Simplified Human Body Models for Interference Analysis in the Cognitive Radio for Medical Body Area Networks

Transcription

1 Simplified Human Body Models for Interference Analysis in the Cognitive Radio for Medical Body Area Networks Łukasz Januszkiewicz Lodz University of Technology, Institute of Electronics, Poland

2 Outline: Motivation Human Body Models Simplified body model Interference scenario for CR in WBAN Computer simulations Conclusions 14/04/2014 Simplified Human Body Models for Interference Analysis in the Cognitive Radio 2

3 Motivation for the resarch on human body models Measurements and simulation of: Wearable antenna Wireless Body Area Network Wearable wireless sensors 14/04/2014 Simplified Human Body Models for Interference Analysis in the Cognitive Radio 3

4 Human Body Models Numerical heterogeneous models Represent human body tissues which are sampled to allow finite difference / finite elements calculation Differ with number of tissues and size of elementary cell Remcom NMR Hershey CST HUGO Virtual Population 14/04/2014 Simplified Human Body Models for Interference Analysis in the Cognitive Radio 4

5 Human Body Models Homogenous models used for measurements The shape of body is preserved Tissues are simulated with a liquid SAM Specific Anthropomorphic Mannequin 14/04/2014 Simplified Human Body Models for Interference Analysis in the Cognitive Radio 5

6 Simplified body model Goals Simple physical model that can be easily manufactured (geometry and materials which make it easily to reproduce) Comparable values of simulated radio signal attenuation and antenna radiation pattern with heterogeneous model 14/04/2014 Simplified Human Body Models for Interference Analysis in the Cognitive Radio 6

7 Simplified body model The simplified model consist of cylinders. Dimensions approximate NMR Hershey model with 6 standard PVC pipes Model geometry optimized with XFdtd PCV pipes filled with tissue-simulant liquid 14/04/2014 Simplified Human Body Models for Interference Analysis in the Cognitive Radio 7

8 Simplified body model Simplified model was verified by measurements of wearable antenna radiation pattern in 2.4 GHz band 14/04/2014 Simplified Human Body Models for Interference Analysis in the Cognitive Radio 8

9 Medical Body Area Networks The MWBAN structure:* Intra- Wireless Body Area Network (Intra-WBAN) Inter- Wireless Body Area Network (Inter-WBAN). *Chavez-Santiago, R.; Nolan, K.E.; Holland, O.; De Nardis, L.; Ferro, J.M.; Barroca, N.; Borges, L.M.; Velez, F.J.; Goncalves, V.; Balasingham, I., "Cognitive radio for medical body area networks using ultra wideband, Wireless Communications, IEEE, vol.19, no.4, pp.74,81, August /04/2014 Simplified Human Body Models for Interference Analysis in the Cognitive Radio 9

10 Interference scenario for CR in WBAN Cognitive radio in Intra-WBAN, radio channel affected by radio wave attenuation in the body 14/04/2014 Simplified Human Body Models for Interference Analysis in the Cognitive Radio 10

11 Interference scenario for CR in WBAN Cognitive radio in Inter-WBAN, radio channel affected by on-body antenna radiation pattern 14/04/2014 Simplified Human Body Models for Interference Analysis in the Cognitive Radio 11

12 Computer simulations UWB antenna model used for simulations 14/04/2014 Simplified Human Body Models for Interference Analysis in the Cognitive Radio 12

13 The results of the model validation for Intra-WBAN Signal attenuation between transmitter located on the front of the torso and the receiver located on the back 14/04/2014 Simplified Human Body Models for Interference Analysis in the Cognitive Radio 13

14 The results of the model validation for Intra-WBAN Signal attenuation between transmitter located on the front of the torso and the receiver located on the left arm 14/04/2014 Simplified Human Body Models for Interference Analysis in the Cognitive Radio 14

15 The results of the model validation for Intra-WBAN Signal attenuation between transmitter located on the right arm and the receiver located on the left arm 14/04/2014 Simplified Human Body Models for Interference Analysis in the Cognitive Radio 15

16 The results of the model validation for Inter-WBAN On-body antenna radiation pattern simulated with NMR Hershey model and simplified model 900 MHz 1500 MHz 14/04/2014 Simplified Human Body Models for Interference Analysis in the Cognitive Radio 16

17 The results of the model validation for Inter-WBAN On-body antenna radiation pattern simulated with NMR Hershey model and simplified model 2500 MHz 5000 MHz 14/04/2014 Simplified Human Body Models for Interference Analysis in the Cognitive Radio 17

18 The results of the model validation for Inter-WBAN On-body antenna radiation pattern simulated with NMR Hershey model and simplified model 7500 MHz 14/04/2014 Simplified Human Body Models for Interference Analysis in the Cognitive Radio 18

19 Conclusions Results obtained with the simplified and the reference model are similar for Intra-WBAN case. The signal attenuation simulated for the high attenuation case shows good agreement in several sub-bands (2000MHz 3000MHz, 4000MHz 5500MHz) In case when different antenna locations are used the results obtained with simplified and reference model are in good agreement. 14/04/2014 Simplified Human Body Models for Interference Analysis in the Cognitive Radio 19

20 Conclusions The simplified model gives very similar results to the reference model for Inter-WBAN simulations. The radiation patterns of UWB antenna located on the body obtained with those models do not differ much in the frequency range from 900 MHz to 7500 MHz. The proposed simplified phantom can be suitable for further experimental investigation and testing of CR wireless body area networks. 14/04/2014 Simplified Human Body Models for Interference Analysis in the Cognitive Radio 20

21 Thank you. 14/04/2014 Simplified Human Body Models for Interference Analysis in the Cognitive Radio 21