The GSM system supports a maximum of 9%9=81 paging groups. the
MS can be divided into 81 sub-groups at most from the opinion of the paging
group. No matter what combination mode is adopted, the number of blocks used
for paging in every 51 multi-frame does not exceed 9. The system enables the 51
multi-frame to cycle again , with a quantity of “BS-PA-MFRAMS” (number of
frames of the same paging) of 51 multi-frames as a period.
Suppose that the number of frames
of the same paging is 7 and the number of paging blocks (9or3-BS_AG_BLKS_RES:
number of access granted reserved blocks) of each 51 multi-frame is 4. Then the
paging group number cycles between 0-27 (28 in total).
In GSM terms, the paging block in any 51
multiframe is called a paging super-group.
Therefore, the number of paging super-frames in the system is the “number of
frames of the same paging”. The number of paging groups in each super-group is
9 or 3 – “number of access granted reserved blocks”.
The number of paging blocks in each
51 multiframe is calculated
according to the following formula:
If the CCCH and SDCCH are combined
in one physical channel:
Number of paging groups per
super-group=3－number of access
granted reserved blocks
in other cases, i.e. the CCCH is
not combined with the SDCCH:
Number of paging groups per
super-group =9－
number
of access granted reserved blocks
Both the above two parameters:
“BS_AG_BLKS_RES” and the “BS-PA-MFRAMS” are broadcasted in system information
type 3
