Approximate interference of a microcellular spread spectrum system [comment]
An approximate technique for determining the adjacent cell interference of a microcellular code division multiple access (CDMA) system is described in the original paper [see ibid., vol. 31, no. 20, p. 1782-3, 1995]. An illustration of the hexagonal cellular model is given in that paper. The argument for the proposed technique is the following: since the variance of adjacent cell interference depends on the position of the mobile user in an adjacent cell, it is difficult to evaluate the exact value of variance for this hexagonal cellular model. To avoid dependence on position, the calculated variance of adjacent cell interference is averaged over the area of the cell where the mobile user is located. Furthermore, the hexagonal cell is approximated with a circular cell of equal area criterion. However, the approximation of a hexagonal cell by a circular cell with equal area is inaccurate.