Joint Opportunistic Scheduling and Selective Channel Feedback

Abstract

Abstract-It is well known that Max-Weight type scheduling algorithms are throughput optimal since they achieve the maximum throughput while maintaining the network stability. However, the majority of existing works employing Max-Weight algorithm require the complete channel state information (CSI) at the scheduler without taking into account the associated overhead. In this work, we design a Scheduling and Selective Feedback algorithm (SSF) taking into account the overhead due to acquisition of CSI. SSF algorithm collects CSI from only those users with sufficiently good channel quality so that it always schedules the user with the highest queue backlog and channel rate product at every slot. We characterize the achievable rate region of SSF algorithm by showing that SSF supports 1 + fraction of the rate region when CSI from all users are collected. We also show that the value of depends on the expected number of users which do not send back their CSI to the base station. For homogenous and heterogeneous channel conditions, we determine the minimum number of users that must be present in the network so that the rate region is expanded, i.e., > 0. We also demonstrate numerically in a realistic simulation setting that this rate region can be achieved by collecting CSI from only less than 50% of all users in a CDMA based cellular network utilizing high data rate (HDR) protocol.

Traffic-Aware Training and Scheduling for MISO Wireless Downlink Systems

“…It was initiated in [34], [35] for sum-rate maximization without considering the queues of the users. The recent work [36] addressed the problem of stability region expansion. Therein, the channel state of the user with the largest queue is used as threshold.…”

Toward Optimal Rate-Delay Tradeoff for Computation Over Multiple Access Channel

“…In [34], the authors proposed a channel state feedback algorithm with multiple feedback thresholds to reduce the number of users transmitting feedback to a minimum. A joint opportunistic scheduling and limited feedback was proposed in [35], which only collected CSI from the users with sufficiently good channel quality. The discussion was further extended to the multi-antenna scenario in [36] and the multi-channel scenario in [37].…”

Throughput Maximization in Uncooperative Spectrum Sharing Networks

“…In the seminal work of [2] and [3], an adaptive queuelength-based algorithm, MaxWeight scheduling, was shown to achieve throughput-optimality; i.e., for any achievable traffic demand put on the network, MaxWeight successfully schedules the transmissions to meet the demand. Over the past decades, the MaxWeight algorithm and its extensions have had great success and have been applied to network switching [4], satellite communications [5], ad-hoc networking [6], [7], packet-delivery-time reduction [8], scheduling with selective and delayed feedback [9], [10], multicasting/broadcasting [11]- [13], multi-user MIMO [14], and age-of-information minimization [15], [16]. The MaxWeight algorithm makes scheduling decisions sequentially-over-time by first observing the backlog of queued packets at each node and then using these observations to adaptively schedule a simultaneous nonconflicting set of links to transmit.…”