Project Specification

Microstrip Patch Antenna

A microstrip patch antenna for detecting malignant breast tumors.

Specifications

Antennamicrostrip rectangular patch
Dimension100mm×100mm
Resonating frequency2.45GHz
SoftwareHFSS software
With tumor:
E field0.6282 A/m
H field49.4340 V/m
Return loss-22.4dB
VSWR1.164
SAR1.3870 W/Kg
Without tumor:
E field0.5081 A/m
H field46.8052 V/m
Return loss-22.4dB
VSWR1.164
SAR1.2694 W/Kg

Overview

Problem / Solution

Breast cancer affects the majority of women globally. It has been determined that the survival rate would be extremely low if it advanced to a later stage. Breast cancer has a poor chance of survivability because early identification is not possible. The survival percentage will rise to 98% if the illness is discovered early. Furthermore, there are several ways of detecting breast cancer, but they have drawbacks, including high costs, the need for ionization rays, and the fact that most of them catch the disease at an advanced stage. Therefore, it's critical to find breast cancer at an early stage.

Patients' chances of survival are improved with a microstrip patch antenna, which can identify tumors at an early stage. Additionally, it is claimed to be inexpensive, comfortable for women, and highly successful. Since it is simple to use, general physicians have relied on it as their main tumor detection method. Additionally, it can be used in remote locations without access to modern equipment. The parameters VSWR, Return loss, Specific Absorption Rate, Electric field, and Magnetic field from the antennas were examined to detect malignant tumors in the breast. It is created with HFSS software utilizing a microstrip rectangular patch at a resonant frequency of 2.45GHz.

Design

Utilizing HFSS software, the microstrip patch antenna design has a 100mm by 100mm dimension.

How does it work?

To locate malignant breast cancers, a microstrip patch antenna that can send electromagnetic waves toward the breast and be absorbed by the breast is used in the design. The amount of electromagnetic waves absorbed and reflected by the breast affects the identification of malignancies. It is also discovered that the rate at which electromagnetic waves are absorbed by breast tissue with and without a tumor varies. The visible difference will aid in determining whether or not the patient has a tumor. The antenna was designed in the study taking specific absorption rates into account (SAR). The SAR values of 1.2 W/Kg without tumor and 1.3 W/Kg with tumor are within the acceptable range. When a tumor is present, the SAR value rises. In essence, it says that the presence of a tumor results in greater dielectric characteristics. The tumor scatters a greater quantity of signal energy than the fabric of a breast that is healthy and tumor-free.

 

Results

Return Loss (s11 Parameter)

Bounce back reflection is also known as a return. The size of the reflection or echo is also determined by the return loss (s11 parameter). Also mentioned is the requirement that return loss is less than -10 dB. The return loss was -22.4 dB. According to the study's findings, there was no difference in return loss between those who had tumors and those who did not.

Voltage Standing Wave Ratio (VSWR)

The voltage standing wave ratio (VSWR), which represents the power reflected from the antenna, is thought to be a function of the reflection coefficient. It shows how well the antenna matches its impedance. Additionally, impedance matching needs to be high for efficient signal transmission and reception. The VSWR should be less than two, it is decided. VSWR for the planned antenna is 1.164.

Electric Field

Furthermore, the research indicated that the breast's maximal electric field is 46.8052 V/m. A breast with the presence of a tumor's maximal electric field was measured and found to be 49.4340 V/m. It was determined that there is a 2.6288 V/m difference.

Magnetic Field

The study found that the magnetic field in the breast is 0.5081 A/m. Meanwhile, the magnetic field in a breast with a tumor is 0.6282 A/m, greater than 0.1201 A/m.

SAR (Specific Absorption Rate)

The study stated that SAR is the amount of power absorbed by the medium per unit of mass. The standard that limits the maximum amount of power absorbed by the breast tissue during breast cancer detection is the specific absorption rate. Also, according to the FCC, a SAR level of 1.6 W/Kg is set in the US and India. The designed antenna has a SAR value of 1.2694 W/Kg without tumor and 1.3870 W/Kg with tumor. Further, the SAR value increases in the presence of a tumor.

References

Pranali Nilesh Ajnadkar, Mrinali Harish Amin

Wevolver 2022