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RF Test - human tissue equivalent

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m.charge

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Looking to have an advice to select the material that is equal to the human body dielectric , I tried one of the goop phantom that we have from a long time ago (not make sure what is the material) but there is a huge difference when I tried to tune the antenna with phantom vs. human body.
 

jiripolivka

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Looking to have an advice to select the material that is equal to the human body dielectric , I tried one of the goop phantom that we have from a long time ago (not make sure what is the material) but there is a huge difference when I tried to tune the antenna with phantom vs. human body.

My experience is similar. Human tissue can be modeled but not easily replaced by a close material. Some researchers use pork meat, but a dead tissue is completely different at RF from a living tissue. Many researchers use saline water bags, often include plastic pipes with water flow simulating blood circulation.
To tune an antenna you can try someone's thighs, at least a real living tissue :))
 

E Kafeman

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There are standards for the dielectric and conductive properties such as for measuring SAR with a phantom head (Sam) filled with a liquid.

Typical ingredients (wt %)
900 MHz sugar: 57.90, water: 40.30, cellulose: 0.24, NaCl: 1.38, Bactericide:0.18
1800 MHz water: 55.41, DGBE: 44.51, NaCl: 0.08
1900 MHz same as 1800 but no NaCl

Amount of sugar requires boiling water to solve.
DGBE can harm some plastics as it is a kind of ethanol, use good containers. Not fun to find 10 liters of sirup dripping on other RF equipment.
There are also other recipes for hand/torso/full body models.
If you not want to mix it yourself: https://www.speag.com/products/dasy/tissue-simulating-liquids-gels-and-solids/

These recipes have been discussed as they are designed for skinny models and designed very long ago and average people are fatter today.
RF in fat differentiates a lot compared to meat, bone and common body fluids.
RF for medical implants need to in more detail take account what kind of tissue that is in absolute nearfield. Tables exist.
Many RF modelling softwares have predefined detailed body models.
 
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Eng.Wad

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Have you first done with simulated results? did you use voxel data, phantoms? you have to consider which part of the body you want to test your antenna with.. you can find body tissue properties in the official website of FCC in case you want to build your phantom in your software
 

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