In the early deployment of cellular systems or even today in areas of low usage, omni-directional antennas are used.

In the early deployment of cellular systems or even today in areas of low usage, omni-directional antennas are used. In areas where the usage is higher, the cellular systems are designed to provide narrow sectors of coverage from each antenna, perhaps using a 120o or 90o sector. Besides eliminating interference between base stations, using sector antennas may also influence the power level a base station must transmit. What effect would you expect switching from a omni-directional to a 90o sector antenna would have. How? How would you characterize the effect?