Point to multipoint cell plan and migration
First Claim
Patent Images
1. Method of performing a migration from a first cell-plan to a second cell plan,the first cell plan comprises cells having four 90°
- sectors to each of which one of four orthogonal channels (a, b;
A, B) are allocated;
the first cell plan includes four specific cell types (6, 7, 8, 9) which are periodically repeated over the first cell plan, each cell type having a specific allocation of channels (a, b;
A, B) to specific sectors;
whereina particular channel is allocated to an even number of sectors per cell;
no same channel (a, b;
A, B) is allocated to corresponding sectors (*) - that is, sectors having a given orientation - of all four cell types;
no same channel (a, b;
A, B) is allocated to adjacent sectors (X) of any cell type;
no same channel (a, b;
A, B) is allocated to a particular sector of any given cell type and an adjacent sector (#) of any other cell type to the corresponding sector of the particular sector found in the directions of the sector boundaries of the particular sector;
the method comprising the step ofsplitting a given pair of corresponding 90°
sectors of the first and third (6, 8) cell type, respectively, or of the second and fourth (7, 9) cell type, respectively, into two pairs (13, 14;
15, 16) of corresponding split 45°
sectors; and
re-allocating channels by interchanging channels for one (13, 14) of said two pairs of corresponding split sectors while keeping the channel allocation for the other (15, 16) of said two pairs of split sectors according to the first cell plan,the first and third (6, 7) types of cells being selected such that any splitting and re-allocation can be performed such that after the re-allocation, adjacent sectors of a given cell have different channels.
1 Assignment
0 Petitions
Accused Products
Abstract
The present invention relates to cell plans and cell plan changes in point to multipoint systems (PMP). A cell plan arrangement is provided comprising cells having four 90° sectors to which individual sector at least one of four orthogonal channels, such as channels distinguished by two frequencies and two polarisations, are allocated. A method is furthermore provided allowing gradual sector-by-sector migration into a 45° sector cell plan. The cell plan offers advantageous carrier to interference ration (C/I) improvements.
8 Citations
11 Claims
-
1. Method of performing a migration from a first cell-plan to a second cell plan,
the first cell plan comprises cells having four 90° - sectors to each of which one of four orthogonal channels (a, b;
A, B) are allocated;the first cell plan includes four specific cell types (6, 7, 8, 9) which are periodically repeated over the first cell plan, each cell type having a specific allocation of channels (a, b;
A, B) to specific sectors;
whereina particular channel is allocated to an even number of sectors per cell; no same channel (a, b;
A, B) is allocated to corresponding sectors (*) - that is, sectors having a given orientation - of all four cell types;no same channel (a, b;
A, B) is allocated to adjacent sectors (X) of any cell type;no same channel (a, b;
A, B) is allocated to a particular sector of any given cell type and an adjacent sector (#) of any other cell type to the corresponding sector of the particular sector found in the directions of the sector boundaries of the particular sector;
the method comprising the step ofsplitting a given pair of corresponding 90°
sectors of the first and third (6, 8) cell type, respectively, or of the second and fourth (7, 9) cell type, respectively, into two pairs (13, 14;
15, 16) of corresponding split 45°
sectors; and
re-allocating channels by interchanging channels for one (13, 14) of said two pairs of corresponding split sectors while keeping the channel allocation for the other (15, 16) of said two pairs of split sectors according to the first cell plan,the first and third (6, 7) types of cells being selected such that any splitting and re-allocation can be performed such that after the re-allocation, adjacent sectors of a given cell have different channels. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11)
- sectors to each of which one of four orthogonal channels (a, b;
Specification