Determining respiratory rate via impedance pneumography

A system for continuous monitoring a respiratory rate of a user using a wearable sensor device, the system comprising:

• the wearable sensor device comprising a memory, a processing unit coupled to the memory and executing instructions stored therein, a transmitter coupled to the memory and first and second electrodes coupled to the user, wherein a voltage signal of known impedance is used as an input signal, and wherein the wearable sensor device measures a differential voltage across the first and the second electrodes;
• and
• an analog-to-digital converter coupled to the first and second electrodes of the wearable sensor device, wherein the analog-to-digital converter samples the differential voltage measured by the first and second electrodes to produce an output signal;
• wherein the processing unit coupled to the wearable sensor device processes the output signal to detect a breath of the user by executing instructions comprising:
• determine a local maximum using the output signal,
• determine transitioning of the samples from below a midpoint value to above the midpoint value using the output signal, when the local maximum of the output signal is above a midpoint between maximum value of previous breath and minimum value of previous breath, wherein a positive voltage transition through the midpoint indicates the breath of the user;
• and
• compare the local maximum with a predetermined threshold when the local maximum of the output signal is below the midpoint between the previous breath's maximum and minimum value, wherein the local maximum above the predetermined threshold indicates the breath of the user;
• wherein the breath of the user is utilized to determine the respiratory rate of the user, which is transmitted to another user or device by the transmitter.