Design of a low power smart wireless system used for multisensor monitoring

In this work, a design of low power wireless system for multisensors monitoring has been presented. The main purpose of this research is to develop an efficient telemetry system for recording various biomedical signals such as pressure and temperature. The system reads data from two types of sensors, resistive and capacitive. Anderson circuit configuration has been used for resistive sensor, since it offers linear like behavior. The capacitive interface is based on capacitance-frequency-voltage conversion that uses phase lock loop (PLL) to convert the frequency to voltage. Two mechanisms have been adopted to reduce the overall power consumption. These are power scheduling and wakeup circuit for the capacitive interface. The first one is implemented fully by the microcontroller unit (MCU) in order to switch on/off all the system units. A wakeup circuit has been designed to interrupt the MCU when it is in the sleep mode and the capacitive samples are changing significantly