Modeling of the Test Fixtures to Improve the HBC Channel ... · Presentation Outline • Human Body...
Transcript of Modeling of the Test Fixtures to Improve the HBC Channel ... · Presentation Outline • Human Body...
![Page 1: Modeling of the Test Fixtures to Improve the HBC Channel ... · Presentation Outline • Human Body Communication - HBC • HBC Channel modeling Primary channel model • HBC Channel](https://reader035.fdocuments.net/reader035/viewer/2022071214/604257ed47eca0052b4fc357/html5/thumbnails/1.jpg)
Modeling of the Test Fixtures to Improve the HBC Channel Interpretation
M. D. Pereira, G. A. Alvarez, F. R. de Sousa Radiofrequency Research Group
![Page 2: Modeling of the Test Fixtures to Improve the HBC Channel ... · Presentation Outline • Human Body Communication - HBC • HBC Channel modeling Primary channel model • HBC Channel](https://reader035.fdocuments.net/reader035/viewer/2022071214/604257ed47eca0052b4fc357/html5/thumbnails/2.jpg)
Presentation Outline
• Human Body Communication - HBC
• HBC Channel modeling� Primary channel model
• HBC Channel measurements� Measurement system and results
• Test Fixture modeling� Extended Model
• Final Considerations
2
![Page 3: Modeling of the Test Fixtures to Improve the HBC Channel ... · Presentation Outline • Human Body Communication - HBC • HBC Channel modeling Primary channel model • HBC Channel](https://reader035.fdocuments.net/reader035/viewer/2022071214/604257ed47eca0052b4fc357/html5/thumbnails/3.jpg)
Presentation Outline
• Human Body Communication - HBC
• HBC Channel modeling� Primary channel model
• HBC Channel measurements� Measurement system and results
• Test Fixture modeling� Extended Model
• Final Considerations
3
![Page 4: Modeling of the Test Fixtures to Improve the HBC Channel ... · Presentation Outline • Human Body Communication - HBC • HBC Channel modeling Primary channel model • HBC Channel](https://reader035.fdocuments.net/reader035/viewer/2022071214/604257ed47eca0052b4fc357/html5/thumbnails/4.jpg)
HBC – Human body communication
4
• PAN/HBC/IBC/BCC - Thomas G. Zimmerman [Zimmerman, 1995].
• Electrostatic coupling to the body using electrodes (galvanic e capacitive).
Zimmerman, T. G., “Personal Area Networks: Near-field intra-body communication,”
M.S. Thesis, MIT Media Laboratory, Cambridge, MA, Sept. 1995.
![Page 5: Modeling of the Test Fixtures to Improve the HBC Channel ... · Presentation Outline • Human Body Communication - HBC • HBC Channel modeling Primary channel model • HBC Channel](https://reader035.fdocuments.net/reader035/viewer/2022071214/604257ed47eca0052b4fc357/html5/thumbnails/5.jpg)
HBC – Human body communication• PAN/HBC/IBC/BCC - Thomas G. Zimmerman [Zimmerman, 1995].
• Electrostatic coupling to the body using electrodes (galvanic e capacitive).
• Low frequency operation (<100 MHz).
• Advantages over other BAN options:
� Higher data security.
� Higher coexistence.
� Lower channel attenuation.
� Lower power consumption.
5
Zimmerman, T. G., “Personal Area Networks: Near-field intra-body communication,”
M.S. Thesis, MIT Media Laboratory, Cambridge, MA, Sept. 1995.
![Page 6: Modeling of the Test Fixtures to Improve the HBC Channel ... · Presentation Outline • Human Body Communication - HBC • HBC Channel modeling Primary channel model • HBC Channel](https://reader035.fdocuments.net/reader035/viewer/2022071214/604257ed47eca0052b4fc357/html5/thumbnails/6.jpg)
Capacitive HBC characterization and modeling• Required for link budget analysis (Tx output power, Rx sensitivity,
operating frequency).
• Literature review:
� Different author find different attenuation levels and frequency profile.
� Most models cannot fully reproduce the measured channel frequency profiled.
� Obtained models are not complete or where not validate correctly.
� Correct channel path is not preserved.
� Neglecting of the influence of test fixture.
6
![Page 7: Modeling of the Test Fixtures to Improve the HBC Channel ... · Presentation Outline • Human Body Communication - HBC • HBC Channel modeling Primary channel model • HBC Channel](https://reader035.fdocuments.net/reader035/viewer/2022071214/604257ed47eca0052b4fc357/html5/thumbnails/7.jpg)
Presentation Outline
• Human Body Communication - HBC
• HBC Channel modeling� Primary channel model
• HBC Channel measurements� Measurement system and results
• Test Fixture model� Extended Model
• Final Considerations
7
![Page 8: Modeling of the Test Fixtures to Improve the HBC Channel ... · Presentation Outline • Human Body Communication - HBC • HBC Channel modeling Primary channel model • HBC Channel](https://reader035.fdocuments.net/reader035/viewer/2022071214/604257ed47eca0052b4fc357/html5/thumbnails/8.jpg)
Primary channel
• Primary channel partitioning:
� Intrinsic channel.
� Extrinsic channel.
� Secondary channel: external structures (environment and test fixture).
8
![Page 9: Modeling of the Test Fixtures to Improve the HBC Channel ... · Presentation Outline • Human Body Communication - HBC • HBC Channel modeling Primary channel model • HBC Channel](https://reader035.fdocuments.net/reader035/viewer/2022071214/604257ed47eca0052b4fc357/html5/thumbnails/9.jpg)
Intrinsic channel• Network based on unit blocks equivalent circuit offers good
compact alternative [Xu et al, 2011].
9
R. Xu; H. Zhu; J. Yuan, "Electric-Field Intrabody Communication Channel Modeling With
Finite-Element Method," Biomedical Engineering, IEEE Transactions on, March 2011
![Page 10: Modeling of the Test Fixtures to Improve the HBC Channel ... · Presentation Outline • Human Body Communication - HBC • HBC Channel modeling Primary channel model • HBC Channel](https://reader035.fdocuments.net/reader035/viewer/2022071214/604257ed47eca0052b4fc357/html5/thumbnails/10.jpg)
10-1
100
101
102
103
0
2
4
6
h [cm]
Cre
t [p
F]
L = 2 cm, Emp. Ex.
L = 2 cm, FEM
100
101
102
103
0
0.05
0.1
d [cm]
Cx [
pF
]
L = 2 cm, FEM
Extrinsic channel
• Return capacitances: empirical exp. and 3D EM simulations EM 3D.
10
![Page 11: Modeling of the Test Fixtures to Improve the HBC Channel ... · Presentation Outline • Human Body Communication - HBC • HBC Channel modeling Primary channel model • HBC Channel](https://reader035.fdocuments.net/reader035/viewer/2022071214/604257ed47eca0052b4fc357/html5/thumbnails/11.jpg)
Extrinsic channel• Body leakage capacitances.
• Inter-electrode and electrode skin impedances.
11
![Page 12: Modeling of the Test Fixtures to Improve the HBC Channel ... · Presentation Outline • Human Body Communication - HBC • HBC Channel modeling Primary channel model • HBC Channel](https://reader035.fdocuments.net/reader035/viewer/2022071214/604257ed47eca0052b4fc357/html5/thumbnails/12.jpg)
Primary channel
12
![Page 13: Modeling of the Test Fixtures to Improve the HBC Channel ... · Presentation Outline • Human Body Communication - HBC • HBC Channel modeling Primary channel model • HBC Channel](https://reader035.fdocuments.net/reader035/viewer/2022071214/604257ed47eca0052b4fc357/html5/thumbnails/13.jpg)
106
107
108
-100
-90
-80
-70
-60
-50
-40
f [Hz]
Gai
n [
dB
]
d = 20 cm
d = 30 cm
d = 140 cm
Primary channel model
• High pass profile.
• Low frequency dependence on distance.
• Attenuation levels between 50-100 dB.
13
![Page 14: Modeling of the Test Fixtures to Improve the HBC Channel ... · Presentation Outline • Human Body Communication - HBC • HBC Channel modeling Primary channel model • HBC Channel](https://reader035.fdocuments.net/reader035/viewer/2022071214/604257ed47eca0052b4fc357/html5/thumbnails/14.jpg)
Presentation Outline
• Human Body Communication - HBC
• HBC Channel modeling� Primary channel model
• HBC Channel measurements� Measurement system and results
• Test Fixture modeling� Extended Model
• Final Considerations
14
![Page 15: Modeling of the Test Fixtures to Improve the HBC Channel ... · Presentation Outline • Human Body Communication - HBC • HBC Channel modeling Primary channel model • HBC Channel](https://reader035.fdocuments.net/reader035/viewer/2022071214/604257ed47eca0052b4fc357/html5/thumbnails/15.jpg)
Measurement system
• R&S ZVB VNA.
• Baluns FTB-1-1.
• Cables RG 316.
• 2 x 2 cm2 electrodes.
• SOLT calibration at the balun’s transitions.
15
Body
![Page 16: Modeling of the Test Fixtures to Improve the HBC Channel ... · Presentation Outline • Human Body Communication - HBC • HBC Channel modeling Primary channel model • HBC Channel](https://reader035.fdocuments.net/reader035/viewer/2022071214/604257ed47eca0052b4fc357/html5/thumbnails/16.jpg)
106
107
108
-60
-50
-40
-30
-20
-10
f [Hz]
Gai
n [
dB
]
d = 15 cm
d = 30 cm
d = 140 cm
Channel measurements
• Pass band profille.
• Independence of d in lower frequencies.
• Attenuation levels between 10-50 dB.
16
![Page 17: Modeling of the Test Fixtures to Improve the HBC Channel ... · Presentation Outline • Human Body Communication - HBC • HBC Channel modeling Primary channel model • HBC Channel](https://reader035.fdocuments.net/reader035/viewer/2022071214/604257ed47eca0052b4fc357/html5/thumbnails/17.jpg)
Measurements and model comparison
• 30 cm propagation distance.
• Differences on freq. profile.
• Over 45 dB higher attenuation.
• Balun’s effect [Sakai et al, 2013].
17
106
107
108
-100
-90
-80
-70
-60
-50
-40
-30
-20
-10
0
f [Hz]
Gai
n [
dB
]
30 cm
Measurement
Primary channel model
Sakai, J.; Lin-Sheng Wu; Hu-Cheng Sun; Yong-Xin Guo, "Balun's effect on the measurement of transmission characteristics
for intrabody communication channel," Microwave Workshop Series on RF and Wireless Technologies for Biomedical and
Healthcare Applications (IMWS-BIO), 2013 IEEE MTT-S International , vol., no., pp.1,3, 9-11 Dec. 2013.
![Page 18: Modeling of the Test Fixtures to Improve the HBC Channel ... · Presentation Outline • Human Body Communication - HBC • HBC Channel modeling Primary channel model • HBC Channel](https://reader035.fdocuments.net/reader035/viewer/2022071214/604257ed47eca0052b4fc357/html5/thumbnails/18.jpg)
Presentation Outline
• Human Body Communication - HBC
• HBC Channel modeling� Primary channel model
• HBC Channel measurements� Measurement system and results
• Test Fixture modeling� Extended Model
• Final Considerations
18
![Page 19: Modeling of the Test Fixtures to Improve the HBC Channel ... · Presentation Outline • Human Body Communication - HBC • HBC Channel modeling Primary channel model • HBC Channel](https://reader035.fdocuments.net/reader035/viewer/2022071214/604257ed47eca0052b4fc357/html5/thumbnails/19.jpg)
Test fixture modeling
• DUT and test fixture transitions.• Modifified cables transitions model.
• Baluns: model extraction.
19
![Page 20: Modeling of the Test Fixtures to Improve the HBC Channel ... · Presentation Outline • Human Body Communication - HBC • HBC Channel modeling Primary channel model • HBC Channel](https://reader035.fdocuments.net/reader035/viewer/2022071214/604257ed47eca0052b4fc357/html5/thumbnails/20.jpg)
Extended model
20
![Page 21: Modeling of the Test Fixtures to Improve the HBC Channel ... · Presentation Outline • Human Body Communication - HBC • HBC Channel modeling Primary channel model • HBC Channel](https://reader035.fdocuments.net/reader035/viewer/2022071214/604257ed47eca0052b4fc357/html5/thumbnails/21.jpg)
106
107
108
-100
-90
-80
-70
-60
-50
-40
-30
-20
-10
0
f [Hz]
Gai
n [
dB
]
d = 20 cm
d = 30 cm
d = 140 cm
Extended Model
Primary Model
Extended model
21
• Reproduces the band pass profile.
• Low frequency independence of d.
• Around 45 dB lower attenuation.
![Page 22: Modeling of the Test Fixtures to Improve the HBC Channel ... · Presentation Outline • Human Body Communication - HBC • HBC Channel modeling Primary channel model • HBC Channel](https://reader035.fdocuments.net/reader035/viewer/2022071214/604257ed47eca0052b4fc357/html5/thumbnails/22.jpg)
106
107
108
-100
-90
-80
-70
-60
-50
-40
-30
-20
-10
0
f [Hz]
Gai
n [
dB
]
Primary channel model
Extended model
Measurements data
Measurements and Extended model comparison
22
• Good extended model fit below 70 MHz
• Differences < 5.5 dB.
![Page 23: Modeling of the Test Fixtures to Improve the HBC Channel ... · Presentation Outline • Human Body Communication - HBC • HBC Channel modeling Primary channel model • HBC Channel](https://reader035.fdocuments.net/reader035/viewer/2022071214/604257ed47eca0052b4fc357/html5/thumbnails/23.jpg)
Presentation Outline
• Human Body Communication - HBC
• HBC Channel modeling� Primary channel model
• HBC Channel measurements� Measurement system and results
• Test Fixture modeling� Extended Model
• Final Considerations
23
![Page 24: Modeling of the Test Fixtures to Improve the HBC Channel ... · Presentation Outline • Human Body Communication - HBC • HBC Channel modeling Primary channel model • HBC Channel](https://reader035.fdocuments.net/reader035/viewer/2022071214/604257ed47eca0052b4fc357/html5/thumbnails/24.jpg)
Final Considerations
• Contributions:
� Proposal of a systematic primary channel partitioning that facilitates HBC understanding and modeling.
� Proposal of extended model that includes the test fixture.
� Verification of test fixture influences.
� Validation of primary channel model and identification of challenges for transceiver design.
• Ongoing studies:
� Methodology to de-embed the test fixture from measurements.
24
![Page 25: Modeling of the Test Fixtures to Improve the HBC Channel ... · Presentation Outline • Human Body Communication - HBC • HBC Channel modeling Primary channel model • HBC Channel](https://reader035.fdocuments.net/reader035/viewer/2022071214/604257ed47eca0052b4fc357/html5/thumbnails/25.jpg)
Thank You