In vitro detection of skin cancer using anUWBstacked micro strip patch antenna with microwave imaging

Abstract

The inherent advantages of microwave imagining (MWI) being noninvasive and nonionizing for cancer detection, has attracted the attention of researchers in this area. Therefore, the present research article proposes an UWB (ultrawideband) stacked MSA (Micro-strip antenna) for MWI of skin cancer. The proposed research work precisely focuses on the diagnosis of skin cancer in human forearm using the designed MSA in mono-static radar based configuration to collect S parameter data and process it to form an image of the scanned body area. The proposed UWB SAMPA (stacked aperture coupled micro-strip patch antenna) has three layered stacked aperture coupled geometry with a defected ground structure with dimensions 36 Â 30 Â 4.85 mm 3 . A simulated and measured bandwidth of 6.23 GHz (6.14 to 12.37 GHz) and 5.28 GHz (5.72 to 11 GHz) are observed and a gain of 6.3 and 6.4 dB is reported respectively.The in vitro detection of skin cancer is done by fabricating a bio mimic of human forearm with same electrical properties as that of human skin. The proposed SAMPA is used to collect S parameter data from the scan of forearm phantom. This data is then processed in beamforming algorithms to create a 2D dielectric profile of the scanned forearm area. The multiply Delay and Sum with Coherent factor (CF-DMAS) beam forming algorithm is utilized for reconstruction of the 2D image of the cancerous effected area along with its locations and size in MATLAB. The proposed MWI procedure is validated experimentally with the prototype of proposed SAMPA and a human forearm phantom after simulations in CST MWS. The proposed SAMPA is also safe for the human exposure, as it has simulated specific absorption rate (SAR) on the forearm phantom of 1.013 and 1.09 at frequency 7.04 and 8.67 GHz respectively. K E Y W O R D Smicrowave imaging, multiply delay and sum with coherent factor, skin cancer, stacked aperture coupled micro strip antenna

In silico, in vitro, and in vivo validation of a microwave imaging system using a low‐profile Ultra Wide Band Archimedean spiral antenna to detect skin cancer

“…The MI process employs the designed ASMA near the bio‐phantom of the human forearm to detect the cancer‐affected areas inside it. However, to ensure human‐exposure safety during this procedure, it is necessary to maintain a SAR value below or equal to 1.6 W/Kg per 1 g of tissue 5,6 . The values of the SAR for the aforementioned purpose can be calculated using Equation () for 1 mW of power and are given as: Here, ρ = volume density, σ = conductivity of the bio‐phantom, and E = electric field that is incident on the bio‐phantom.…”

“…Figure 6C illustrates the graph of normalized SAR at a frequency of 7.3 GHz with respect to the distance (on the z‐axis) within the bio‐phantom. This data is utilized to determine the penetration depth (PD), defined as 37% of the maximum SAR value 6 . Figure 6C shows that the PD of the radiation inside the bio‐phantom is approximately 8 mm.…”

“…Beamforming algorithms are a better alternative than inverse‐scattering problems that perform spatial filtering on the recorded data acquired from MSRMI to create the 2D map of energy from the different focused points. The existing beamforming algorithms for image reconstruction are mainly Delay Multiply and Sum (DMAS) and Delay and Sum (DAS) 6,24 . Thus, this subsection compares the quality of images (on the basis of tumor location, SMR, and SCR 6,8 ) that are reconstructed using DAS and advanced DMAS (CF‐DMAS) beamforming algorithms.…”

“…The proposed ASMA uses a mono‐static technique, considered simpler and easier to implement compared to multi‐static radar‐based MI approaches present in the literature 30,31 . The study also focuses on reconstructing tumor images (superficial/skin cancer detection) using different algorithms, compared to the cited works 6,13,32 . The microwave imaging methodology proposed using ASMA as a sensor surpasses cited approaches in detecting superficial/skin cancer due to its distinct features, including the UWB response, its simple and compact design, and its validation through both in vitro and in vivo studies.…”

“…30,31 The study also focuses on reconstructing tumor images (superficial/skin cancer detection) using different algorithms, compared to the cited works. 6,13,32 The T A B L E 5 Quality matrix of the reconstructed image using different beamforming algorithms. In-vitro and in-vivo validations to reconstruct the image microwave imaging methodology proposed using ASMA as a sensor surpasses cited approaches in detecting superficial/skin cancer due to its distinct features, including the UWB response, its simple and compact design, and its validation through both in vitro and in vivo studies.…”