Joint power and handoff control using a hybrid systems framework

Power control and handoff are two significant problems for cellular wireless systems. While both problems have received considerable attention of late, the problems are not often treated in a joint manner. Combined downlink power control and handoff design for cellular communication systems using a hybrid system framework is considered herein. Two new algorithms are proposed. The first one is a hard handoff/power control algorithm that endeavors a tradeoff between three performance criteria: transmitted power, number of handoffs and call quality. The second algorithm is a joint soft handoff/power control algorithm that takes into account the effect of the number of base stations in the active set in addition to the above performance criteria. The significance of the algorithms is that they incorporate the effects of channel fading and mobility, and achieve a tradeoff between the satisfaction levels of the mobile user and the network operator, thereby provide satisfactory service for the user while reducing the burden on the network such as undesired switching between base stations. The tradeoffs involved in both algorithms are verified through simulations.