15: 15:1 Data Configuration DescriptionIntroductionWhat the service carrier is after is maximum profits. So it requires the equipment supplier to use minimum resources to perform maximum functions, and to bring resources to their full play. Here, the efficient use of trunk resources is necessary, as trunk equipment on the market is very expensive. Nowadays, trunk equipment provided by foreign manufacturers on the market can already realize the trunk multiplexing of or over 15:1. As the form suggests, 15:1 means that trunks that 15 TRXs should pass are on one E1. In this way, resources can be fully used.

One E1 cable has 31 64K time slots, but one voice channel of the ABIS interface is 16K, and the signaling channel is not 64K. So, the multiplexing mode can be adopted to make full use of E1 cables. 15:1 means that one E1 led out from BSC can carry 15 TRXs of BTS. Now consider the usual case. (as channels such as BCCH exist), it is regarded that each TRX in a cell approximately corresponds to 7.2 voice channels, demanding (7.2*15/4) 27 time slots. The 32 time slots on the E1 can be distributed as follows: 1 synchronous clock time slot, 27 voice time slots (transmitting 108 voices), with the remaining 4 time slots transmitting RSL and OML messages. The time slot distribution diagram in 15:1 mode is as follows: 0 1 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 V1 V5 V9 V13 V17 V21 V25 V29 V33 V37 V41 V45 V49 V53 V57 V61 V65 V69 V73 2 3 4 5 synchronous V2 V3 V6 V7 V10 V11 V14 V15 V18 V19 V22 V23 V26 V27 V30 V31 V34 V35 V38 V39 V42 V43 V46 V47 V50 V51 V54 V55 V58 V59 V62 V63 V66 V67 V70 V71 V74 V75 6 7 V4 V8 V12 V16 V20 V24 V28 V32 V36 V40 V44 V48 V52 V56 V60 V64 V68 V72 V76

20 21 22 23 24 25 26 27 28 29 30 31

V77 V78 V79 V80 V81 V82 V83 V84 V85 V86 V87 V88 V89 V90 V91 V92 V93 V94 V95 V96 V97 V98 V99 V100 V101 V102 V103 V104 V105 V106 V107 V108 RSL11,12,13,14 RSL7,8,9,10 RSL3,4,5,6 OML+RSL0,1,2

Time slot 1 to time slot 27 on the E1 cable has 108 16K sub-time slots, to be used by service channels of 15 TRXs. Vi refers to the No.i service channel at this site. There are 16 signaling links, and every 4 signaling links share one 64K time slot.

15:1 Main tables involved in data configuration1. Radio channel configuration table and service channel configuration table

The radio channel configuration table configures the distribution of various channels on the BS interface. According to the distribution of this channel at the ABIS interface and the BIE logic correspondence relationship, we can obtain the trunk circuit No. used by this channel. If this channel is a non-service channel (BCCH, SDCCH), then the trunk circuit No. is 65535. Note that in the 15:1 configuration, the time slots No.96-111 at the BS port on the 32BIE cardare for signaling only. So, the trunk circuit No. in the radio channel configuration table must avoid these time slots. The time slot No. in the service channel configuration table is the E1 time slots, ranged from 1-27, with sub-time slots configured from 0-3. If this channel is a non-service channel (BCCH, SDCCH),

then configure the time slot No. as 65535, and the sub-time slot No. as 255.For example, the two tables can have the following configurations:

SITE No. 0 0 0 0 0 0 0

TRX No. 0 0 0 0 0 0 0

Channel No. 0 1 2 3 4 5 6

Channel type Master BCCH SDCCH8 TCH/F TCH/F TCH/F TCH/F TCH/F

Trunk circuit No. 65,535 65,535 256 257 258 259 260

Time slot 65,535 65,535 1 1 1 1 2

Sub-time slot 255 255 0 1 2 3 0

0 0 0 0 0 0 0 0 0

0 1 1 1 1 1 1 1 1

7 0 1 2 3 4 5 6 7

TCH/F SDCCH8 TCH/F TCH/F TCH/F TCH/F TCH/F TCH/F TCH/F . . .

261 65,535 262 263 264 265 266 267 268

2 65,535 2 2 3 3 3 3 4

1 255 2 3 0 1 2 3 0

2. LAPD signaling connection table, LAPD semi-permanent connection table, and signaling channel connection table The signaling channel connection table configures the time slot distribution of various signaling channels on the E1 cable. The 15 RSL links should be distributed on the 4 time slots (OML link is fixed at the time slot No.31). The various time slots can be made to share the load according to the flow of each link. And RSL links of TRXs with SDCCH channels can be distributed on different time slots. The LAPD semi-permanent connection table and the LAPD signaling connection table configure physical link No., TEI and trunk circuit No. according to the signaling connection No., the used LAPD card port, and the BIE logic correspondence relationship. The trunk circuits of signaling in the semi-permanent connection table can be distributed only to the 96-111 time slots on the 32BIE card. Note that the TEI of different signaling links must be set with a different value. And the TEI value of OML links must be set to be the minimum value in the TEI values of various signaling links (recommended to be 0). Also note that one CPU on the LAPD card can be configured with a maximum of only 16 links. If the link configuration is greater than 16 or if the links with a higher priority on other cards share load with the local card, it might lead to failure of the setup of part of links. For example, the signaling link connections have the following configurations:

SITE No.

TRX No.

Signali ng connect ion No. 0 1 2 3 4 5 6 7

0 0 0 0 0 0 0 0

0 1 2 3 4 5 6 7

Signali ng connect ion type RSL RSL RSL RSL RSL RSL RSL RSL

Physica l link No.

TEI

Trunk circuit No.

Time slot

Sub time slot

96 96 96 97 97 97 97 98

1 2 3 4 5 6 7 8

111 111 111 110 110 110 110 109

31 31 31 30 30 30 30 29

1 2 3 0 1 2 3 0

0 0 0 0 0 0 0 0

8 9 10 11 12 13 14

8 9 10 11 12 13 14 15

RSL RSL RSL RSL RSL RSL RSL OML

98 98 98 99 99 99 99 96

9 10 11 12 13 14 15 0

109 109 109 108 108 108 108 111

29 29 29 28 28 28 28 31

1 2 3 0 1 2 3

2. BIE card description table

In the BSC BIE card description table, field "LAPD rate" selects "64K statistics multiplexing"; the ABIS interface has the TRX time slots No.1 the FUL time slots No.2827, the ABIS interface has 95, the BS1

31, the BS1 interface has the TRX time slot No. 0 111, and OML has the time slot of 111.

interface has the FUL time slot No. 96 Module No. Active/standby group No. Port No. Connection mode TRX starting time slot No. at the ABIS interface TRX ending time slot No. at the ABIS interface FUL starting time slot No. at the ABIS interface FUL ending time slot No. at the ABIS interface OML starting time slot No. at the ABIS interface OML ending time slot No. at the ABIS interface LAPD rate TRX starting time slot No. at the BIS interface TRX ending time slot No. at the BIS interface FUL starting time slot No. at the BIS interface FUL ending time slot No. at the BIS interface OML starting time slot No. at the BIS interface OML ending time slot No. at the BIS interface

1 0 0 Chain type 1 27 28 31 31 31 64K statistics multiplexing 0 95 96 111 111 111

The values of various options in the "LAPD rate" field are as follows:

Option name "32K" "64K" "64K statistics multiplexing"3. Handover control data table

Value 32 64 2

In the handover control data table, "receiving level fast drop emergent handover algorithm allowed determines whether to make the emergent handover judgment during the BTS measuring report preprocessing. This is usually set as TRUE. BTS measuring report preprocessing indicates whether BTS makes measuring report preprocessing. In the 15:1 configuration, this is normally set as TRUE, otherwise, the link rate is not enough. The "preprocessing measuring report frequency item refers to the submitting frequency of the processing measuring report. This item is valid only during the measuring report BTS preprocessing.

Reference document (15:1 Software Outline Design Description Manual) by

Li Jie GSMBMrr&3201021