The Exponential Rule for Wireless Scheduling: Pathwise Optimality and State Space Collapse
نویسنده
چکیده
The task of supporting data flows over wireless channels is currently of great interest. This involves scheduling transmissions of multiple data flows over a shared wireless channel. The unique feature of this problem is the fact that the capacity (service rate) of the channel varies with time randomly and asynchronously for different users. The variations of the channel capacity are due to different (and random) interference levels observed by different users, and also due to fast fading [4], of a radio signal received by a moving user.
منابع مشابه
Optimality Properties of the M-EXP Scheduling Rule
We present the Multi-user EXP rule (M-EXP) for multiple-queue multipleserver scheduling motivated by a model for transmission to multiple users over a wireless broadcast channel. M-EXP is shown to be throughput optimal (i.e. achieves the largest possible stable input rate region) and pathwise optimal (i.e. minimizes system workload and maximum queue length) in the heavy traffic limit. This work...
متن کاملPathwise Optimality of the Exponential Scheduling Rule for Wireless Channels
We consider the problem of scheduling transmissions of multiple data users (flows) sharing the same wireless channel (server). The unique feature of this problem is the fact that the capacity (service rate) of the channel varies randomly with time and asynchronously for different users. We study a scheduling policy called Exponential scheduling rule, which was introduced in an earlier paper. Gi...
متن کاملLarge deviation sum-queue optimality of a radial sum-rate monotone opportunistic scheduler
A centralized wireless system is considered that is serving a fixed set of users with time varying channel capacities. An opportunistic scheduling rule in this context selects a user (or users) to serve based on the current channel state and user queues. Unless the user traffic is symmetric and/or the underlying capacity region a polymatroid, little is known concerning how performance optimal s...
متن کاملAsymptotically tight steady-state queue length bounds implied by drift conditions
The Foster-Lyapunov theorem and its variants serve as the primary tools for studying the stability of queueing systems. In addition, it is well known that setting the drift of the Lyapunov function equal to zero in steady-state provides bounds on the expected queue lengths. However, such bounds are often very loose due to the fact that they fail to capture resource pooling effects. The main con...
متن کاملScheduling for Multiple Flows Sharing a Time-Varying Channel: The Exponential Rule
We consider the following queueing system which arises as a model of a wireless link shared by multiple users. Multiple ows must be served by a \channel" (server). The channel capacity (service rate) changes in time randomly and asynchronously with respect to di erent ows. In each time slot, a scheduling discipline (rule) picks a ow for service based on the current state of the channel and the ...
متن کامل