Exploiting Spectral Reuse in Resource Allocation, Scheduling,and Routing for IEEE Mesh Networks Lien-Wu Chen, Yu-Chee Tseng Department of Computer Science, National Chiao-Tung University Da-Wei Wang, and Jan-Jan Wu Institute of Information Science, Academia Sinica IEEE VTC 2007
Outline Introduction Related work Resource Allocation and Scheduling Schemes Routing Tree Construction Simulation Conclusion
Introduction The IEEE d specifies a centralized scheduling scheme for mesh networks The SSs notify the BS Data transfer requirements The quality of their links to their neighbors The BS uses the topology information along with the requirements of each SS to decide the routing and the scheduling
Background_ maintain routing tree BS broadcast MSH-CSCF (Mesh Centralized Scheduling Configuration) message to all SSs
Background_ uplink and downlink (1) BS collects MSH-CSCH: request (Mesh Centralized Scheduling) message from all SSs (2) BS broadcasts MSH-CSCH:grant to all SSs Request grant
Title: Interference-Aware IEEE WiMax Mesh Networks Authors: H.-Y. Wei, S. Ganguly, R. Izmailov, and Z. Haas. From: IEEE VTC’05 Related Work
the algorithm does not fully exploit spectral reuse and it is not load- aware Related Work
Title: Spatial Reuse in IEEE Based Wireless Mesh Networks Authors: L. Fu, Z. Cao, and P. Fan. From: IEEE ISCIT’05 Related Work
link 1,4,7 and link 2,5,8 are simultaneous, respectively L8 SS 8 SS 7 SS 6 SS 5 SS 4 SS 3 SS 2 SS 1 L7 L6L5L4L3L2L1
Related Work new
the algorithm does not fully exploit spectral reuse and it is not load- aware Although how to attach a new SS to a mesh tree is discussed, but scheduling is not addressed in that work Related Work
Resource Allocation and Scheduling Schemes_ goal First, dynamically adapt the bandwidths between uplink and downlink subchannels Second, proportionally allocate frame timeslots among SSs Finally, obtain higher gateway throughput based on the above two manners.
Resource Allocation and Scheduling Schemes_ System Model
Resource Allocation and Scheduling Schemes is uplink rate of SS i is uplink traffic demands of SS i is the demand of transmission time of SS i is the total uplink transmission time of the network is the total uplink transmission time of extended neighborhood of SS i
Resource Allocation and Scheduling Schemes time SS 1 addition The maximal transmission time for SS i = for non-real-time or best effort traffic
Resource Allocation and Scheduling Schemes, the bottleneck SS will see 100% busy carriers time
Resource Allocation and Scheduling Schemes Channel-Level Scheduling Link-Level Scheduling downlink time uplink Channel-Level Scheduling :
Resource Allocation and Scheduling Schemes_ link level scheduling Phase 1Phase 2
Resource Allocation and Scheduling Schemes
Routing Tree Construction
1
A={3,4,5,6,7} B={ } A={3,4,5,7} B={6 } Initial : is the highest data rate among links of SS j to its neighbors with less or equal hop count is uplink traffic demands of SS i,
Simulation System parameter : A single channel OFDM PHY A single BS ( node 0 ) 84 SSs ( node 1 ~ 84 ) Channel bandwidth is set to 50Mb/s Data rate of all links are the same The extended neighborhood of each SS includes one-hop and two-hop neighbors
Simulation_ Physical Layer Parameter
Simulation_ Burst Profile
Conclusion An integrated spectral reuse framework for centralized scheduling scheme and routing tree construction is developed This method is most complete in exploiting spectral reuse
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