1. 後卓越計畫進度報告 楊舜仁老師實驗室 2007.08.13

2. 2 Overlapping RA Scheme Reduce the RAU cost caused by the ping-pong effect In overlapping RA scheme, one cell may belong to two or more RAs RA1 # of RAU = 2 # of RAU = 1 RA2 RA1 RA2 Non-overlapping Overlapping  Each cell has a corresponding RAC list The first one in the RAC list is called the default RAC (DRAC) The others are called the overlapping RACs (ORACs)  RAC distribution: Every RAC list consists of an RAC distribution for MSs Express the proportion for MSs registering to RA i distributed value

3. 3 Propose Scheme We propose a dynamic RA adjustment algorithm for with overlapping RA configuration  According to user mobility and call The cells are included in initial RA i  Be referred to as the core cells of RA i  Never be removed from RA I The RA adjustment algorithm only includes or excludes those cells at RA boundaries  External boundary,  Internal boundary, Internal boundary External boundary Core cells

4. 4 Network Loads Assumption  : the number of MSs moving from cell (x,y) to cell (x’,y’)  : the RAU probability of the MSs from cell (x,y) to cell (x’,y’) e.g.  : the number of incoming call arrivals to cell j  : the number of cells in RA i  : the distributed value for RAC(i) RAU load :  # of MSs performing the RAU RAU load from cell (x,y) to cell (x’,y’)  Paging load  # of MSs in RA i Paging load of cell j to RA i  the number of incoming call arrivals

5. 5 Adjustment Algorithm

6. 6 Remove a cell from RA i  Selects the cell that has the highest paging load to RA i Cell Exclusion Paging improvement

7. 7 RA1 RA4 RA1 RA4 Cell Inclusion Add a cell into RA i  Selects the cell that has the highest RAU load to RA i RA1 RA4 RAU improvemen t

8. 8 Stable State Return to step 2 until the adjustment is a stable stable  No cells can be added or removed Check (RM_cell=0 and ADD_cell=0 ? )  Stable RM_cell=0 and ADD_cell=0 Select next RA to adjust  Non-stable RM_cell≠0 or ADD_cell ≠ 0 Continue the next run of cell exclusion and inclusion

9. 9 Prediction of the RAC Distribution 1. Determines respective RAC distributions of cells 2. Predicts respective RAC distributions of cells according to the number of MSs and respective RAC distributions of neighboring cells 3. Repeats step1 to step 2 until becoming stable

10. 10 Example Compute the number of neighboring MSs moving to cell (1,3) and registering to RA 1 and RA 4 in cell (1,3)  Then, 

11. 11 Effects of ∆ u (Θ p =10000,Θ u =500 and ∆ p =0.2) Effects of ∆ p (Θ p =10000,Θ u =500 and ∆ u =0.02)