and shelf 1 dedicated to LIU shelf

BSC stand alone

t Rules are applied for shelf positions regarding to weight, security stability constraints and logistics benefit.

t As BSC stand alone, it exists also a MFS stand alone configuration which is:t Either called « MFS 9 GP stand alone » . The cabinet is composed of 1ATCA shelf 3

and one LIU (shelf 1), t Or called « MFS 21 GP stand alone ». The cabinet is composed of 2 ATCA shelves

(shelf 3 and 4) and one LIU shelf (shelf1).The whole cabinet is seen as one single network element.





7.1 A9130 BSC configuration

Rack shared configuration

t The BSC Evolution rack shared configuration consists of one rack shared between 2 BSCs or between one MFS and one BSC.

LIU Shelf 1(BSC1)

ATCA Shelf 3(BSC1)

PDU

2 x BSC rack shared

LIU Shelf 2(BSC2)

ATCA Shelf 4(BSC2)

LIU Shelf 1(BSC)

ATCA Shelf 3(BSC)

PDU

BSC-MFS rack shared

LIU Shelf 2(MFS)

ATCA Shelf 4(MFS)

LIU Shelf 2(BSC)

ATCA Shelf 4(BSC)

PDU

BSC-MFS rack shared

ATCA Shelf 4(MFS)

LIU Shelf 1(MFS)

t Rules are applied for shelf positions regarding to weight, security stability constraints and logistics benefit.

t The « BSC rack shared» configuration which is composed of two shelves is also called a « BSC double capacity » because of two independant Network Elements.





7.2 A9130 BSC capacity

BSC capacities in terms of boards

t The BSC capacity is defined according to the number of TRXs

200 TRX 400 TRX 600 TRX

BSC Capacity

ATCA shelf

CCP

Spare CCP

TPGSM

OMCP

SSW

LIU shelf

MUX

LIU

1 2 3

1

1

2

2

2

1

2

8 16

Equipment

B9B10

4 5

800 TRX 1000 TRX

t The quantity of TPGSM, OMCP, SSW and MUX boards have to be considered as 1 active + 1 stand-by for redundancy function in the shelf.






Capacity and dimensioning for E1 links

t The BSC Evolution is able to process up to 2600 erlangs

200 TRX 400 TRX 600 TRX

BSC Capacity

Max number of BTS

Max number of cells

Total number of E1

Number of Abis

Number of Atermux CS

Number of Erlangs

Traffic Ater PS (Mb/s) Max

255

Equipment

Number of Atermux PS

264

224

176

30

18

2600

36

255

264

128

96

20

12

1800

24

150

200

112

96

10

6

900

12

14%Abis E1s / Total E1s 20%25%






Abis and atermux allocation on LIU boards

t Abis and atermux allocation on LIU boards versus BSC capacity

200 TRXLIU 1 LIU 2 LIU 3 LIU 4 LIU 5 LIU 6 LIU 7 LIU 8 LIU 9 LIU 10 LIU 11 LIU 12 LIU 13 LIU 14 LIU 15 LIU 16

1 1 17 33 49 65 81 97 113 129 145 161 41 31 21 2 12 2 18 34 50 66 82 98 114 130 145 162 42 32 22 4 33 3 19 35 51 67 83 99 115 131 147 163 43 33 23 6 54 4 20 36 52 68 84 100 116 132 148 164 44 34 24 8 75 5 21 37 53 69 85 101 117 133 149 165 45 35 25 10 96 6 22 38 54 70 86 102 118 134 150 166 46 36 26 12 117 7 23 39 55 71 87 103 119 135 151 167 47 37 27 14 138 8 24 40 56 72 88 104 120 136 152 168 48 38 28 16 159 9 25 41 57 73 89 105 121 137 153 169 x 39 29 18 1710 10 26 42 58 74 90 106 122 138 154 170 x 40 30 20 1911 11 27 43 59 75 91 107 123 139 155 171 x 24 18 12 1112 12 28 44 60 76 92 108 124 140 156 172 x 23 17 10 913 13 29 45 61 77 93 109 125 141 157 173 28 22 16 8 714 14 30 46 62 78 94 110 126 142 158 174 27 21 15 6 515 15 31 47 63 79 95 111 127 143 159 175 26 20 14 4 316 16 32 48 64 80 96 112 128 144 160 176 25 19 13 2 1

Abis ports ( max 176)Atermux CS ( max 48)Ater mux PS ( max 28)

200 TRX400 TRX 400 TRX

600 TRX 600 TRX

200

400

400

200

Abis portsAter Ports

600 TRX = 1.33 x 448 TRX

1000 TRX = 2,21 x 448 TRX

1

96

1

96

1

176

10

6 12 18

20 30

200 TRX

400 TRX

600 TRX

Abis Abis AbisCS/PS

PS

CS/PS

PS

CS/PS

PS

Atermux Atermux Atermux

LIU 14 LIU 15 LIU 1621 2 122 4 323 6 524 8 725 10 926 12 1127 14 1328 16 1529 18 1730 20 1948 42 4147 40 3946 38 3745 36 3544 34 3343 32 31

200 TRX400 TRX

600 TRX

200

400

400

200

t LIU boards are fitted in the LIU shelf depending on the BSC configuration (Capacity + connectivity), but

t only 2 HW configurations for the LIU shelf are considered: one with 8 LIU boards, one with 16 LIU boards,

t Assignment to each LIU boards either to Abis or Ater,t On average, 1 Ater LIU board is needed for 200 TRX,t On the Ater LIU, 10 TP are “generic” (can be assigned either to PS, full CS or a

mixed of the 2), and the 6 others are dedicated to PS.

t In case of 200 TRX configuration, Alcatel decided to split the traffic up to 2 LIU boards (even if one LIU board should be efficient) in order to not impact all the traffic in case of one LIU board failure.

t The maximum of available LIU boards are used for Abis, to offer maximum flexibility to the clients.

t The port numbered 9, 10, 11 and 12 on the LIU 12 are not used.





Annex T

CP Log mapping

t In order to allow communication between VCE of one board but also VCE located on another board it is neccessary to have a routing table which contains the address of each VCE. This routing table is located in each CMW.

t Proc_ name: is the identification of the process related to intra or inter boardcommunication, means the logical identification of a VCE.

t CP-LOG: is the logical aspect with a group of VCEs mapped.t The mapping between VCEs and CP-LOG is determined according the BSC

configuration type.t CP-HW: is the physical CP which represent CCP, OMCP or TPGSM board.t IP-@ : is the IP address of the board.

t Exercise: 3 – With the help of Annex T can you retrieve the VTCU/VDTC number managed by the CP log 3 ?





2.10 MFS synchronization modes

Autonomous synchro.: 12 or 16 E1s per GP – No Gaps

t One shelf extensible : 12x9 =108 E1

t or 2 shelves : 12E1 x 21 GP= 252 E1 max

t

t

t

t One shelf not extensible :t 16 E1 x 8 GP= 128 E1 max

LIU 1 LIU 2 LIU 3 LIU 4 LIU 5 LIU 6 LIU 7 LIU 8 LIU 9 LIU 10 LIU 11 LIU 12 LIU 13 LIU 14 LIU 15 LIU 161 0 16 32 48 64 80 96 112 128 144 160 176 192 208 224 2402 1 17 33 49 65 81 97 113 129 145 161 177 193 209 225 2413 2 18 34 50 66 82 98 114 130 146 162 178 194 210 226 2424 3 19 35 51 67 83 99 115 131 147 163 179 195 211 227 2435 4 20 36 52 68 84 100 116 132 148 164 180 196 212 228 2446 5 21 37 53 69 85 101 117 133 149 165 181 197 213 229 2457 6 22 38 54 70 86 102 118 134 150 166 182 198 214 230 2468 7 23 39 55 71 87 103 119 135 151 167 183 199 215 231 2479 8 24 40 56 72 88 104 120 136 152 168 184 200 216 232 24810 9 25 41 57 73 89 105 121 137 153 169 185 201 217 233 24911 10 26 42 58 74 90 106 122 138 154 170 186 202 218 234 25012 11 27 43 59 75 91 107 123 139 155 171 187 203 219 235 25113 12 28 44 60 76 92 108 124 140 156 172 188 204 220 236 25214 13 29 45 61 77 93 109 125 141 157 173 189 205 221 237 25315 14 30 46 62 78 94 110 126 142 158 174 190 206 222 238 25416 15 31 47 63 79 95 111 127 143 159 175 191 207 223 239 255

Exemples for 3 configurations for 4, 9, and 21 GPUsColors shown affectation of LIU per GPU

GPU 1, 5, 9, 13, 17, 21GPU 2, 6, 10, 14, 18GPU 3, 7, 11, 15, 19GPU 4, 8, 12, 16, 20

21 x GPU9 x GPU

t One Shelf Extensible / Two Shelves Configuration (Autonomous synchronization)

t The number of LIU ports (E1 links)/GP is as follows:t 12 LIU ports per GP to get maximum number of 9 GP in an MFS (one shelf)t 12 LIU ports per GP to get maximum number of 21 GP in an MFS (two shelves)

t Also called “Stand-alone (Autonomous)” configuration because no BSC presence is forecasted

t One Shelf Not Extensible Configuration (Autonomous synchronization)t The number of LIU ports (E1 links)/GP is as follows:t 16 LIU ports per GP to get maximum number of 8 active GP in a MFS with 8 GP maximumt Also called “Rack shared (Autonomous)” configuration because a BSC can be installed in the future





2.10 MFS synchronization modes

Centralized synchro.: 12-2 or 16-2 E1s per GP : Gaps

t -17% of E1s:t One shelf extensible :10x9=90 E1

t or 2 shelves : 10 x 21 = 210 E1

t

t One shelf not extensible :t 14 E1 x 8 GP= 112 E1 max (- 12.5 %)

LIU 1 LIU 2 LIU 3 LIU 4 LIU 5 LIU 6 LIU 7 LIU 8 LIU 9 LIU 10 LIU 11 LIU 12 LIU 13 LIU 14 LIU 15 LIU 161 0 16 32 48 64 80 96 112 128 144 160 176 192 208 224 2402 1 17 33 49 65 81 97 113 129 145 161 177 193 209 225 2413 2 18 34 50 66 82 98 114 130 146 162 178 194 210 226 2424 3 19 35 51 67 83 99 115 131 147 163 179 195 211 227 2435 4 20 36 52 68 84 100 116 132 148 164 180 196 212 228 2446 5 21 37 53 69 85 101 117 133 149 165 181 197 213 229 2457 6 22 38 54 70 86 102 118 134 150 166 182 198 214 230 2468 7 23 39 55 71 87 103 119 135 151 167 183 199 215 231 2479 8 24 40 56 72 88 104 120 136 152 168 184 200 216 232 248

10 9 25 41 57 73 89 105 121 137 153 169 185 201 217 233 24911 10 26 42 58 74 90 106 122 138 154 170 186 202 218 234 25012 11 27 43 59 75 91 107 123 139 155 171 187 203 219 235 25113 12 28 44 60 76 92 108 124 140 156 172 188 204 220 236 25214 13 29 45 61 77 93 109 125 141 157 173 189 205 221 237 25315 14 30 46 62 78 94 110 126 142 158 174 190 206 222 238 25416 15 31 47 63 79 95 111 127 143 159 175 191 207 223 239 255

Exemples for 3 configurations for 4, 9, and 21 GPUsColors shown affectation of LIU per GPU

GPU 1, 5, 9, 13, 17, 21GPU 2, 6, 10, 14, 18GPU 3, 7, 11, 15, 19GPU 4, 8, 12, 16, 20

21 x GPU9 x GPU

•Gaps are mandatory for clock propagation

•Gaps are mandatory for clock propagation

t One Shelf Extensible / Two Shelves Configuration (Centralized synchronization)

t The number of LIU ports (E1 links)/GP is as follows:t 10 LIU ports per GP to get maximum number of 9 GP in an MFS (one shelf)t 10 LIU ports per GP to get maximum number of 21 GP in a MFS (two shelves)

t Also called “Stand-alone (Centralized)” configuration because no BSC presence is forecasted

t One Shelf Not Extensible Configuration (Centralized synchronization)t The number of LIU ports (E1 links)/GP is as follows:t 14 LIU ports per GP to get maximum number of 8 active GP in a MFS with 8 GP maximumt Also called “Rack shared (Centralized)” configuration because a BSC can be installed in the future





t MFS Evolution Capacity and performances

(*) 2 E1 are reserved for the GP synchronisation in case of centralized mode

Nota : from 9 GP in MFS Evolution, only 12 E1 is applicable on B8 MR6/7 and B9 MR1 ed6 , GP board (A9130 MFS Evolution) capacity is equal to the GPU board on MFS A9135 (legacy).

t Increase of capacity compared to the legacy is available with B9 MR4

A9130 MFS EvolutionEvolution & Introduction

reminder

Max number of PDCH per GP (A9130)B8 / B9 MR1 ED6

GP configuration max nbr PDCH (*) 12 E1(*)/board 16 E1(*)/boardGPRS CS2 240 960 960

CS3 220 864 892CS4 204 660 804

EGPRS MCS1 232 856 856MCS2 228 836 836MCS3 212 796 796MCS4 200 720 772MCS5 180 584 704MCS6 172 460 660MCS7 140 312 448MCS8 116 264 380MCS9 108 244 348

B9 MR4





6. BSS Interfaces

Abis Interfacet Submultiplexing OML and RSL:t The OML can be mapped on a 64 Kbit/s Time Slot:

t There are four Signaling Link Multiplexing rules options :n No RSL multiplexing : the RSL is mapped on a 64 Kbit/s Time slot.

n Static RSL multiplexing : 1 RSL is mapped on a nibble (a quarter of Time Slot) at 16 Kbit/s

n Statistical RSL multiplexing at 64 Kb/s: 1 OML and up to 4 RSL share the same physical channel at 64 Kbit/s

n Statistical RSL multiplexing at 16 Kb/s : 1 OML and 1 RSL share the same physical channel at 16 Kbit/s

t The signalling submultiplexing offers improvement in terms of required PCM time slots on the A-bis interface. This leads to substantial savings in terms of A-bisinterface trunks.

t Hardware support :Alcatel 9120 BSC (G2), Alcatel 9100 BTS, Alcatel 9110 BTS, Alcatel 9110-E BTS

t Remarks: t For an Evolium BTS, transmission configuratoion must be done via OML. The

Evolium BTS retrieves autonomously its OML location by scanning the 31 TSs of the PCM link.

t The static RSL multiplexing is not compatible with Half Rate configurations (RSL capacity)





t SDCCH congestion measurement:

t L1.18 Type 7 : LapD measurements Counter Name : TIME_LAPD_CONG

t “110 counters” only measure SDCCH congestion without being able to correlate it with LapD/RSL congestion.

Nota: 16 TRE in a concentric cell on 1 Abis, RSL MUX scheme = 16k statistic, high risk of SDCCH congestion + impossibility to perform HR

Increase of capacity but SDCCH throughput reduced from 64k to 16k

SDCCH and Lapd/RSL congestion

Info





Capacity ModeOverview

n 1 TWIN module = 2 functional TRX = 16 radio timeslotsn The 2 TRX can belong to different sectors

(Twin TRX sharing).n 4 RX diversity not possible (only 2 RX div)n Up to 24 TRX in MBI5/MBO2 cabinets

Tx : GSM 900 : 45 W GMSK / 30 W 8PSK = TRAGHEGSM 1800 : 35 W GMSK / 30 W 8PSK = TRADE

Rx : Sensitivity : -114.5 to – 117 dBm (*) (2 RX div)(*) environment dependent

Tx : GSM 900 : 45 W GMSK / 30 W 8PSK = TRAGHEGSM 1800 : 35 W GMSK / 30 W 8PSK = TRADE

Rx : Sensitivity : -114.5 to – 117 dBm (*) (2 RX div)(*) environment dependent

TRX1

TRX2

Reduced power consumptionSaving per TRX:-17% in GSM900-35% in DCS1800

Reduced power consumptionSaving per TRX:-17% in GSM900-35% in DCS1800

t TWIN in capacity mode is equivalent to two MP TRXs with 2Rx div





Rx : Equ. sensitivity = -117.4 to - 121 dBm (*) (4RX div)

(*) environment dependent

Rx : Equ. sensitivity = -117.4 to - 121 dBm (*) (4RX div)

(*) environment dependent

n 1 TWIN module = 1 functional TRX = 8 radio TSn 2 RX & 4 RX diversity possiblen TX diversity used (à very high coverage)n Gain in sites numbers (less sites needed)n This mode is also called TX div moden Up to 12 TWIN TRM in MBI5/MBO2 cabinets

Tx : GSM 900 : 113 to 175 W (*) GMSKGSM 1800 : 88 to 136 W (*) GMSK

Tx : GSM 900 : 113 to 175 W (*) GMSKGSM 1800 : 88 to 136 W (*) GMSK

Higher Output Power

Higher Sensitivity

Coverage ModePrinciple





Coverage ModeTransmit Diversity (TxDiv)

t Tx Diversityn Same signal is transmitted over 2 antennas

with a given time difference

n Gain in downlink:– Dense Urban: 5.9dB,– Sub Urban: 4.6dB,– Rural: 4dB

n Equivalent to:– 900MHz: 113W to 175W– 1800MHz: 88W to 136W

TX1 TX2

Antenna Network

Twin TRX

Downlink: Tx Div

Antenna Network





Coverage Mode 4-way Receive Diversity

t 4 Rx diversityn Received signal from 4 different antennas

is combined in the TWIN module

n Gain in uplink vs. 2RxDiv:– Dense Urban: 4dB,– Sub Urban: 3.6dB,– Rural: 2.9dB

2 Antenna Networks are required in each sectorANB or ANC or GANB or GANC

Uplink: 4Rx Div

RX1 RX2 RX3 RX4

Twin TRX

Antenna Network

Antenna Network





Enhanced FlexibilityUnbalanced configurations

t Example of Unbalanced Configurationn 2 TRX MP (45W) + 1 Twin TRX TxDiv and 4RxDiv

n Sub-urban environment

MP

Unbalanced Config.

TxDiv

MP TxDiv+4RxDiv

4.08 Km5.16 Km

AGC AGC

TRX

MP

TRX

MPTxDiv:•129W•-119.6dBm

MP:•45W•-116dBm

TRX

TRX





2.4 Operator Commands Commands Impact

2 SELF-TESTS

4 SOFTWARE START-UP

5 NON-DESTRUCTIVE TESTS

6 CONFIGURATION DOWNLOADING /DATA BASE SYNCHRONISATION

7 FUNCTION START-UP

INIT

RESTART

RESET

DISABLE

3 SOFTWARE DOWNLOADING

1 BOOTSTRAP

IT

MSD





MxBSC Detailed impacts SBL hierarchy

ECU

TCU

SSW-HW*

BTS-Tel

BTS-OM

*

* BSS-Tel

CP-LOG*

ACH

ATR

N7* RSL OML*

DTC *

*

* CPR TSC*

CP-HW*

ETU

*

GSL

TR-OM

TP-HW*

SMM

BSC

*

SBL are hierarchically associated in a farther/child relationship (see §6.1)

*FAN* PEM* *BSC-ENV

BTS-POOL**

SMM: Shelf ManagerFAN: FAN tray

PEM: LIU or ATCA PEMBSC-ENV: Personality Card

SMM: Shelf ManagerFAN: FAN tray

PEM: LIU or ATCA PEMBSC-ENV: Personality Card

ETU: LIU boardSSW-HW: Switch ATCA

ECU: MUX board

ETU: LIU boardSSW-HW: Switch ATCA

ECU: MUX boardNo more X25, DISC, RS232,

BC-SYS-BUS and BC-RACK-BUSNo more X25, DISC, RS232,

BC-SYS-BUS and BC-RACK-BUS

CP-HW: OMCP and CCP boardTP-HW: TPGSM board

CP-HW: OMCP and CCP boardTP-HW: TPGSM board

CP-LOG: Set of VCE that aremapped on a CP-HW

CP-LOG: Set of VCE that aremapped on a CP-HW

No more BATTERY, CONV, SWITCH, CLK-GEN

and CLK-REP

No more BATTERY, CONV, SWITCH, CLK-GEN

and CLK-REP



BSS Hardware

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