R- GSM extended
II. Dynamic Additional Sub-TS
Under CS-1/CS-2,BSS is also based on the 16kbit/s link at the G-Abis interface. When CS-3 and CS-4 is adopted, the rate of a PDCH is 15.6 kbit/s and 21.4 kbit/s, therefore,
PDCH permanently onto two 16kbit/s links will greatly decrease the multiplexing ratio of the G-Abis interface, and thus greatly reduce the utilization ratio of the G-Abis interface transmission equipment.
With dynamic additional sub-TS allocation, M900/M1800GPRS BSS can resolve the transmission issue of CS-3 and CS-4 on the G-Abis interface perfectly. The dynamic attached sub-slot technology is to statically allocate a main 16 kbit/s sub-timeslot and dynamically allocate a attached 16 kbit/s sub-timeslot at the G-Abis interface for the CS-3/CS-4 PDCH. With the dynamic additional sub-TS technology, it is not necessary for GPRS BSS to upgrade the hardware of BTS, BSC or PCU for supporting CS-3 and CS-4. In addition, in its support for CS-3 and CS-4, the multiplexing ratio of the G-Abis interface is greatly improved, thus saving investments on the G-Abis interface transmission equipment.
The dynamic additional sub-TS technology used by M900/M1800GPRS BSS displays the following features:
z Any idle Sub-TS of the G-Abis interface can be used as additional sub-TS, so that each has maximum utilization.
z Within a same site address, the additional sub-TSs can be dynamically attached to various main TSs to enhance the utilization ratio of this sub-TSs according to statistical multiplexing rules.
z The locations of the additional 16kbit/s sub-TS are relatively flexible. They do not have to be adjacent to the main 16kbit/s sub-TS.
z It packs and unpacks the data packets through software to avoid hardware upgrading.
III. Parameter
M900/M1800 BSS supports four types of coding schemes: CS-1~CS-4. The configuration related to channel coding schemes is realized with the command pcu add cspara. The following parameters are involved.
1) UpFixCs
Description: CS fixedly adopted for uplink.
Value range: cs1, cs2, cs3, cs4, unfixed Default: cs2
2) UpDefaultCs
Description: Default CS adopted for uplink. If the uplink configured to adjust CS type dynamically, then the CS of the first TBF to transfer can be set by this parameter, the CS of other TBF is dynamically adjusted according to the signal transmission quality.
Value range: cs1, cs2, cs3, cs4.
3) UpThdCs1Cs2
Description: The resend rate conversion threshold, i.e. when the resend rate of the uplink TBF is smaller than or equals to this value, the coding scheme of it changes from CS-1 to CS-2.
Value range: 0~100 Default: 5
4) UpThdCs2Cs1
Description: Uplink TBF retransmission rate conversion threshold from CS-2 to CS-1, i.e. when the uplink TBF retransmission rate is larger than or equals to this value, the uplink TBF coding scheme changes from CS-2 to CS-1.
Value range: 0~100 Default: 10
5) UpThdCs2Cs3
Description: Uplink TBF retransmission rate conversion threshold from CS-2 to CS-3, i.e. when the uplink TBF retransmission rate is smaller than or equals to this value, the uplink TBF coding scheme changes from CS-2 to CS-3.
Value range: 0~100 Default: 10
6) UpThdCs3Cs2
Description: Uplink TBF retransmission rate conversion threshold from CS-3 to CS-2, i.e. when the uplink TBF retransmission rate is larger than or equals to this value, the uplink TBF coding scheme changes from CS-3 to CS-2.
Value range: 0~100 Default: 20
7) UpThdCs3Cs4
Description: Uplink TBF retransmission rate conversion threshold from CS-3 to CS-4, i.e. when the uplink TBF retransmission rate is smaller than or equals to this value, the uplink TBF coding scheme changes from CS-3 to CS-4.
Value range: 0~100 Default: 10
8) UpThdCs4Cs3
Description: Uplink TBF retransmission rate conversion threshold from CS-4 to CS-3,
Value range: 0~100 Default: 20
9) DnFixCs
Description: Fixedly adopted CS for downlink.
Value range: cs1, cs2, cs3, cs4, unfixed.
Default: unfixed 10) DnDefaultCs
Description: Default CS adopted for downlink. If the downlink dynamically adjusts CS, then the CS of the first TBF can be set by this parameter, the CS type of other TBF is dynamically adjusted according to the signal transmission quality.
Value range: cs1, cs2, cs3, cs4.
Default: cs2 11) DnThdCs1Cs2
Description: Downlink TBF retransmission rate conversion threshold from CS-1 to CS-2, i.e. when the downlink TBF retransmission rate is smaller than or equals to this value, the downlink TBF coding scheme changes from CS-1 to CS-2.
Value range: 0~100 Default: 5
12) DnThdCs2Cs1
Description: Downlink TBF retransmission rate conversion threshold from CS-2 to CS-1, i.e. when the downlink TBF retransmission rate is larger than or equals to this value, the downlink TBF coding scheme changes from CS-2 to CS-1.
Value range: 0~100 Default: 10
13) DnThdCs3Cs2
Description: Downlink TBF retransmission rate conversion threshold from CS-3 to CS-2, i.e. when the downlink TBF retransmission rate is larger than or equals to this value, the downlink TBF coding scheme changes from CS-3 to CS-2.
Value range: 0~100 Default: 20
14) DnThdCs3Cs4
Description: Downlink TBF retransmission rate conversion threshold from CS-3 to CS-4, i.e. when the downlink TBF retransmission rate is smaller than or equals to this
Value range: 0~100 Default: 10
15) DnThdCs4Cs3
Description: Downlink TBF retransmission rate conversion threshold from CS-4 to CS-3, i.e. when the downlink TBF retransmission rate is larger than or equals to this value, the downlink TBF coding scheme changes from CS-4 to CS-3.
Value range: 0~100 Default: 20
16) MaxFixCs34Pdch
Description: The fixed maximum number of PDCH supporting CS-3/CS-4 in this cell.
Value range: 0~255 Default: none
2.3.5 Supported Network Control Modes
During the cell reselection required by network, the network requires MS to send MR so as to control the cell reselection. Here three network control modes are defined.
z NC0: MS controlled cell re-selection, no measurement reporting.
z NC1: MS controlled cell re-selection, MS sends measurement reports.
z NC2: Network controlled cell re-selection, MS sends measurement reports.
Huawei BSS supports NC0.
I. Parameter
Network control mode parameter is configured with the command pcu add relatedinfo in PCU.
Parameter: NCO
Description: Network control mode.
Value range: nc0, nc1, nc2
Default: Currently fixedly set as "nc0", meaning MS controlled cell re-selection, no measurement reporting