A portable device is provided. The portable device includes a power receiving unit configured to receive a first energy or a second energy from a wireless power transmitter, the first energy being used to perform a communication function and a control function, the second energy being used to charge a battery, and the wireless power transmitter being configured to wirelessly transmit a power, a voltage generator configured to generate a wake-up voltage from the first energy, or to generate a voltage for charging the battery from the second energy, a controller configured to perform the communication function and the control function, the controller being activated by the wake-up voltage, and a communication unit configured to perform a communication with the wireless power transmitter based on a control of the controller.