Patent ID: 7424379
Filing Date: 2008-09-09
Classification: H04B

Abstract:
1. An activity information meter comprising a measuring device and an output device which are formed separately and transmit measurement data and control data via a body as a medium, the measuring device comprising: a measurement section, an oscillation section for the measuring device, a modulation section for the measuring device, a current output section for the measuring device, a transmitting/receiving electrode for the measuring device, a transmitting electrode for the measuring device, a reference potential section for the measuring device, a voltage detection section for the measuring device, a demodulation section for the measuring device, a first selector, a second selector, a sixth selector, and a control section for the measuring device, the output device comprising: an oscillation section for the output device, a modulation section for the output device, a current output section for the output device, a transmitting/receiving electrode for the output device, a transmitting electrode for the output device, a reference potential section for the output device, a voltage detection section for the output device, a demodulation section for the output device, a third selector, a fourth selector, a fifth selector, a control section for the output device, and an output section, wherein the measurement section measures activity information as measurement data, the oscillation section for the measuring device generates an alternating current signal, the modulation section for the measuring device modulates the alternating current signal generated by the oscillation section for the measuring device into a modulated signal based on the measurement data measured by the measurement section, the current output section for the measuring device outputs a current corresponding to the modulated signal modulated by the modulation section for the measuring device, the transmitting/receiving electrode for the measuring device contacts a body part between one end part and another end part of a body to pass the current output from the current output section for the measuring device through the body and detect a change in potential which occurs in the body, the transmitting electrode for the measuring device contacts a body part between the one end part of the body and the transmitting/receiving electrode for the measuring device to pass the current output from the current output section for the measuring device through the body, the reference potential section for the measuring device has a reference potential, the voltage detection section for the measuring device detects a voltage based on the reference potential of the reference potential section for the measuring device and the change in potential in the body which has been detected by the transmitting/receiving electrode for the measuring device, the demodulation section for the measuring device demodulates the voltage detected by the voltage detection section for the measuring device into a demodulated signal, the first selector selects connection between the current output section for the measuring device and the transmitting/receiving electrode for the measuring device or connection between the current output section for the measuring device and the second selector, the second selector selects connection between the current output section for the measuring device and the transmitting electrode for the measuring device or connection between the current output section for the measuring device and the first selector, the sixth selector selects connection between the transmitting electrode for the measuring device and the voltage detection section for the measuring device or connection between the reference potential section for the measuring device and the voltage detection section for the measuring device, the control section for the measuring device controls the first selector to select connection between the current output section for the measuring device and the second selector, controls the second selector to select connection between the current output section for the measuring device and the first selector and controls the sixth selector to select connection between the reference potential section for the measuring device and the voltage detection section for the measuring device when the measuring device receives control data, while the control section for the measuring device issues the measurement data measured by the measurement section to the modulation section for the measuring device and controls the first selector to select connection between the current output section for the measuring device and the transmitting/receiving electrode for the measuring device, controls the second selector to select connection between the current output section for the measuring device and the transmitting electrode for the measuring device and controls the sixth selector to select connection between the transmitting electrode for the measuring device and the voltage detection section for the measuring device when the measuring device transmits the measurement data, the oscillation section for the output device generates an alternating current signal, the modulation section for the output device modulates the alternating current signal generated by the oscillation section for the output device into a modulated signal based on control data, the current output section for the output device outputs a current corresponding to the modulated signal modulated by the modulation section for the output device, the transmitting/receiving electrode for the output device contacts one end part of the body to pass the current output from the current output section for the output device through the body and detect a change in potential which occurs in the body, the transmitting electrode for the output device contacts another end part of the body to pass the current output from the current output section for the output device through the body, the reference potential section for the output device has a reference potential, the voltage detection section for the output device detects a voltage based on the reference potential of the reference potential section for the output device and the change in potential in the body which has been detected by the transmitting/receiving electrode for the output device, the demodulation section for the output device demodulates the voltage detected by the voltage detection section for the output device into a demodulated signal, the third selector selects connection between the current output section for the output device and the transmitting/receiving electrode for the output device or connection between the current output section for the output device and the fourth selector, the fourth selector selects connection between the current output section for the output device and the transmitting electrode for the output device or connection between the current output section for the output device and the third selector, the fifth selector selects connection between the transmitting electrode for the output device and the voltage detection section for the output device or connection between the reference potential section for the output device and the voltage detection section for the output device, the control section for the output device issues control data to the modulation section for the output device and controls the third selector to select connection between the current output section for the output device and the transmitting/receiving electrode for the measuring device, controls the fourth selector to select connection between the current output section for the output device and the transmitting electrode for the output device and controls the fifth selector to select connection between the transmitting electrode for the output device and the voltage detection section for the output device when the output device transmits the control data, while the control section for the output device controls the third selector to select connection between the current output section for the output device and the fourth selector, controls the fourth selector to select connection between the current output section for the output device and the third selector and controls the fifth selector to select connection between the reference potential section for the output device and the voltage detection section for the output device when the output device receives the measurement data, and the output section outputs measurement data corresponding to the demodulated signal demodulated by the demodulation section for the output device.