PMID- 33922563
OWN - NLM
STAT- MEDLINE
DCOM- 20210503
LR  - 20210518
IS  - 1424-8220 (Electronic)
IS  - 1424-8220 (Linking)
VI  - 21
IP  - 9
DP  - 2021 Apr 23
TI  - Automated Non-Contact Respiratory Rate Monitoring of Neonates Based on 
      Synchronous Evaluation of a 3D Time-of-Flight Camera and a Microwave 
      Interferometric Radar Sensor.
LID - 10.3390/s21092959 [doi]
LID - 2959
AB  - This paper introduces an automatic non-contact monitoring method based on the 
      synchronous evaluation of a 3D time-of-flight (ToF) camera and a microwave 
      interferometric radar sensor for measuring the respiratory rate of neonates. The 
      current monitoring on the Neonatal Intensive Care Unit (NICU) has several issues 
      which can cause pressure marks, skin irritations and eczema. To minimize these 
      risks, a non-contact system made up of a 3D time-of-flight camera and a microwave 
      interferometric radar sensor is presented. The 3D time-of-flight camera delivers 
      3D point clouds which can be used to calculate the change in distance of the 
      moving chest and from it the respiratory rate. The disadvantage of the ToF camera 
      is that the heartbeat cannot be determined. The microwave interferometric radar 
      sensor determines the change in displacement caused by the respiration and is 
      even capable of measuring the small superimposed movements due to the heartbeat. 
      The radar sensor is very sensitive towards movement artifacts due to, e.g., the 
      baby moving its arms. To allow a robust vital parameter detection the data of 
      both sensors was evaluated synchronously. In this publication, we focus on the 
      first step: determining the respiratory rate. After all processing steps, the 
      respiratory rate determined by the radar sensor was compared to the value 
      received from the 3D time-of-flight camera. The method was validated against our 
      gold standard: a self-developed neonatal simulation system which can simulate 
      different breathing patterns. In this paper, we show that we are the first to 
      determine the respiratory rate by evaluating the data of an interferometric 
      microwave radar sensor and a ToF camera synchronously. Our system delivers very 
      precise breaths per minute (BPM) values within the norm range of 20-60 BPM with a 
      maximum difference of 3 BPM (for the ToF camera itself at 30 BPM in normal mode). 
      Especially in lower respiratory rate regions, i.e., 5 and 10 BPM, the synchronous 
      evaluation is required to compensate the drawbacks of the ToF camera. In the norm 
      range, the ToF camera performs slightly better than the radar sensor.
FAU - Gleichauf, Johanna
AU  - Gleichauf J
AUID- ORCID: 0000-0002-2702-1077
AD  - Nuremberg Institute of Technology, 90489 Nurnberg, Germany.
FAU - Herrmann, Sven
AU  - Herrmann S
AUID- ORCID: 0000-0002-0507-6923
AD  - Nuremberg Institute of Technology, 90489 Nurnberg, Germany.
FAU - Hennemann, Lukas
AU  - Hennemann L
AD  - Nuremberg Institute of Technology, 90489 Nurnberg, Germany.
FAU - Krauss, Hannes
AU  - Krauss H
AD  - Nuremberg Institute of Technology, 90489 Nurnberg, Germany.
FAU - Nitschke, Janina
AU  - Nitschke J
AD  - Nuremberg Institute of Technology, 90489 Nurnberg, Germany.
FAU - Renner, Philipp
AU  - Renner P
AD  - Nuremberg Institute of Technology, 90489 Nurnberg, Germany.
FAU - Niebler, Christine
AU  - Niebler C
AD  - Nuremberg Institute of Technology, 90489 Nurnberg, Germany.
FAU - Koelpin, Alexander
AU  - Koelpin A
AUID- ORCID: 0000-0002-9071-5661
AD  - Institute of High-Frequency Technology, Hamburg University of Technology, 21073 
      Hamburg, Germany.
LA  - eng
GR  - 13FH546IX6/Bundesministerium fur Bildung und Forschung/
PT  - Journal Article
DEP - 20210423
PL  - Switzerland
TA  - Sensors (Basel)
JT  - Sensors (Basel, Switzerland)
JID - 101204366
SB  - IM
MH  - Humans
MH  - Infant, Newborn
MH  - Microwaves
MH  - Monitoring, Physiologic
MH  - *Radar
MH  - Respiration
MH  - *Respiratory Rate
MH  - Signal Processing, Computer-Assisted
PMC - PMC8122919
OTO - NOTNLM
OT  - neonates
OT  - non-contact monitoring
OT  - respiratory rate
OT  - synchronous evaluation
COIS- The authors declare no conflict of interest.
EDAT- 2021/05/01 06:00
MHDA- 2021/05/04 06:00
PMCR- 2021/04/23
CRDT- 2021/04/30 01:22
PHST- 2021/02/25 00:00 [received]
PHST- 2021/04/18 00:00 [revised]
PHST- 2021/04/19 00:00 [accepted]
PHST- 2021/04/30 01:22 [entrez]
PHST- 2021/05/01 06:00 [pubmed]
PHST- 2021/05/04 06:00 [medline]
PHST- 2021/04/23 00:00 [pmc-release]
AID - s21092959 [pii]
AID - sensors-21-02959 [pii]
AID - 10.3390/s21092959 [doi]
PST - epublish
SO  - Sensors (Basel). 2021 Apr 23;21(9):2959. doi: 10.3390/s21092959.