Dual Priority Scheduling Based on Power Adjustment Context Switching for Ubiquitous Sensor Network

SUMMARY Ubiquitous Sensor NetworkUSN1%99%

SUMMARYPower Adjustment Dual Priority Scheduler(PA-DPS)USNPA-DPSPA-DPS1%40%

Key words:Ubiquitous sensor networks, dual priority schedule, operating system

1.Introduction QoS.

TinyOSUSNOSOSMANTIS

USN1%USN99%95%uAMCU

USNRFUSN

2.USN(DPS)DPSworst case execution time(WCET)(WCET)USNUSN 1%

power_adjust()power_adjust()MCUDPSlower run queue(LRQ)upper run queue(URO)

periodic ready ready(PRQ),sporadic ready queue(SRQ)PRQSRQ FIFO(context-switching free)PRQ

PRQPRQsporadic tasksPOWER IDLEpower_adjust()

2ijWAITPRQT(j)T(i)1us32bit16us6016bitT(i,k-2)2Ci

SRQT(1)T(1)T(j,k-1)CjT(1)SRQPRQPRQ

power_adjust()

KE_ADC_COMPLETEDADpa_temp_detecttemp_detectpower_adjust()ADCtemp_detect

48-bitMAC6-bitdigital to analog converter(DAC)4-bit8051128kMAC24MHz416-bitMACcyclic redundancy check(CRC)MAC

5PA-DPSpower controllable hardware component(PCHC)power management unit(PMU)PCHChardware definition files(HDF)hardware abstractin library (HAL)HDFHALapplication programming interface(API)PA-DPSHALCMAC

4.Experimental Results(I)(t)USNUSN

1RFFIFOMCUsleep()

USN720.25%

0.25%99.751011uAAA(3000mAhr)117

30%PA-DPS7871%

5.Conclusion PA-DPS1%PA-DPS30~40%PA-DPS