An improved on-chip CMOS astable multivibrator is proposed, which overcomes the shortcomings of the traditional one that the signal duty-cycle is depending on model parameters, and generates stable clock signal with d...An improved on-chip CMOS astable multivibrator is proposed, which overcomes the shortcomings of the traditional one that the signal duty-cycle is depending on model parameters, and generates stable clock signal with duty-cycle equaling 50%. The latch-up effect has been prevented on the improved circuit. It is extremely important that all the excellent performances of the improved astable multivibrator have been achieved with a dynamic power consumption equaling its predecessor one. The advantage of the structure has been verified by SPICE simulation.展开更多
Many energy efficiency asynchronous duty-cycle MAC(media access control) protocols have been proposed in recent years.However,in these protocols,wireless sensor nodes almost choose their wakeup time randomly during th...Many energy efficiency asynchronous duty-cycle MAC(media access control) protocols have been proposed in recent years.However,in these protocols,wireless sensor nodes almost choose their wakeup time randomly during the operational cycle,which results in the packet delivery latency increased significantly on the multiple hops path.To reduce the packet delivery latency on multi-hop path and energy waste of the sender's idle listening,a new low latency routing-enhanced asynchronous duty-cycle MAC protocol was presented,called REA-MAC.In REA-MAC,each sensor node decided when it waked up to send the beacon based on cross-layer routing information.Furthermore,the sender adaptively waked up based on the relationship between the transmission request time and the wakeup time of its next hop node.The simulation results show that REA-MAC reduces delivery latency by 60% compared to RI-MAC and reduces 8.77% power consumption on average.Under heavy traffic,REA-MAC's throughput is 1.48 times of RI-MAC's.展开更多
文摘An improved on-chip CMOS astable multivibrator is proposed, which overcomes the shortcomings of the traditional one that the signal duty-cycle is depending on model parameters, and generates stable clock signal with duty-cycle equaling 50%. The latch-up effect has been prevented on the improved circuit. It is extremely important that all the excellent performances of the improved astable multivibrator have been achieved with a dynamic power consumption equaling its predecessor one. The advantage of the structure has been verified by SPICE simulation.
基金Projects(61103011,61170261) supported by the National Natural Science Foundation of China
文摘Many energy efficiency asynchronous duty-cycle MAC(media access control) protocols have been proposed in recent years.However,in these protocols,wireless sensor nodes almost choose their wakeup time randomly during the operational cycle,which results in the packet delivery latency increased significantly on the multiple hops path.To reduce the packet delivery latency on multi-hop path and energy waste of the sender's idle listening,a new low latency routing-enhanced asynchronous duty-cycle MAC protocol was presented,called REA-MAC.In REA-MAC,each sensor node decided when it waked up to send the beacon based on cross-layer routing information.Furthermore,the sender adaptively waked up based on the relationship between the transmission request time and the wakeup time of its next hop node.The simulation results show that REA-MAC reduces delivery latency by 60% compared to RI-MAC and reduces 8.77% power consumption on average.Under heavy traffic,REA-MAC's throughput is 1.48 times of RI-MAC's.