# US 2019/0167200 A1 · Bio-signal quality assessment apparatus and bio-signal quality assessment method > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2019/0167200 A1 - Document ID: US20190167200A1 - Status: Published application - Kind: A1 - Application number: 16/200,141 - Filed: 2018-11-26 - Published: 2019-06-06 - Earliest claimed: 2017-12-01 - Assignees: Samsung Electronics Co., Ltd. - Applicants: Samsung Electronics Co., Ltd. - Inventors: Dae Geun JANG; Ui Kun KWON; Seung Keun YOON - Web page: https://patentgrep.com/patent/US20190167200A1 ## CPC - A61B 5/7221: {Determining signal validity, reliability or quality (preventing, reducing or removing noise induced by motion artefacts A61B5/7207; noise originating from a therapeutic or surgical apparatus A61B5/7217)} - A61B 5/0205: Simultaneously evaluating both cardiovascular conditions and different types of body conditions, e.g. heart and respiratory condition - A61B 5/7246: {using correlation, e.g. template matching or determination of similarity} - G16H 40/63: for local operation - A61B 5/02405: {Determining heart rate variability} - A61B 5/02416: {using photoplethysmograph signals, e.g. generated by infrared radiation (A61B5/14552 takes precedence)} - A61B 5/1102: {Ballistocardiography} - A61B 5/35: by template matching - A61B 7/04: Electric stethoscopes - A61B: DIAGNOSIS; SURGERY; IDENTIFICATION (usefulness limited to only animals A61D) - G16H: HEALTHCARE INFORMATICS, i.e. INFORMATION AND COMMUNICATION TECHNOLOGY [ICT] SPECIALLY ADAPTED FOR THE HANDLING OR PROCESSING OF MEDICAL OR HEALTHCARE DATA ## Abstract A bio-signal quality assessment apparatus may include: a bio-signal obtainer configured to obtain a bio-signal; and a processor configured to extract periodic signals from the obtained bio-signal, and determine a signal quality index based on at least one of similarity between the extracted periodic signals and signal variability of the obtained bio-signal. ## Claims ### Claim 1 A bio-signal quality assessment apparatus, comprising: a bio-signal obtainer configured to obtain a bio-signal; and a processor configured to extract periodic signals from the obtained bio-signal, and determine a signal quality index based on at least one of similarity between the extracted periodic signals and signal variability of the obtained bio-signal. ### Claim 2 (depends on 1) The apparatus of claim 1, wherein in response to at least one of the extracted periodic signals having a different duration from other periodic signals, the processor performs preprocessing on the at least one extracted periodic signal to calculate the similarity between the extracted periodic signals. ### Claim 3 (depends on 2) The apparatus of claim 2, wherein the processor performs resampling on the extracted periodic signals so that each of the extracted periodic signals has an equal number of samples N. ### Claim 4 (depends on 2) The apparatus of claim 2, wherein the processor determines a similarity evaluation period in each of the extracted periodic signals, and calculates the similarity between the extracted periodic signals in the determined similarity evaluation period. ### Claim 5 (depends on 1) The apparatus of claim 1, wherein the processor calculates the similarity between the extracted periodic signals which are apart from each other by a predetermined distance. ### Claim 6 (depends on 5) The apparatus of claim 5, wherein the processor calculates the similarity between the extracted periodic signals and a reference signal, and the processor determines, as the reference signal, an average signal of the extracted periodic signals which is obtained by superimposing the extracted periodic signals. ### Claim 7 (depends on 5) The apparatus of claim 5, wherein the processor determines the signal quality index based on statistical information of the calculated similarity between the periodic signals. ### Claim 8 (depends on 5) The apparatus of claim 5, wherein the processor determines the signal quality index based on a combination of two or more K-adjacent similarities having different K values, and wherein the K values indicate distance between the extracted periodic signals. ### Claim 9 (depends on 1) The apparatus of claim 1, wherein the processor determines a signal analysis period so that at least one of the periodic signals is to be included. ### Claim 10 (depends on 1) The apparatus of claim 1, wherein the processor calculates the signal variability, including at least one of amplitude variability and time variability of the obtained bio-signal, and determines the signal quality index based on the calculated signal variability. ### Claim 11 (depends on 10) The apparatus of claim 10, wherein the processor calculates a standard deviation or a coefficient of variation of at least one of amplitudes and durations of the extracted periodic signals and calculates the signal quality index based on the calculated standard deviation or the calculated coefficient of variation. ### Claim 12 (depends on 10) The apparatus of claim 10, further comprising an output interface configured to output at least one of the obtained bio-signal, the extracted periodic signals, a similarity evaluation period, a signal analysis period, a reference signal, the similarity between the periodic signals, the signal variability, and the signal quality index. ### Claim 13 (depends on 1) The apparatus of claim 1, wherein the bio-signal includes at least one of electrocardiogram (ECG), photoplethysmography (PPG), ballistocardiogram (BCG), a heart sound. ### Claim 14 A bio-signal quality assessment method, comprising: obtaining a bio-signal; and extracting periodic signals from the obtained bio-signal; and determining a signal quality index based on at least one of similarity between the extracted periodic signals and signal variability of the obtained bio-signal. ### Claim 15 (depends on 14) The method of claim 14, further comprising, in response to at least one of the extracted periodic signals having a different duration from other periodic signals, preprocessing the at least one extracted periodic signal to calculate the similarity between the extracted periodic signals. ### Claim 16 (depends on 15) The method of claim 15, wherein the preprocessing comprises resampling the extracted periodic signals so that each of the extracted periodic signals has an equal number of samples N. ### Claim 17 (depends on 15) The method of claim 15, wherein the preprocessing comprises determining a similarity evaluation period in each of the extracted periodic signals, and calculating the similarity between the extracted periodic signals in the determined similarity evaluation period. ### Claim 18 (depends on 14) The method of claim 14, wherein the determining the signal quality index further comprises calculating the similarity between the extracted periodic signals which are apart from each other by a predetermined distance. ### Claim 19 (depends on 18) The method of claim 18, wherein the determining the signal quality index further comprises calculating the similarity between the extracted periodic signals and a reference signal, and the calculating the similarity further comprises determining, as the reference signal, an average signal of the extracted periodic signals which is obtained by superimposing the extracted periodic signals. ### Claim 20 (depends on 18) The method of claim 18, wherein the determining the signal quality index comprises determining the signal quality index based on at least one of a combination of two or more K-adjacent similarities having different K values, and statistical information of the calculated similarity between the extracted periodic signals, wherein the K values indicate distance between the extracted periodic signals. ### Claim 21 (depends on 14) The method of claim 14, wherein the determining the signal quality index comprises determining the signal quality index by calculating signal variability, including at least one of amplitude variability and time variability of the obtained bio-signal, and determining the signal quality index based on the calculated signal variability. ### Claim 22 (depends on 21) The apparatus of claim 21, wherein the determining the signal quality index comprises: determining a standard deviation or a coefficient of variation of at least one of amplitudes and durations of the extracted periodic signals; and determining the signal quality index based on the determined standard deviation or the determined coefficient of variation.