Low cost respiration sensing using mm wave radar
A biological monitoring device, including a housing and a distance sensor in connection with the housing, where the distance sensor is configured to emit an electromagnetic wave into a local environment and to sense the electromagnetic wave reflected off an object in the local environment and within a detection field of the distance sensor. A controller is communicatively in connection with the distance sensor. The controller is configured to control the distance sensor to emit the electromagnetic wave, detect a change in distance between the biological monitoring device and the object based on the electromagnetic wave emitted by the distance sensor, and determine a rate of a periodic biological movement based on the change of distance.
1 . A biological monitoring device, comprising:
a housing;
a distance sensor in connection with the housing, wherein the distance sensor is configured to emit an electromagnetic wave into a local environment and to sense the electromagnetic wave reflected off an object in the local environment and within a detection field of the distance sensor; and
a controller communicatively in connection with the distance sensor, wherein the controller is configured to:
control the distance sensor to emit the electromagnetic wave;
detect a change in distance between the biological monitoring device and the object based on the electromagnetic wave emitted by the distance sensor; and
determine a rate of a periodic biological movement based on the change of distance; and
modulate a wavelength of the electromagnetic wave to embed a data packet within the electromagnetic wave.
2 . The biological monitoring device of claim 1 , further comprising:
a motion detection sensor configured to sense a user movement.
3 . The biological monitoring device of claim 2 , wherein the controller is configured to:
determine whether the user movement sensed by the motion detection sensor is an internal thoracic cavity movement or an external body movement; and
filter the change in distance detected during the external body movement from the determination of the rate of the periodic biological movement.
4 . The biological monitoring device of claim 2 , wherein the controller is configured to:
determine whether the user movement sensed by the motion detection sensor is an internal thoracic cavity movement or an external body movement;
correlate a magnitude of the user movement sensed by the motion detection sensor and a magnitude of change in distance sensed by the distance sensor in response to determination that the user movement is the internal thoracic cavity movement;
determine whether the object is static or non-static based on the correlation between the magnitude of movement and the magnitude of change in distance; and
filter the change in distance from the determination of the rate of the periodic biological movement in response to the determination that the object is non-static.
5 . The biological monitoring device of claim 1 , wherein the data packet includes the rate of the periodic biological movement.
6 . The biological monitoring device of claim 1 , wherein the rate of the periodic biological movement is one of a heart rate or a respiration rate.
7 . The biological monitoring device of claim 1 , wherein a data packet is not communicated via a communication module in addition to the distance sensor.
8 . The biological monitoring device of claim 1 , wherein the distance sensor is a phased array having at least one transmitter element and a plurality of sensor elements, and wherein the at least one transmitter element is configured to emit the electromagnetic wave and each sensor element of the plurality of sensor elements is configured to sense the electromagnetic wave reflected off the object.
9 . The biological monitoring device of claim 1 , wherein the controller is configured to:
control the at least one transmitter element to emit the electromagnetic wave; and
compare the change in distance between the biological monitoring device and the object based on the electromagnetic wave emitted by the at least one transmitter element.
10 . The biological monitoring device of claim 1 , where in the controller is configured to:
determine whether the object is static or non-static based on the change in distance between the biological monitoring device and the object; and
filter the change in distance from the determination of the rate of the periodic biological movement in response to the determination that the object is non-static.
11 . A method for monitoring a periodic biological movement, comprising:
emitting an electromagnetic wave into a local environment;
sensing the electromagnetic wave reflected off an object located in the local environment;
detecting a change in distance between an origin of the electromagnetic wave emission and the object in the local environment based on the electromagnetic wave;
determining whether the object located in the local environment is static or non-static based on the change in distance be ween the origin of the electromagnetic wave emission and the object;
determining a rate of the periodic biological movement based on the change in distance between the origin of the electromagnetic wave emission and the object; and
filtering the change in distance from the determination of the rate of the periodic biological movement in response to the determination that the object is non-static.
12 . The method of claim 11 , further comprising:
sensing a patient movement;
determining whether the patient movement sensed is an internal thoracic cavity movement or an external body movement; and
filtering the change in distance detected during the external body movement from determining the rate of the periodic biological movement.
13 . The method of claim 11 , further comprising:
communicating a data packet via a modulation of a wavelength of the electromagnetic wave, wherein the data packet includes the rate of the periodic biological movement.
14 . A monitoring system for a patient, comprising:
a housing;
a distance sensor in connection with the housing, wherein the distance sensor is configured to emit an electromagnetic wave into a local environment away from the patient and to sense the electromagnetic wave reflected off an object in the local environment and within a detection field of the distance sensor; and
a first controller communicatively in connection with the distance sensor, wherein the first controller is configured to:
control the distance sensor to emit the electromagnetic wave;
detect a change in distance between the distance sensor and the object based on the electromagnetic wave emitted by the distance sensor; and
determine a rate of a periodic biological movement of the patient based on the change of distance.
15 . The patient monitoring system of claim 14 , wherein the second controller is configured to monitor the rate of the periodic biological movement relative to a range of stored rates.
16 . The patient monitoring system of claim 14 , wherein the second controller is configured to store the data packet in a patient medical file.
17 . The patient monitoring system of claim 14 , wherein the data packet includes the rate of the periodic biological movement, and wherein the second controller is configured to display the periodic biological movement on a display device in communication with the second controller.
18 . The patient monitoring system of claim 14 , wherein the housing is configured to be worn by a user, and wherein the distance sensor is configured to emit the electromagnetic wave along an emission axis oriented away from the patient.
19 . The patient monitoring system of claim 14 , wherein the controller is further configured to:
identify the periodic biological movement as being attributed to an internal thoracic cavity and filtering non-conforming movements attributed to the movement of the object or an external body movement of the patient.
20 . The patient monitoring system of claim 14 , wherein the object in the local environment is fixed over a monitoring period of the periodic biological movements.