摩托罗拉 2G-3G 互操作交流

1、摩托罗拉 2G-3G 互操作交流,02 / 02 / 2009,2G-3G组网策略,数据业务2G-3G参数配置策略： 尽可能使用TDS-CDMA进行数据业务： 调整2G系统的小区重选参数。 调整3G系统的小区重选参数。 调整3G系统的切换门限。 加大3G手机向2G的渗透，利用3G所提供的大带宽优势，最大化3G的应用。,数据话音2G-3G参数配置策略： 尽可能将话音业务保留在2G网络： 调整2G系统的小区重选参数。 调整3G系统的小区重选参数。 启动Direct Retry功能，是话音业务直接建立在2G系统上。 避免网络建设初期3G网络空洞所造成话音业务可能出现的性能下降。 避免TDSCDMA本

2、身上存在的一些物理层缺陷所造成的性能下降。,2G-3G初期组网结构,2G-3G覆盖的考虑 3G覆盖区是 隔离的小片覆盖区,2G,3G覆盖区,2G覆盖区,3G覆盖区,2G覆盖区,2G-3G初期组网结构,2/2.5G,3G-2G重叠覆盖下系统间重选和切换 3G 2G Handover 支持不同TD厂家的切换请求 2G 3G Handover GSR9: 支持基于测量， 负载均衡和业务的切换。,3G,General configuration,2G3G coverage area,TD初期 2G无线网络参数配置 -TDD_offset,为支持2G和TD之间的互操作，需要在2G无线网络上开启2G和TD

3、之间的互操作功能，并在有TD覆盖区域的2G无线网络上配置TD的邻区信息。若能确保2G小区的覆盖范围内TD覆盖良好，则不进行TD邻区配置。 Mot:最好还是配置双向邻区，并把TDD_Qoffset配置成0较好。 TDD_offset: 该参数的含义是当TD邻区的P-CCPCH RSCP与2G服务小区的RSSI的差值连续5秒大于TDD_offset时，将执行2G到TD的系统间重选。该参数在实际网优中需重点优化和调整，不同场景可以有不同的取值。该值的取值范围为-28dB,+28dB、负无穷。该取值可参考实际网络的TD和2G信号的差值、Qsearch_I值来设置。 假定实际网络的TD和2G信号的差值为

4、V，QSearch_I取值为8时对应的门限电平为Th，则TDD_offset取值最好能同时满足以下两个条件： 条件1：TDD_offset=-95dBm-90dBm(-95-85dBm为TD小区语音业务门限电平)，以保证重选后的TD网络具备较好的信号质量，可满足基本的业务要求。 比如：同一地点TD信号比2G信号弱13dB，则根据条件1，TDD-offset应设置为=-17dB-13dB；上述两个的区间的交集为-13dB, 则TDD-offset最终设置值建议为-13dB。,2G无线网络参数配置-Qsearch_I,QSearch_I：该参数的含义是当2G小区的RSSI在达到一定门限时开始启动对

5、TD小区的测量。为保证优选TD网络，该参数在建网初期建议取值为8（该值表明当2G服务小区的信号强度高于-78dBm时，终端将启动对TD邻区的测量） Mot:如果信号强度低于-78dBm时候反而不再测量TD邻区的话，手机就没有机会重选入3G系统，因此还是推荐牺牲掉手机的耗电来换取能够获取及时高速的3G服务。也就是推荐设成7,System information update,SI2 TDD_Qoffset和Qsearch_I SI2quater SI3: SI2quater Indicator SI13: BCCH_CHANGE_MARK (3 bit field) This field ind

6、icates the status of the information on BCCH. The value of this field may be changed when information on BCCH is changed, see 3GPP TS 44.060. SI_CHANGE_FIELD (4 bit field) 结合BCCH_Change_Mark 表明具体那个系统消息变化了,New BSS element,TD_enabled,Attribute Values:,Valid Values: 0 = off, 1 = on. Default: The defaul

7、t value is off (0).,Dependencies: Modification of td_enabled is only allowed when TD-SCDMA inter-working feature (tdOpt) is unrestricted. Modification of td_enabled from disable to enable is only allowed when RDB 4225 Inter-RAT Handover feature (InterRatOpt) and FR22879 Enhanced 2G/3G Inter-RAT hand

8、over feature (EnhancedInterRatOpt) are both restricted.,Environment: This parameter may be changed inside and outside of SYSGEN mode. There is no warning when its changed inside SYSGEN. Outside of sysgen, the warning is only printed when td_enabled is changed to 0.,New BSS element,tdd_offset Descrip

9、tion: The new per CELL element - tdd_qoffset is used in the cell reselection algorithm followed by the MS for UMTS TDD neighbor cell. Attribute Values:,Dependencies: Modification of this element will not be allowed when the TD-SCDMA inter-working feature is restricted. Environment: This element can

10、be modified in or out of SYSGEN mode,New BSS element,qsearch_i, qsearch_c_initial Description: If TD-SCDMA inter-working is unrestricted, BSC shall support the modification and display of following elements for TD-SCDMA neighbor cell.,New BSS element,add_neighbor Description: The MMI neighbor comman

11、ds will be updated to support the TD-SCDMA neighbor cell in the BSS database and to support the TD-SCDMA inter-working feature. These commands will allow the BSS to add, delete, modify, and display TD-SCDMA cells in the database. These commands will continue to support the existing GSM cell format.

12、Accessibility: If the local_maintenance flag is disabled the MMI is prevented from creating, modifying or deleting the TD-SCDMA neighbor. Instances: Up to 16 TD-SCDMA neighbors per cell.,Dependencies: A cell can only support a maximum of 16 TD-SCDMA neighbors. A cell can only support a maximum of 3

13、TDD-ARFCN for its TD-SCDMA neighbors. Note: The maximum of 16 TD-SCDMA neighbors per TDD-ARFCN is implied.,New BSS element,Attribute Values:,New BSS element,Prompted Parameters for TD-SCDMA Neighbors: Note: Placement is umts_tdd Any prompts with required field set to No will use the default value if

14、 no value is entered.,Command line para.:,New BSS element,modify_neighbor Description: Modify a neighbor cell parameter in the BSS database. This command shall be updated to allow the modification of both GSM and UTRAN neighbor cells within the BSS database,Dependencies: A TD-SCDMA neighbor specific

15、 parameter cannot be modified for a GSM neighbor cell. A GSM neighbor specific parameter cannot be modified for a TD-SCDMA neighbor cell. The specified TD-SCDMA cell identifier must exist as a neighbor cell of the GSM source cell.,New BSS element,disp_neighbor Description: Display information on a s

16、pecific neighbor cell or all neighbor cells in the BSS database. This command shall be updated to display additional information for TD-SCDMA neighbor cells. Cmd Line Parameters: No change Dependencies: No change. del_neighbor Description: Delete a TD-SCDMA neighbor cell from the BSS database. Cmd L

17、ine Parameters: No change.,Feature implementation,1. Verify TD-SCDMA Inter-working feature is unrestricted, and both InterRAT Handover feature (RDB4225) and FR22879 Enhanced 2G/3G Inter-RAT handover feature are restricted. disp_options all The following optional feature is unrestricted: 86 TD-SCDMA

18、Inter-working Feature The following optional features are restricted: 50 InterRAT Handover 67 Enhanced 2G/3G Inter-RAT handover 2. At the OMC select appropriate BSS, open BSS Detail View, verify that tdOpt is enabled (1). 3. Display the value of td_enabled. disp_element td_enabled 0 td_enabled=0 COM

19、MAND ACCEPTED 4. Change the value of td_enabled to 1, verify that command is accepted. chg_element td_enabled 1 0 COMMAND ACCEPTED,Feature implementation,5. Add TD_SCDMA neighbour cell TD_cell_1 as a neighbor of GSM cell GSM_cell_1 with all values entered for all parameters. add_neighbor umts_tdd enter the UTRAN Absolute Radio Freq Chan Number: 10054 enter the TD-SCDMA cell parameter: 49 enter the Time Switched Transmit Diversity Flag: 1 enter the Space Code Transmit Diversity Flag: 1 COMMAND ACCEPTED 6. Display the T