A Distributed Joint Channel-Assignment, Scheduling and Routing Algorithm for Multi-Channel Ad-hoc Wireless Networks

Abstract

The capacity of ad hoc wireless networks can be substantially increased by equipping each network node with multiple radio interfaces that can operate on multiple non-overlapping channels. However, new scheduling, channelassignment, and routing algorithms are required to fully utilize the increased bandwidth in multi-channel multi-radio ad hoc networks. In this paper, we develop a fully distributed algorithm that jointly solves the channel-assignment, scheduling and routing problem. Our algorithm is an online algorithm, i.e., it does not require prior information on the offered load to the network, and can adapt automatically to the changes in the network topology and offered load. We show that our algorithm is provably efficient. That is, even compared with the optimal centralized and offline algorithm, our proposed distributed algorithm can achieve a provable fraction of the maximum system capacity. Further, the achievable fraction that we can guarantee is larger than that of some other comparable algorithms in the literature.

Distributed scheduling scheme for video streaming over multi-channel multi-radio multi-hop wireless networks

“…In addition, 3GPP LTE (Long Term Evolution) system using relay is also an example. As we know, LTE uses OFDM (Orthogonal Frequency Division Multiplexing) for the downlink, in which the transmitter sends information over a large number of sub-carriers [2]. So it can be viewed as a special type of multi-channel multi-radio multi-hop wireless system.…”

“…We assume that each radio can only tune to one channel at any given time and switch channels dynamically as in [2], [6]. Therefore, for link l to successfully communicate on channel c, both the sending and receiving nodes must tune one radio to channel c. In this case, the total LBR in I l can be defined as:…”

“…For background stream, it is generated according to an on/off source model with exponential distribution of staying time, and average rates between 0 and 0.2 · r in l for each link. To demonstrate the effectiveness of our proposed scheme, DMDS is benchmarked against other two popular scheduling schemes for multi-channel multi-radio wireless networks : i) Maximum Throughput Scheduling (MTS) introduced in [5], in which this scheme seeks for a feasible end-to-end rate allocation vector along with feasible channel assignment to achieve optimal throughput; ii) Provably-Efficient Maximal Scheduling (PEMS) introduced in [2], in which a distributed on-line algorithm is provided to achieve a provable fraction of the maximum system capacity. Fig.…”

“…Therefore, if each network node has multiple radio interfaces, it can then utilize a larger amount of bandwidth, and hence achieve a higher system capacity [2], [3].…”

“…For ease of exposition, in the rest of the paper to avoid the confusion, we will use of the term "scheduling" to refer to the combined operation of channel assignment, rate allocation and routing. Although some scheduling protocols can be obtained via extending the current algorithms in [1], [2], [5] that are known to achieve the maximum system capacity or throughput for multi-channel multi-radio networks. However, these works completely ignore the transmission content.…”