摘要:
In a sensor node SN driven by a secondary battery, a charge/discharge control circuit can be realized and an unnecessary circuit in the sensor node can be eliminated for its miniaturization. The charge/discharge control circuit and the sensor node have a comparator for monitoring a battery voltage, a control circuit for converting an output of the comparator into an interrupt signal, a micro controller for performing charge/discharge control only when detecting the interrupt signal, and a switch turned ON or OFF under control of the micro controller. When the battery voltage is not lower than a first predetermined voltage, the switch is turned OFF to thereby stop charging operation. When the battery voltage is not higher than a second predetermined voltage, the switch is turned OFF to stop discharging operation. A circuit necessary in a charge mode is provided in a charger side.
摘要:
To secure a stable radio-communication performance in a sensor node, the sensor node with a radio-communication circuit and a sensor, for transmitting data measured by the sensor through radio-communication, includes a first board BO2 on which an antenna ANT1 connected to the radio-communication circuit is placed, a case CASE1 containing the first board BO2, and a band that is attached to the case CASE1 so as to fix the case CASE1 to the skin. The antenna ANT1 is placed in an upper portion of the case CASE1, which corresponds to a 12 o'clock direction of a wristwatch.
摘要:
The precision of measuring biometric information is enhanced while suppressing the consumption of a battery in a sensor node. In a method of measuring the biometric information in a sensor node including a controller for driving a sensor to measure biometric information, the controller supplies power from a battery to an acceleration sensor for detecting the movement of a living body to detect the movement of the living body, the controller determines whether or not measurement by a pulsebeat sensor is possible based on the detected movement of the living body (P330), and shuts off power to the acceleration sensor having a power consumption lower than that of the pulsebeat sensor when the determination results show that measurement is possible, and thereafter supplying power to the pulsebeat sensor having a power consumption larger than that of the acceleration sensor to measure the biometric information (P340).
摘要:
The precision of measuring biometric information is enhanced while suppressing the consumption of a battery in a sensor node. In a method of measuring the biometric information in a sensor node including a controller for driving a sensor to measure biometric information, the controller supplies power from a battery to an acceleration sensor for detecting the movement of a living body to detect the movement of the living body, the controller determines whether or not measurement by a pulsebeat sensor is possible based on the detected movement of the living body (P330), and shuts off power to the acceleration sensor having a power consumption lower than that of the pulsebeat sensor when the determination results show that measurement is possible, and thereafter supplying power to the pulsebeat sensor having a power consumption larger than that of the acceleration sensor to measure the biometric information (P340).
摘要:
Provided is a sensor node including: a sensor for measuring biological information; a CPU for acquiring data by driving the sensor; a wireless communication unit for transmitting the data acquired by the CPU; a battery for supplying the control unit, the wireless communication unit, and the sensor with electric power; a RAM for storing the data; a compression unit for compressing the data stored in the RAM when the wireless communication unit cannot carry out the transmission; and a flash memory for storing the compressed data, thereby storing as much sensing data as possible on the sensor node, which is limited in resources, and preventing loss of the sensing data.
摘要:
Provided is a sensor node including: a sensor for measuring biological information; a CPU for acquiring data by driving the sensor; a wireless communication unit for transmitting the data acquired by the CPU; a battery for supplying the control unit, the wireless communication unit, and the sensor with electric power; a RAM for storing the data; a compression unit for compressing the data stored in the RAM when the wireless communication unit cannot carry out the transmission; and a flash memory for storing the compressed data, thereby storing as much sensing data as possible on the sensor node, which is limited in resources, and preventing loss of the sensing data.
摘要:
A sensor node for intermittently sensing data in a short cycle includes a control unit for acquiring information by driving the sensor, a radio communication unit for transmitting the information acquired by the control unit and a battery for supplying the control unit. The control unit includes a clock supply unit (RTC) for supplying the control unit with clocks at a predetermined frequency. A sensor control unit starts the supply of power to the sensor when the measurement period has begun, maintains the power supply to the sensor even if the control unit has shifted to the standby state during the measurement period, and shuts down the power supply to the sensor when the measurement period has been completed. A measurement unit is also provided for acquiring information from the sensor every time the latter has shifted to the operational state.
摘要:
A sensor node for intermittently sensing data in a short cycle includes a control unit for acquiring information by driving the sensor, a radio communication unit for transmitting the information acquired by the control unit and a battery for supplying the control unit. The control unit includes a clock supply unit (RTC) for supplying the control unit with clocks at a predetermined frequency. A sensor control unit starts the supply of power to the sensor when the measurement period has begun, maintains the power supply to the sensor even if the control unit has shifted to the standby state during the measurement period, and shuts down the power supply to the sensor when the measurement period has been completed. A measurement unit is also provided for acquiring information from the sensor every time the latter has shifted to the operational state.
摘要:
To secure a stable radio-communication performance in a sensor node, the sensor node with a radio-communication circuit and a sensor, for transmitting data measured by the sensor through radio-communication, includes a first board BO2 on which an antenna ANT1 connected to the radio-communication circuit is placed, a case CASE1 containing the first board BO2, and a band that is attached to the case CASE1 so as to fix the case CASE1 to the skin. The antenna ANT1 is placed in an upper portion of the case CASE1, which corresponds to a 12 o'clock direction of a wristwatch.
摘要:
An ATM switching system comprises a switch unit including a plurality of input ports and a plurality of output ports having the same cell transmission rate, and a multiplexer for multiplexing cell trains outputted from at least two output ports into a single cell train and outputting the cell train to a high-speed output line (and/or a demultiplexer for demultiplexing a cell train from an output port into a plurality of cell trains and outputting the cell trains to a plurality of low-speed output lines). The switch unit includes a buffer memory for temporarily storing cells inputted from the input ports while forming a queue chain for each output line to which each cell is to be outputted, a demultiplexer for distributing the cells read from the buffer memory among the output ports in circulation, and a buffer memory control circuit for controlling the write and read operation of cells with the shared buffer memory. The buffer memory control circuit has a control table device for outputting an identifier of an output line to which the cells read from the shared buffer memory are to be outputted, and cells are read from the chain designated by the output line identifier outputted from the control table device.