Measurement of Dielectric Properties of Thin Materials for Radomes Using Waveguide Cavities
Abstract
:1. Introduction
2. Theory and Materials
3. Results
3.1. Simulated Results
3.2. Measurement Setup
3.2.1. Material Preparation
3.2.2. Network Analyzer Setup
- Connect waveguide adapters to the empty cavity with shims on either side;
- Save resonant peak data for the empty cavity;
- Disconnect adapters from the cavity;
- Place foam blocks within the cavity;
- Reconnect shims and adapters;
- Save resonant peak data for the cavity filled with foam;
- Disconnect adapters from the cavity;
- Remove foam blocks from the cavity;
- Place the sample within foam blocks;
- Carefully place foam blocks and the sample within the cavity;
- Reconnect adapters to the cavity;
- Save resonant peak data for the cavity filled with foam and the sample material;
- Repeat steps 9 to 12 for each material sample.
3.2.3. Collecting Data
3.3. Measured Results
3.4. Measurement Factors
4. Conclusions
Author Contributions
Funding
Data Availability Statement
Conflicts of Interest
References
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Measurement Method | Material Types | Assumed Mode |
---|---|---|
Transmission/reflection line | Coaxial line, waveguides | Fundamental |
Open-ended coaxial probe | Liquids, biological specimen, semi-solids | TEM, TE |
Resonant cavity | High temperatures, large/flat solids, gas, hot liquids | TM, TE |
Free-space | Rod-shaped solids, waveguides, liquids | TEM |
Material Name | Simple Name | Thickness (mm) |
---|---|---|
PTFE Coated Glass Fabric * [26] | PTFE Fabric | 0.15 |
Dyneema composite fabric hybrid * [27] | Dyneema | 0.1 |
Polyester, PU-Coated, impregnated, flame retardant, 240 g/sqm [25] | Polyester | 0.19 |
Ecopak EPX70 RS, Ripstop, recycling-backpack-laminate, 171 g/sqm [25] | Ecopak | 0.15 |
Etaproof 200, waterproof cotton, 200 g/sqm, 2nd Choice [25] | Etaproof | 0.27 |
Cordura, 500 den, coated [25] | Cordura | 0.36 |
N-Shell, z-liner pocket lining, 70 g/sqm [25] | N-Shell | 0.3 |
3-layer-laminate, robust, mini-ripstop, 170 g/sqm [25] | 3-LL | 0.3 |
2-layer-laminate, soft, slightly elastic, 105 g/sqm [25] | 2-LL | 0.2 |
Material | Features | ||||
---|---|---|---|---|---|
Flame-Retardant | Waterproof | Windproof | Abrasion Resistant | Inelastic | |
PTFE Fabric * | |||||
Dyneema * | |||||
Polyester | |||||
Ecopak | |||||
Etaproof | |||||
Cordura | |||||
N-Shell | |||||
3-LL | |||||
2-LL |
WR650 (Length = 105 mm) | |||||||
---|---|---|---|---|---|---|---|
Mode | Frequency (GHz) | Mode | Frequency (GHz) | Mode | Frequency (GHz) | Mode | Frequency (GHz) |
TE101 | 1.69 | TE323 | 6.25 | TE306 | 8.99 | TE328 | 12.30 |
TE102 | 3.00 | TM323 | 6.25 | TE525 | 9.21 | TM328 | 12.30 |
TE301 | 3.08 | TE503 | 6.25 | TE126 | 9.35 | TE508 | 12.30 |
TE302 | 3.95 | TE304 | 6.33 | TM126 | 9.35 | TE528 | 12.82 |
TE121 | 4.01 | TE522 | 6.48 | TE326 | 9.70 | TE109 | 12.89 |
TM121 | 4.01 | TE124 | 6.83 | TM326 | 9.70 | TE309 | 13.14 |
TE103 | 4.38 | TM124 | 6.83 | TE506 | 9.70 | TE129 | 13.39 |
TE122 | 4.71 | TE105 | 7.20 | TE107 | 10.04 | TM129 | 13.39 |
TM122 | 4.71 | TE523 | 7.23 | TE526 | 10.36 | TE329 | 13.64 |
TE321 | 4.76 | TE324 | 7.30 | TE307 | 10.36 | TM329 | 13.64 |
TM321 | 4.76 | TM324 | 7.30 | TE127 | 10.68 | TE509 | 13.64 |
TE501 | 4.76 | TE504 | 7.30 | TM127 | 10.68 | TE529 | 14.11 |
TE303 | 5.08 | TE305 | 7.65 | TE327 | 10.98 | TE1010 | 14.31 |
TE322 | 5.37 | TE125 | 8.07 | TM327 | 10.98 | TE3010 | 14.54 |
TM322 | 5.37 | TM125 | 8.07 | TE507 | 10.98 | TE1210 | 14.77 |
TE502 | 5.37 | TE524 | 8.15 | TE108 | 11.46 | TM1210 | 14.77 |
TE123 | 5.69 | TE325 | 8.47 | TE527 | 11.57 | TE3210 | 14.99 |
TM123 | 5.69 | TM325 | 8.47 | TE308 | 11.75 | TM3210 | 14.99 |
TE104 | 5.79 | TE505 | 8.47 | TE128 | 12.03 | TE5010 | 14.99 |
TE521 | 5.99 | TE106 | 8.62 | TM128 | 12.03 | TE5210 | 15.42 |
WR137 (Length = 127 mm) | |||||||
---|---|---|---|---|---|---|---|
Mode | Frequency (GHz) | Mode | Frequency (GHz) | Mode | Frequency (GHz) | Mode | Frequency (GHz) |
TE101 | 4.46 | TE121 | 19.50 | TE129 | 22.18 | TM326 | 24.03 |
TE102 | 4.91 | TM121 | 19.50 | TM129 | 22.18 | TE327 | 24.41 |
TE103 | 5.58 | TE122 | 19.61 | TE505 | 22.32 | TM327 | 24.41 |
TE104 | 6.39 | TM122 | 19.61 | TE506 | 22.66 | TE5010 | 24.55 |
TE105 | 7.31 | TE123 | 19.79 | TE1210 | 22.77 | TE328 | 24.83 |
TE106 | 8.29 | TM123 | 19.79 | TM1210 | 22.77 | TM328 | 24.83 |
TE107 | 9.32 | TE124 | 20.03 | TE321 | 22.99 | TE329 | 25.30 |
TE108 | 10.38 | TM124 | 20.03 | TM321 | 22.99 | TM329 | 25.30 |
TE109 | 11.47 | TE125 | 20.35 | TE507 | 23.05 | TE3210 | 25.82 |
TE1010 | 12.57 | TM125 | 20.35 | TE322 | 23.08 | TM3210 | 25.82 |
TE301 | 12.97 | TE126 | 20.72 | TM322 | 23.08 | TE521 | 28.72 |
TE302 | 13.13 | TM126 | 20.72 | TE323 | 23.23 | TE522 | 28.80 |
TE303 | 13.39 | TE127 | 21.15 | TM323 | 23.23 | TE523 | 28.92 |
TE304 | 13.75 | TM127 | 21.15 | TE324 | 23.44 | TE524 | 29.09 |
TE305 | 14.20 | TE501 | 21.55 | TM324 | 23.44 | TE525 | 29.30 |
TE306 | 14.73 | TE128 | 21.64 | TE508 | 23.50 | TE526 | 29.56 |
TE307 | 15.33 | TM128 | 21.64 | TE325 | 23.71 | TE527 | 29.87 |
TE308 | 16.00 | TE502 | 21.65 | TM325 | 23.71 | TE528 | 30.21 |
TE309 | 16.73 | TE503 | 21.81 | TE509 | 24.00 | TE529 | 30.60 |
TE3010 | 17.50 | TE504 | 22.03 | TE326 | 24.03 | TE5210 | 31.03 |
Simulated Permittivity | Simulated Loss Tangent | Calculated Permittivity | Calculated Loss Tangent | Permittivity Error (%) | Loss Tangent Error (%) |
---|---|---|---|---|---|
1.5 | 0.1 | 1.4964 | 0.1142 | 0.24 | 14.2 |
0.05 | 1.4888 | 0.0538 | 0.75 | 7.6 | |
0.01 | 1.492 | 0.0106 | 0.53 | 6 | |
0.005 | 1.4929 | 0.0051 | 0.47 | 2 | |
0.001 | 1.4945 | 0.0011 | 0.37 | 10 | |
2.2 | 0.1 | 2.195 | 0.1144 | 0.23 | 14.4 |
0.05 | 2.1944 | 0.0515 | 0.25 | 3 | |
0.01 | 2.195 | 0.0101 | 0.23 | 1 | |
0.005 | 2.1944 | 0.0061 | 0.25 | 22 | |
0.001 | 2.1966 | 0.0011 | 0.15 | 10 | |
2.9 | 0.1 | 2.8888 | 0.1232 | 0.39 | 23.2 |
0.05 | 2.9084 | 0.0589 | 0.29 | 17.8 | |
0.01 | 2.8982 | 0.0111 | 0.06 | 11 | |
0.005 | 2.9035 | 0.0057 | 0.12 | 14 | |
0.001 | 2.9027 | 0.0011 | 0.09 | 10 |
Simulated Permittivity | Simulated Loss Tangent | Calculated Permittivity | Calculated Loss Tangent | Permittivity Error (%) | Loss Tangent Error (%) |
---|---|---|---|---|---|
1.5 | 0.1 | 1.4768 | 0.1216 | 1.55 | 21.6 |
0.05 | 1.4884 | 0.0549 | 0.77 | 9.8 | |
0.01 | 1.4942 | 0.0113 | 0.39 | 13 | |
0.005 | 1.4926 | 0.0054 | 0.49 | 8 | |
0.001 | 1.4926 | 0.0008 | 0.49 | 20 | |
2.2 | 0.1 | 2.1794 | 0.1110 | 0.94 | 11 |
0.05 | 2.1806 | 0.0544 | 0.88 | 8.8 | |
0.01 | 2.1832 | 0.0117 | 0.76 | 17 | |
0.005 | 2.1832 | 0.0048 | 0.76 | 4 | |
0.001 | 2.2105 | 0.00103 | 0.48 | 3 | |
2.9 | 0.1 | 2.8546 | 0.1129 | 1.57 | 12.9 |
0.05 | 2.8482 | 0.0535 | 1.79 | 7 | |
0.01 | 2.8514 | 0.0126 | 1.68 | 26 | |
0.005 | 2.8482 | 0.0054 | 1.79 | 8 | |
0.001 | 2.8449 | 0.0009 | 1.90 | 10 |
Material | Thickness (m) | WR650 (Length = 105 mm) TE101 (fc = 1.65 GHz) | WR137 (Length = 127 mm) TE103 = (fc = 5.575 GHz) | ||||
---|---|---|---|---|---|---|---|
Permittivity | Loss Tangent | Noise (K) | Permittivity | Loss Tangent | Noise (K) | ||
PTFE Fabric * | 0.00015 | 2.9 | 0.0009 | 0.0024 | 2.87 | 0.0044 | 0.0392 |
Dyneema * | 0.0001 | 2.6 | 0.0019 | 0.0032 | 2.58 | 0.0135 | 0.0760 |
N-Shell | 0.0003 | 1.4 | 0.0064 | 0.0236 | 1.4 | 0.0094 | 0.1169 |
3-LL | 0.0003 | 2.09 | 0.0225 | 0.1012 | 1.98 | 0.0244 | 0.3608 |
2-LL | 0.0002 | 1.87 | 0.0208 | 0.0590 | 1.85 | 0.0267 | 0.2545 |
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Share and Cite
Dahms, T.; Hayman, D.B.; Mohamadzade, B.; Smith, S.L. Measurement of Dielectric Properties of Thin Materials for Radomes Using Waveguide Cavities. Telecom 2024, 5, 706-722. https://doi.org/10.3390/telecom5030035
Dahms T, Hayman DB, Mohamadzade B, Smith SL. Measurement of Dielectric Properties of Thin Materials for Radomes Using Waveguide Cavities. Telecom. 2024; 5(3):706-722. https://doi.org/10.3390/telecom5030035
Chicago/Turabian StyleDahms, Tayla, Douglas B. Hayman, Bahare Mohamadzade, and Stephanie L. Smith. 2024. "Measurement of Dielectric Properties of Thin Materials for Radomes Using Waveguide Cavities" Telecom 5, no. 3: 706-722. https://doi.org/10.3390/telecom5030035