A wireless communication apparatus , comprising: a wireless unit that performs a wireless communication with a different wireless communication apparatus; a control unit that controls the wireless unit ; a power switch unit that switches a power supplied from a battery to the wireless unit and the control unit ; a power supply control unit that controls an on/off operation of the power switch unit in accordance with a trigger for turning off the power supply and a trigger for turning on the power supply; and a timer unit that includes a register in which an expiration time value is stored, and that outputs the trigger for turning on the power supply to the power supply control unit when a count value of the register in the timer unit reaches the expiration time value, wherein when the wireless unit and the control unit are supplied with the power through the power switch unit in accordance with the trigger for turning on the power supply, the control unit starts controls of the wireless unit to receive a wireless signal transmitted from the different wireless communication apparatus, and the control unit then sets the expiration time value in the register of the timer unit when finishing the controls of the wireless unit and outputs the trigger for turning off the power supply to the power supply control unit , wherein the control unit , in a case where the wireless unit fails to receive a wireless signal transmitted from the different wireless communication apparatus or where the wireless unit does not receive a wireless signal transmitted from the different wireless communication apparatus within a regulated time, sets an increased expiration time value in the register, in comparison to a case otherwise. a wireless unit that performs a wireless communication with a different wireless communication apparatus; a control unit that controls the wireless unit ; a power switch unit that switches a power supplied from a battery to the wireless unit and the control unit ; a power supply control unit that controls an on/off operation of the power switch unit in accordance with a trigger for turning off the power supply and a trigger for turning on the power supply; and a timer unit that includes a register in which an expiration time value is stored, and that outputs the trigger for turning on the power supply to the power supply control unit when a count value of the register in the timer unit reaches the expiration time value, wherein when the wireless unit and the control unit are supplied with the power through the power switch unit in accordance with the trigger for turning on the power supply, the control unit starts controls of the wireless unit to receive a wireless signal transmitted from the different wireless communication apparatus, and the control unit then sets the expiration time value in the register of the timer unit when finishing the controls of the wireless unit and outputs the trigger for turning off the power supply to the power supply control unit , wherein the control unit , in a case where the wireless unit fails to receive a wireless signal transmitted from the different wireless communication apparatus or where the wireless unit does not receive a wireless signal transmitted from the different wireless communication apparatus within a regulated time, sets an increased expiration time value in the register, in comparison to a case otherwise. <EOS>