Abstract: A physiological signal sensor to measure life signs includes at least one first and one second Doppler detectors, at least one first amplification filter, at least one second amplification filter, a processor, and a transceiver. Data from the physiological signal sensor is sent to the first and second Doppler detectors to detect first and second physiological signals from different locations on a living body. The two physiological signals are sent to the first and second amplification filters and amplified and filtered, and converted to obtain a first and second digital sensed signal. Digital signal processing is carried out on the digital sensed signals to obtain first and second physiological information which are outputted via the transceiver.