Wakeup Scheduling in Wireless Sensor Networks Mobihoc ‘06 Abtin Kesharvarzian, et al. Robert Bosch Corporation

Introduction Wireless Sensor Network 2 main categories Energy efficient Transfer delay sensitive (bidirectional delay guarantee) 2 main categories Scheduled wakeups Wakeup on-demand (out-of-band wakeup) Can be optimal in terms of delay and energy Cost issue limits range and reliability

Modeling D◄ Level : hop from base station D► Wakeup τ Time

Wakeup patterns - Fully Synchronized Pattern Fixed-power case Fixed-delay case Assumption wakeup cost = 15µC Battery Capacity = (2.4*108)E0 Fixed-Power Case h = 4 Teff = 2s Fixed-Delay Case max(D► ,D◄) <= 1

Wakeup patterns – Shifted Even & Odd Pattern Fixed-power case Fixed-delay case Assumption wakeup cost = 15µC Battery Capacity = (2.4*108)E0 Fixed-Power Case h = 4 Teff = 2s Fixed-Delay Case max(D► ,D◄) <= 1

Wakeup patterns – Ladder Wakeup Pattern Fixed-power case Fixed-delay case Assumption wakeup cost = 15µC Battery Capacity = (2.4*108)E0 Fixed-Power Case h = 4 Teff = 2s Fixed-Delay Case max(D► ,D◄) <= 1

Wakeup patterns – Two-Ladders Pattern Fixed-power case Fixed-delay case Assumption wakeup cost = 15µC Battery Capacity = (2.4*108)E0 Fixed-Power Case h = 4 Teff = 2s Fixed-Delay Case max(D► ,D◄) <= 1

Wakeup patterns - Fully Synchronized Pattern Fixed-power case Fixed-delay case Assumption wakeup cost = 15µC Battery Capacity = (2.4*108)E0 Fixed-Power Case h = 4 Teff = 2s Fixed-Delay Case max(D► ,D◄) <= 1

Multi-Parent Method Assumption Divide the nodes into multiple disjoint groups Each node has parents of # of groups

Wakeup patterns – Multi-parent Method Fixed-power case Fixed-delay case Assumption wakeup cost = 15µC Battery Capacity = (2.4*108)E0 Fixed-Power Case h = 4 Teff = 2s Fixed-Delay Case max(D► ,D◄) <= 1 is the same as single parent method

Evaluation & Comparison

Evaluation & Comparison

Evaluation & Comparison

Evaluation & Comparison

Conclusion Wakeup schemes can obtain both bidirectional delay guarantee & energy efficiency

Extra slides

Assumption wakeup cost = 15µC Battery Capacity = (2.4*108)E0 Fixed-Power Case h = 4 Teff = 2s Fixed-Delay Case max(D► ,D◄) <= 1