Multi-Channel Assignment And Link Scheduling For Prioritized Latency-Sensitive Applications

Current wireless networks mainly focus on delay-tolerant applications while demands for latency-sensitive applications are rising with VR/AR technologies and machine-to-machine IoT applications. In this paper we consider multi-channel, multi-radio scheduling at the MAC layer to optimize for the performance of prioritized, delay-sensitive demands. Our objective is to design an interference-free schedule that minimizes the maximum weighted refresh time among all edges, where the refresh time of an edge is the maximum number of time slots between two successive slots of that edge and the weights reflect given priorities. In the single-antenna unweighted case with k channels and n transceivers, the scheduling problem reduces to the classical edge coloring problem when k >= [n/2] and to strong edge coloring when k = 1, but it is neither edge coloring nor strong edge coloring for general k. Further, the priority requirement introduces extra challenges. In this paper we provide a randomized algorithm with an approximation factor of (O) over tilde (max {root Delta(p), Delta(p)/root k}log m) in expectation, where Delta(p) denotes the maximum degree of the unweighted multi-graph, which is formed by duplicating each edge e(i) for w(i) times (w(i) is epsilon(i)'s integral priority value), and m is the number of required link communications (f(n) is an element of(O) over tilde (h(n)) means that f(n) is an element of O h(n) log(k) (h(n)) for some positive constant k. The results are generalized to the multi-antenna settings. We evaluate the performance of our methods in different settings using simulations).