Abstract: A method and apparatus for a high-capacity cellular network by improved sectorization and interleaved channel assignment is presented. Data transmission over a cellular network is carried out by implementation of a sectorization scheme, called the Narrow-Beam Quad-sector Cell (NBQC) sectorization scheme, and the corresponding Interleaved Channel Assignments (ICA). The NBQC sectorization scheme calls for each cell of a cellular network to be divided into four sectors, with each sector covered by a 60 degree antenna. Use of the NBQC sectorization scheme allows for implementation of the corresponding ICA, in which assignment of transmission channels to each cell is based on a re-use factor of N=2. Accordingly, the interleaved channel assignments allow for the use of the transmission channels in cells which are adjacent in the cellular network.