Abstract: A wireless sensor for a wireless sensor network includes a sensor unit performing sensing to sense environment and/or circumstance, first routing to send first sensing information to a server according to routing information, and second routing to send second sensing information from another wireless sensor to the server according to the routing information, when being supplied with power from a power source, a timer including a capacitor to be charged by the power and performs a time limit operation due to self-discharge thereof, a first control switch controlling power supplying to the timer to make the timer perform the time limit operation at a set time, a rectifier converting a radio signal from the another wireless sensor into power, and a second control switch starting power supplying to the sensor unit, upon receiving the control signal of the rectifier during the time limit operation.

Abstract: A wireless sensor for a wireless sensor network includes a sensor unit performing sensing to sense environment and/or circumstance, first routing to send first sensing information to a server according to routing information, and second routing to send second sensing information from another wireless sensor to the server according to the routing information, when being supplied with power from a power source, a timer including a capacitor to be charged by the power and performs a time limit operation due to self-discharge thereof, a first control switch controlling power supplying to the timer to make the timer perform the time limit operation at a set time, a rectifier converting a radio signal from the another wireless sensor into power, and a second control switch starting power supplying to the sensor unit, upon receiving the control signal of the rectifier during the time limit operation.