Optimal Downlink Data Transmission Scheduling in Next Generation Wireless Systems.

The scheduling of data transmission from base station to mobiles, in wireless CDMA based systems, is formulated as an optimal control problem under a quadratic objective. Minimum tune transmission requires a scheduling scheme whereby attention is devoted to a single mobile at a time, and maximum available power is used when transmitting. However, amongst the infinitely many candidate time minimizing schedules, some are deemed fairer or better in some sense than others. We show how quadratic type objectives are flexible enough to skew the controls in the desired direction, and furthermore, we establish that the solution to the resulting optimal control problem (quadratic objective, linear in the dynamics with nonlinear state constraints) can be approached via a standard linear quadratic regulator framework. Scalability of the proposed algorithms is achieved for large numbers of users through an exact aggregation theory