Highly sectorized system for Internet wireless access
Elvino Silveira Sousa · 2002
The conceptual design of a system for Internet wireless access based on a large number of antenna sectors or fixed beams, with an overlapping structure, is proposed. The system utilizes spread spectrum modulation with time division multiplexing for transmissions from different overlapping antenna sectors. The fixed antenna beam structure is a practical approach to achieve space division multiplexing capacity gains with modest complexity. The time division multiplexing structure is shown to be a solution to the more general problem of designing sets of orthogonal signals for overlapping antenna sectors. We introduce the concept of time re-use as an analogue of frequency re-use in order to allocate time slots to clusters of antenna sectors. A frequency/time allocation strategy that depends on the terminal position within the cell and reduces interference is also introduced.