Compact, energy efficient physiological parameter sensor system
A physiological parameter sensor system includes a housing with a first cell and a plurality of second cells. A first sensor system element (either an emitter or a detector) resides in the first cell. Second sensor system elements reside in at least some of the second cells. If the first sensor system element is an emitter, each second sensor system element is a detector, and vice versa. The housing is conformable to the contours of a patient to ensure that the sensor system elements are closely coupled to the patient's skin. The system identifies the emitter which yields the best quality signal at the detector (or the detector which receives the best quality signal from the emitter). The system then uses only the identified emitter/detector pair. The system is compact, places only modest demands on battery power, and tolerates being positioned at a nonoptimal locations on the patient's body.
1. A physiological parameter sensor system comprising:
a housing having a patient facing side having a baseline configuration, an opposite side longitudinally spaced from the patient facing side, and a set of longitudinally extending sidewalls which cooperate with the patient facing side and the opposite side to define a first cell and a plurality of second cells which circumscribe the first cell;
a first sensor system element residing in the first cell, the first sensor system element being an emitter;
two or more second sensor system elements residing in the plurality of second cells, each second sensor system element being a detector;
the patient facing side of the housing being conformable to a non-baseline configuration; and
a processor adapted to:
A) cause the emitter to emit a test signal,
B) sample each detector for a return signal associated with the test signal,
C) select one detector to be a companion detector to the emitter based on quality of the return signal, and
D) deselect, at least temporarily, all detectors other than the companion detector;
wherein some of the set of longitudinally extending sidewalls are intercell sidewalls common to adjacent cells; and
wherein the intercell sidewalls are configured to stretch and compress in a longitudinal direction.
2. The sensor system of claim 1 wherein the baseline configuration is a plane, and the non-baseline configuration is a plane which is nonparallel to the baseline plane.
3. The sensor system of claim 1 wherein the baseline configuration is a plane and the non-baseline configuration is nonplanar.
4. The sensor system of claim 1 wherein the opposite side of the housing is a cover, and each sidewall extends longitudinally from the cover to a sidewall terminus which is joined to a closure element which defines the patient side of the housing.
5. The sensor system of claim 1 wherein the opposite side of the housing is a cover, and each sidewall extends longitudinally from the cover to a sidewall free terminus which defines the patient side of the housing.
6. The sensor system of claim 1 wherein steps A, B, C and D are a preparatory sequence and the processor is adapted to, subsequent to the preparatory sequence:
E) cause the emitter to emit an operational signal, and
F) employ the return signal detected by the selected detector as a result of the operational signal from the emitter.
7. The sensor system of claim 6 wherein the processor is adapted to periodically repeat the preparatory sequence.
8. The sensor system of claim 1 wherein the step of deselecting all detectors other than the companion detector is a step of de-powering all detectors other than the companion detector.
9. The sensor system of claim 1 wherein when the housing is applied to a patient the non-baseline configuration follows a contour of the patient.
10. The sensor system of claim 1 wherein the first sensor system element has a baseline line of sight and a non-baseline line of sight, and the nonbaseline line of sight differs from the baseline line of sight.
11. The sensor system of claim 1 wherein some of the sidewalls are noncommon intercell sidewalls connected to an adjacent intercell sidewall by a web.
12. The sensor system of claim 1 wherein:
two or more of the plurality of second cells are longitudinal aligned in the baseline configuration; and
at least one cell of the plurality of second cells is longitudinally nonaligned with other cells of the plurality of second cells in the non-baseline configuration.
13. The sensor system of claim 1 wherein:
the first cell is a central cell;
the plurality of second cells are radially adjacent to the first cell;
and
the sensor system includes the processor adapted to select a detector/emitter pair and to control an operational mode in which the emitter and detector of the selected pair are used, at least temporarily, to the exclusion of all other emitters and detectors.