Design and Development of Microstsrip Patch Antenna for Detection of Breast Cancer

Abstract

The utility of ultra wideband technology in the field of wireless communication systems has attained much attention in recent years due to its inherent advantages of large bandwidth, low power consumption and high speed short distance data transmissions. UWB antennas can be used for the detection of tumors and cancer using Radar based Microwave Imaging technique. Here the same antenna is made to transmit to an affected area and receive back from the same area. Based upon the difference between the received reflected signals from the normal and malignant breast tissues, tumors can be detected. Therefore, this thesis documents the development and analysis of four microstrip patch antennas with an overall aim to achieve ultra wideband (3.1GHz to 10.6GHz) and miniaturization characteristics using different patch geometries and defected ground structure. The first antenna geometry presented here consists of a staircase shaped slotted patch antenna with a reduced DGS which operates in the frequency band from 3.11GHz to 12.93GHz with bandwidth of 9.82GHz. The second antenna geometry is an extended semicircular microstrip patch antenna with a reduced DGS which covers the frequency range from 3.09GHz to 9.7GHz with bandwidth of 6.61GHz. The third antenna geometry is a fork shaped microstrip patch antenna with a reduced DGS which covers an operational band from 3.71GHz to 11.48GHz with bandwidth of 7.77GHz. The fourth antenna geometry is a stub loaded rectangular microstrip patch antenna with a reduced DGS which occupies the frequency band from 0.17GHz to 7.25GHz with bandwidth of 7.08GHz. A generalized parametric study of various antenna design parameters is executed to investigate the antenna performance and achieve optimum results. All UWB antennas are designed and simulated using CST MWS’14. To validate the simulated results for practical applications, prototype of antennas is fabricated using photolithography process and tested experimentally tested using a VNA. The UWB fork shaped and rectangular microstrip fed patch antennas provides acceptable gains and can be used for breast cancer detection using mono-static radar based microwave imaging. A 3D planar breast phantom is modeled and simulations are carried out for by varying the distance between the breast phantom surface and UWB antenna for tumor radius of 10mm. It is observed that the reflected signals from an affected area show a lesser return loss for the same band as compared to the one without a tumor. This is because tumors have more water content and show more reflections. Therefore, the proposed UWB antennas can be successfully employed for the detection of breast cancer and tumors.