Channel allocation schemes

About: Channel allocation schemes is a research topic. Over the lifetime, 10656 publications have been published within this topic receiving 182117 citations.

Congestion Control and Channel Assignment in Multi-Radio Wireless Mesh Networks

Abstract: We address the problem of congestion control in multi-radio, multi-channel, wireless mesh networks. Compared to its single radio counterpart for which solutions exist, this problem is significantly more complex because it requires the radio channel assignments and the traffic allocations per channel be jointly optimized. We address the problem by introducing a formulation that allows its decomposition in two subproblems: A congestion control subproblem for traffic allocation to a fixed channel assignment over a node path and a discrete combinatorial channel assignment subproblem. We solve the conditional congestion control subproblem by mapping it to an optimization problem of traffic distribution to a set of radio paths. The solution provides channel congestion information that is utilized to address the channel assignment subproblem. This leads to an iterative procedure which guarantees successive increases to overall network utilization. Compared to existing work on multi- radio, multi-channel mesh networks, we show that our approach can yield significant gains both in terms of network utilization and establishing fairness.

Dynamic single frequency networks

Abstract: Wireless asymmetric Internet access with a downlink peak bit rate of 10 to 30 Mb/s can be achieved by using the terrestrial digital video broadcasting system (DVB-T) as a supplemental downlink together with today's cellular systems. This paper is a study of dynamic radio resource management on a packet-by-packet basis for this broadband downlink. The dynamic single frequency networks (DSFN) scheme is evaluated. It exploits the macrodiversity capability of the OFDM modulation scheme. The transmitters are dynamically divided into groups of transmitters that send the same information at the same channel frequency simultaneously. The fairly shared spectrum efficiency (FSSE), in bits per second per Hertz per site, which is a combined measurement of maximum throughput and fairness, is evaluated for best-effort traffic. DSFN improves the FSSE by 100% to 370%, for a certain set of test cases, in comparison to the dynamic packet assignment (DPA) scheme, which combines packet scheduling with dynamic channel assignment (DCA).

Channel Assignment for Throughput Optimization in Multichannel Multiradio Wireless Mesh Networks Using Network Coding

Abstract: Compared to single-hop networks such as WiFi, multihop infrastructure wireless mesh networks (WMNs) can potentially embrace the broadcast benefits of a wireless medium in a more flexible manner Rather than being point-to-point, links in the WMNs may originate from a single node and reach more than one other node Nodes located farther than a one-hop distance and overhearing such transmissions may opportunistically help relay packets for previous hops This phenomenon is called opportunistic overhearing/listening With multiple radios, a node can also improve its capacity by transmitting over multiple radios simultaneously using orthogonal channels Capitalizing on these potential advantages requires effective routing and efficient mapping of channels to radios (channel assignment (CA)) While efficient channel assignment can greatly reduce interference from nearby transmitters, effective routing can potentially relieve congestion on paths to the infrastructure Routing, however, requires that only packets pertaining to a particular connection be routed on a predetermined route Random network coding (RNC) breaks this constraint by allowing nodes to randomly mix packets overheard so far before forwarding A relay node thus only needs to know how many packets, and not which packets, it should send We mathematically formulate the joint problem of random network coding, channel assignment, and broadcast link scheduling, taking into account opportunistic overhearing, the interference constraints, the coding constraints, the number of orthogonal channels, the number of radios per node, and fairness among unicast connections Based on this formulation, we develop a suboptimal, auction-based solution for overall network throughput optimization Performance evaluation results show that our algorithm can effectively exploit multiple radios and channels and can cope with fairness issues arising from auctions Our algorithm also shows promising gains over traditional routing solutions in which various channel assignment strategies are used