Paging Optimization Practical Experience
3How Paging works?2
4Paging capacity in the BTS2
4.2Paging block structure2
4.4Queuing in the BTS2
5Paging Strategies via A-interface2
5.2Calculating paging capacity2
5.3Estimated maximum LA size2
5.4Paging capacity in the BSC2
5.5LA dimensioning strategies2
6Paging strategy used over ATM-Mobilis network2 6.1Introduction2
6.2Paging strategy over ATM-Mobilis network2
6.3New paging strategy over ATM-Mobilis network2
7.2Statistic counters & KPI formulas2
8Results and interpretations2
8.2Location Update Results2
8.3Random Access Results2
The aim of this document is to present the new paging Strategy applied over ATM-Mobilis network.
It’s also gives brief description of the improvement for some of the main KPIs after changing the Paging strategy from IMSI to TMSI over the network.
Since bandwidth is a very insufficient resource in radio networks, it is necessary to subdivide the service area into many cells in order to allow the reuse of frequencies. If a call has to be established for a mobile user in a cellular network, for efficient location management it is desirable to know the current cell of the subscriber and transmit the call setup message (called paging operation and paging message) only in this cell. Unfortunately, the "knowledge" about the current position of the mobile user is not for free. Due to the mobility of the user, it is obvious that the mobile station will enter and leave cells and this information must be updated in the network management to establish mobile terminated calls.
A Location Area (LA) is a group of cells in which a page will be broadcasted. The upper boundary for the size of an LA is the service area of a Mobile services Switching Centre (MSC). In general the LAs are smaller than that, mainly due to the excessive paging load that a large LA would have to handle. The lower boundary for the size of a LA is set by the Location Updating load, causing increased demand for Stand alone Dedicated Control CHannel (SDCCH) resources in the LA border cells.
By analyzing statistics it is possible to get information on how many pages, first and second, which are issued. However this does not actually indicate whether the paging load should be considered low, medium or (too) high. A gauge such as the maximum possible paging rate for each unit involved (e.g. BSC, BTS) is needed in the evaluation of the paging load.
The positions of the users are stored in central databases in terms of LAs and the paging message will be broadcasted in all cells of the LA.
How Paging works?
When a Mobile Station (MS) is paged, a Paging message is sent from the MSC to each Base Station Controller (BSC) belonging to that MSC's service area (global page), or to those BSCs serving at least one cell belonging to the LA where the MS is registered (local page).
For each Paging message received by the BSC, Paging Command messages...