*3.3.3 Reflection and transmission coefficient calculation*

The reflection coefficient and transmission coefficient with different frequencies are illustrated in **Figures 6** and **7**.

From the results which are illustrated in **Figures 6** and **7**, note that the reflection and transmission coefficients have a directional relationship with the frequency of a transmitted wave; and from **Figure 6**, note that the blood has the lowest reflection coefficients, which means the ultra-wideband pulses spend shorter time passing through the blood. Also, the transmission coefficient of skin-air is smaller than the transmission coefficient of air-skin, so improving the reflection and transmission coefficients increases the ability of the radar imaging process in any direction either from the inside to the outside transceiver or from the outside to the inside transceiver, as illustrated in **Figure 4**.

The radar can make the two processes together for getting a very clear image, which makes the new radar pass the problems of previous radars, which have been


### **Table 2.**

*Distance and time between the layers.*

From the results illustrated in **Figure 8**, the blood permittivity has been decreased gradually when the blood glucose concentration is increased, and the opposite is right, where the blood dielectric properties can be increased by decreasing the blood glucose concentration. Also, these results can be served to design a noninvasive ultra-wideband blood glucose concentration measurement device. The next experiment has been achieved by adding various normal saline intravenous nutrients' concentration for detecting its effects on the blood dielectric properties (especially the permittivity), where the using of the salinity concentrations from 0 to 2% is applied, and **Figure 9** shows the results. These results have been served to conclude that the blood permittivity will be decreased gradually when the blood salinity percentage, %, is increased, and the opposite is right, where the blood dielectric properties can be increased by decreasing the salinity percentage, %. Also, these results can be served to design a new ultra-wideband device used for detecting the blood salinity percentage noninvasively or for blood pressure measurements. The last experiment has been achieved by adding the anticoagulant material (citrate or EDTA) to the blood and then measuring its effects on the dielectric properties (permittivity), as illustrated in **Table 3**. From the results above, the adding of anticoagulant to the blood will cause an increase in the blood permittivity.

*Permittivity of blood Ԑ as function of glucose concentration.*

*Medical Application of Ultra-Wideband Technology DOI: http://dx.doi.org/10.5772/intechopen.93577*

**Figure 8.**

**Figure 9.**

**85**

*Permittivity of blood Ԑ as function of salinity concentration.*

### **Figure 6.**

*Relationship between reflection coefficients and frequency.*

**Figure 7.** *Relationship between transmission coefficients and frequency.*

represented by the power loss in the first layers and the receiving of weak power signals from the other depth layers, also enabling the choosing of the best way that has the lowest reflection coefficient and the highest transmission coefficient due to minimizing of the power dispersion [43].

#### *3.3.4 Experiment results*

The first experiment was done by adding the glucose water intravenous nutrient with different concentrations to detect its effects on the dielectric properties of blood (especially on the permittivity), where we will use the glucose concentrations from 70 to 16,000 mg/dL, and **Figure 8** shows the results.

## *Medical Application of Ultra-Wideband Technology DOI: http://dx.doi.org/10.5772/intechopen.93577*

#### **Figure 8.**

*Permittivity of blood Ԑ as function of glucose concentration.*

From the results illustrated in **Figure 8**, the blood permittivity has been decreased gradually when the blood glucose concentration is increased, and the opposite is right, where the blood dielectric properties can be increased by decreasing the blood glucose concentration. Also, these results can be served to design a noninvasive ultra-wideband blood glucose concentration measurement device.

The next experiment has been achieved by adding various normal saline intravenous nutrients' concentration for detecting its effects on the blood dielectric properties (especially the permittivity), where the using of the salinity concentrations from 0 to 2% is applied, and **Figure 9** shows the results. These results have been served to conclude that the blood permittivity will be decreased gradually when the blood salinity percentage, %, is increased, and the opposite is right, where the blood dielectric properties can be increased by decreasing the salinity percentage, %. Also, these results can be served to design a new ultra-wideband device used for detecting the blood salinity percentage noninvasively or for blood pressure measurements.

The last experiment has been achieved by adding the anticoagulant material (citrate or EDTA) to the blood and then measuring its effects on the dielectric properties (permittivity), as illustrated in **Table 3**. From the results above, the adding of anticoagulant to the blood will cause an increase in the blood permittivity.

**Figure 9.** *Permittivity of blood Ԑ as function of salinity concentration.*

represented by the power loss in the first layers and the receiving of weak power signals from the other depth layers, also enabling the choosing of the best way that has the lowest reflection coefficient and the highest transmission coefficient due to

The first experiment was done by adding the glucose water intravenous nutrient

with different concentrations to detect its effects on the dielectric properties of blood (especially on the permittivity), where we will use the glucose concentrations

from 70 to 16,000 mg/dL, and **Figure 8** shows the results.

minimizing of the power dispersion [43].

*Relationship between transmission coefficients and frequency.*

*Relationship between reflection coefficients and frequency.*

*Innovations in Ultra-WideBand Technologies*

*3.3.4 Experiment results*

**Figure 6.**

**Figure 7.**

**84**


the depth of human tissues, and minimizing the time of arrival (TOA), where the ultra-wideband pulses have been received on the other side where there is no need to pass through human tissue again (one-way). The new radar has been designed to cancel the position calculations of return points, and it just needs to calculate the position of the received antenna on the other side by calculating the total offset (It) which is shown in **Figure 4**. As well as the ability of the new radar, for imaging in both directions (selective direction), makes it avoid the old problems of previous radars with power losses and image collapsing. Also, this new radar can be developed to work with other internal imaging devices like endoscopes and with the alike principle of work and similar design in addition to the study of the ability of improving the radar imaging by injecting the patient's body with a certain substance that manipulates the blood dielectric properties. The finding of the transmission coefficient and reflection coefficient among the multilayer tissue enables the new radar for choosing the best way to the imaging, which has been determined

*Medical Application of Ultra-Wideband Technology DOI: http://dx.doi.org/10.5772/intechopen.93577*

depending on the dielectric properties of tissues under exam. If the ultra-wideband pulses are transmitted from a layer with higher dielectric properties to the next layer with lower dielectric properties, then the reflection coefficient has a negative amplitude and the transmission coefficient has a high positive amplitude according to Eqs. (18) and (19), which will be due to most of the ultra-wideband pulses passing the boundary between the layers and arriving to the next layer, and the little percentage of pulses will be reflected from the boundary and will return in the opposite direction of propagation, and the opposite is right. The experiment results in Section 3.3.4 can introduce additional features that can be used for improving the ultra-wideband imaging through adjusting of the dielectric properties of blood by controlling the reflection and transmission coefficients in accord with the radar requirements. And as mentioned in the above paragraph, if the radar sends pulses from the outer transceiver into the inner one (one-way image), then the transmission coefficient must be improved, while if the radar sends pulses from the outer to another transceiver that is also outside the body (two-way image), then the reflection coefficient must be improved. Finally, the blood dielectric properties can help us to find the glucose concentration noninvasively by using one ultra-wideband transceiver (antenna), depending on the comparison between the transmitted and reflected pulses. The UWB antenna will be attached to the superficial blood vessel to avoid the noise and power attenuation from another human tissue to increase the accuracy of readings (where, the using of two antennas to send and receive the pulses from the other side of the hand will result in the wave being passed through many layers, and the power of the signal will be absorbed, which will cause

**Relationship Notes**

Glucose concentration α T1*<sup>=</sup>*<sup>2</sup> By considering the blood is 2nd medium Glucose concentration α T1*<sup>=</sup>*<sup>2</sup> By considering the blood is 2nd medium

By considering the blood is 2nd medium

By consider the blood is 2nd medium

ε

Γ1*=*<sup>2</sup>

T1*<sup>=</sup>*<sup>2</sup>

Glucose concentration α <sup>1</sup>

Anticoagulant material α Ԑ Anticoagulant material α <sup>1</sup>

Anticoagulant material α <sup>1</sup>

Blood temperature α Ԑ Hemoglobin percentage α Ԑ

*A summary of relationships.*

**Table 4.**

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**Table 3.** *Anticoagulant effect.*

Note that all experiments have been practiced in the 5 GHz frequency center, with its fitting to the FCC mask, at accepted SAR level, at 37°C temperature, and with fresh blood, and with fresh blood (+O blood group). Also, in the real case, the experiment has some limitations in the adding of these materials to the patients' blood (effected by the patient's condition and his disease background).
