International Journal of Mechanical Engineering and Technology (IJMET) Volume 9, Issue 13, December 2018, pp. 935 941, Article ID: IJMET_09_13_098 Available online at http://www.iaeme.com/ijmet/issues.asp?jtype=ijmet&vtype=9&itype=13 ISSN Print: 0976-6340 and ISSN Online: 0976-6359 IAEME Publication Scopus Indexed DESIGN OF MICROSTRIP RECTANGULAR PATCH ANTENNA FOR CANCER DETECTION B Nataraj and K R Prabha Department of Electronics and Communication Engineering, Sri Ramakrishna Engineering College, Coimbatore, Tamil Nadu, India ABSTRACT The aim of this paper is to design a rectangular microstrip patch antenna for cancer detection using microwave imaging method. The detection of cancer cells can be done with X-ray mammography, magnetic resonance imaging and ultrasound scanning. These methods have some drawbacks and are overcome by the microwave imaging technique. In this paper, the design of a microstrip rectangular patch antenna is proposed with the resonant frequency of 6.4GHz. The proposed patch antenna consists of RT-Duroid substrate of dielectric constant 2.2 of 2mm thickness. The parameters such as gain, S-parameters, directivity and iciency are obtained from the designed patch antenna using Advanced Design System momentum. The return loss at 6.4Ghz is 10.958. Key words: microstrip, antenna, cancer, gain, directivity, return loss, iciency Cite this Article: B Nataraj and K R Prabha, Design of Microstrip Rectangular Patch Antenna for Cancer Detection, International Journal of Mechanical Engineering and Technology 9(13), 2018, pp. 935 941. http://www.iaeme.com/ijmet/issues.asp?jtype=ijmet&vtype=9&itype=13 1. INTRODUCTION Over the last few years, a significant growth of research involving the use of microwave imaging has been taking place. Among the many examples of ongoing research, the use of microwaves for breast cancer diagnostic imaging has seen an increase of interest [1]. At present, X-ray mammography and Magnetic Resonance Imaging (MRI) are the main imaging techniques for detection and evaluation of breast cancer. But they both have their own limitations, e.g. high percentage of miss detection, harmful because of ionizing radiations, high cost and lengthy procedures. Hence, these issues are causing the researchers to develop another approach for breast cancer detection [2]. This antenna has been used for cancer detection and become interesting to researchers. This system is based on the transmission of particular range of frequency of waves. The principle of this radar is transmitting a wave and then detecting the reflected waves response [3]. In the UWB system, an antenna plays a very important place and features of the transceiver chain. An antenna acts as both transmitting and receiving the wave. The patch is designed to radiate and receiving a signal carrying an information to be processed. The http://www.iaeme.com/ijmet/index.asp 935 editor@iaeme.com
B Nataraj and K R Prabha microstrip patch antennas is one of the most commonly used antennas in this type of applications. It has more advantages such as ease of fabrication, simple structure, easy integration with microwave integrated circuits. Geometric shape of a microstrip antenna comprises a radiating element on the layer of dielectric substrate and on the other side a ground plane, as shown in figure 1. There are several category of the microstrip patch antenna, can be cited some example the circular, a square radiating element, triangular, semicircular, but the most common is rectangular element [4,5]. The study and the design of rectangular patch antenna are presented in this paper. Figure 1 Rectangular Patch Antenna 2. FEEDING TECHNIQUES OF MICROSTRIP ANTENNA The feeding techniques of microstrip patch antenna are of different types. The transfer of power to the patch antenna is done without any contacts by means of electromagnetic coupling. The techniques involved for feeding are coaxial probe feeding, feeding technique with microstrip line and aperture or proximity coupling methods. The microstrip line feeding technique makes use of microstrip patch to which the conducting strip is connected directly to it. This technique has an advantage that the conducting element can be cut on same substrate. The conducting element width is less than the patch antenna as shown in figure 2. Figure 2 Microstrip line In coaxial probe feeding technique, shown in figure 3 makes use of coaxial connector. The core of the coaxial connector is connected to the patch antenna and the other conductor of coaxial connector is connected to the ground of the patch antenna. This has major drawbacks that it is difficult to design. The proximity coupled feeding technique has the input feed is between two substrate and the patch element is placed above the substrate, as shown in figure 4. http://www.iaeme.com/ijmet/index.asp 936 editor@iaeme.com
Design of Microstrip Rectangular Patch Antenna for Cancer Detection Figure 3 Coaxial probe feed Figure 4 Proximity coupled feed In aperture coupled feed, the radiating patch is kept between the microstrip feed line and the ground plane, which can be coupled using a slot. The slot is kept between the ground and the patch element. This changes are depends on length and width. This technique is used to improve the simulation result [5] [6]. Figure 5 Aperture coupled feed 3. DESIGN RECTANGULAR PATCH ANTENNA A rectangular microstrip antenna, conceived for cancer detecting application is operating at a frequency of 6.4 GHz. The proposed rectangular patch antenna has been designed using the RT-Duroid substrate with dielectric constant of 2.2 and with substrate thickness of 2 mm. The basic steps for the development of rectangular patch antenna (RPA) are: Step 1: The width w of the radiating RPA is computed using equation http://www.iaeme.com/ijmet/index.asp 937 editor@iaeme.com
B Nataraj and K R Prabha c W (1) r 1 2 f 0 2 where c is the velocity of light, ε r is dielectric constant of the substrate and f 0 is the resonant frequency of antenna. Step 2: Effective Dielectric constant of the RPA is determined as r 1 r 1 1 12 2 2 h W Step 3: For the resonant frequency, the ective length is given by (3) c L 2 f 0 Step 4: Extension length of the RPA is computed using 1 2 W ( 0.3)( 0.264) L 0.412h h W ( 0.258)( 0.8) h The length " L" of the RPA is calculated as L L 2 L (5) 4. LAYOUT OF THE RECTANGULAR PATCH ANTENNA The 2-dimensional physical geometry of the microstrip rectangular patch antenna is shown in figure 6, which has a great advantage of easy manufacturing. Rectangular antenna can be applied for applications in Ultra High Frequency ranging from 300MHz to 3GHz, because the size of antenna affects the wavelength at the resonant frequency. (2) (3) (4) Figure 6 Layout of the rectangular antenna The formulas given in the design of microstrip patch antenna are used to determine the length and width of the patch. The length and width of the patch is 15mm and 18mm. The feed line length is 5 mm and width is 3mm. The layout of the proposed rectangular patch antenna is simulated using Advanced Design System momentum. The rectangular patch antenna is designed for resonant frequency of 6.4 GHz and the layout is shown in Fig. 7. For our antenna design for cancer detection, the intention is to fit the value of reflection http://www.iaeme.com/ijmet/index.asp 938 editor@iaeme.com
Design of Microstrip Rectangular Patch Antenna for Cancer Detection coicient (S11) at the resonant frequency, the goal function is to make a value S11 at -10 db for a bandwidth between 5-8GHz. Figure 7 Layout model of the rectangular antenna using ADS 5. RESULTS AND DISCUSSIONS The simulation of rectangular patch antenna was made using Advanced Design System. The simulation results of the rectangular microstrip patch antenna shows that the return loss is acceptable comparing to the standard values which ranges between 5 to 8 GHz and the resonant frequency is 6.4 GHz and the return loss S 11 is -10.96 db. Figure 8 shows the return loss depends on the frequency of antennas. The obtained results indicate that the antenna has characteristics in the whole frequency band with a return loss is -10 db. The return loss at the range 5 to 8GHz is approximately 0.8 db. From the result, antenna is operating between 5 to 8 GHz. Range 1 indicates starting frequency and range 2 indicates the final range. Res frequency denotes the resonant frequency. Figure 9 shows the directivity and iciency of the radiating antenna which is approximately equal to the 6dB of the optimized rectangular patch. It is clear from the figure that the patch resonates at 6.4 GHz and has minimum loss at the resonant frequency of -10.96dB. The radiation pattern of rectangular microstrip antenna is depicted below in figure 10 & 11. One lobe (main lobe) corresponds to the theoretical radiation pattern of patch antenna radiant. Figure 8 Return loss of optimized antenna http://www.iaeme.com/ijmet/index.asp 939 editor@iaeme.com
B Nataraj and K R Prabha Figure 9 Return loss antenna simulation Figure 10 Radiation pattern front view Figure 11 3D radiation pattern opposite view Table I shows the simulation of directivity and gain of microstrip antenna with rectangular patch. Directivity, Gain and power radiated are important parameters to determine the iciently of antenna. Gain of 3.48 is achieved. http://www.iaeme.com/ijmet/index.asp 940 editor@iaeme.com
Design of Microstrip Rectangular Patch Antenna for Cancer Detection Table 1 Antenna Parameters Power radiated (Watts) 0.5150 Effective angle (degrees) 148.305 Directivity (db) 6.2820 Gain (db) 3.248 6. CONCLUSIONS The rectangular microstrip patch antenna was successfully designed for frequency that operates at 5 to 8 GHz frequencies using advanced design system. From observing the return loss, it is very clear that this antenna works on the designed frequency range with the required level for detection of cancer cells. This research can be extended to study various slot antennas in terms of resonant frequency and wide bandwidth for wireless communication applications. REFERENCES [1] Matteo Bassi, An Integrated Microwave Imaging Radar With Planar Antennas for Breast Cancer Detection, IEEE Transactions On Microwave Theory And Techniques, vol. 61, No. 5, 2013. [2] M. Arif Khan and M. Aziz Ul Haq, A Novel Antenna Array Design for Breast Cancer Detection School of Computing and Mathematics, IEEE Industrial Electronics and Applications Conference, IEACon 2016. [3] Yong-Xin Guo, Kah-Wee Khoo, Ling Chuen Ong, Wideband Circularly Polarized Patch Antenna Using Broadband Baluns", IEEE Transactions on Antennas and Propagation, vol. 56, issue 2, 2008. [4] A.H.M. ZahirulAlam, Md. Rafiqul Islam and Sheroz Khan, "Design and Analysis of UWB Rectangular Patch Antenna", Pacific conference on Applied Electromagnetics Proceedings, 2007. [5] Werfelli Houda, Mondher Chaoui, Hamadi Ghariani and Mongi Lahiani, "Design of a pulse generator for UWB communications", 10 th International Multi-Conferences on Systems Signals & Devices, 2013. [6] Mahdi Ali, Abdennacer Kachouri and Mounir Samet "Novel method for planar microstrip antenna matching impedance", Journal of Telecommunications, 2010. [7] S.Sivasundarapandian, C.D. Suriyakala "Novel Octagonal UWB Antenna for Cognitive Radio", IOSR Journal of Electronics and Communication Engineering, 2012. [8] Mustafa K. Taher Al-Nuaimi and William G. Whittow, "On the Miniaturization of Microstrip Line-Fed Slot Antenna Using Various Slots", IEEE Loughborough Antennas and Propagation Conference (LAPC), Loughborough, 2011. [9] Aruna Rani, R.K. Dawre, "Design and Analysis of Rectangular and U Slotted Patch for Satellite Communication", International Journal of Computer Applications, December 2010. [10] Dhivya N, Pooja Jayakumar, Prashanth Mohan, Rekha Zacharia, Vishnupriya Vasudevan, G. Prabha, "Comparative Study Of Slotted Microstrip Antenna Fed Via A Microstrip Feed Line", Proceedings of 1st IRF International Conference, Coimbatore, 9th March-2014. http://www.iaeme.com/ijmet/index.asp 941 editor@iaeme.com