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In this article, we propose to combine the powers of two magnetrons. By combining the power of a microwave, two continuous magnetrons waves are used as the source of the s-band waves. We use square waveguides (WR340) the Y-structure to achieve industrial high power at 2.45 GHz. To combine the power ofa 1 kW magnetron and use it to adjust the phase difference of the two magnetrons. With low loss for using two magnetrons in the process, insertion loss is less than 0.5 dB, reflection loss is less than -28 dB at 2.45 GHz frequency.

This paper presents a high-frequency dielectric applicator for ripening fruit. In this study, we demonstrate with the electric field applicator is designed with two plates at 2450 MHz and gets power at 120 W (MUEGGE MR1000D) to generate power into the material. Simulation results show that the power loss density. This dielectric property was tested by using bananas as an example for the experiment. The conditions for the experiment were divided into four cases as follows: dielectric material a) without electric field, b) under the electric field for 3 minutes, c) under the electric field for 5 minutes, and d) under the electric field for 10 minutes. The dielectric properties of bananas are not stable, depending on the power absorbed at that time. In exceptional, condition (a) has a number of dielectric properties different from other conditions. The electric field will affect to reduce the dielectric constant. Results of dielectric properties was measured by open-ended coaxial dielectric probe kit (N1501A, Keysight Technology) connected to a vector network analyzer (E5071C, Keysight Technology) that can be operated in the range of 0.5–10 GHz. The results of physical material was measured using NIR hyperspectral imaging (Specim FX17e) following formats: RGB Image, and PCA Model 2D contour.

This paper presents a high-frequency dielectric heating system for breast cancer treatment. The power loss density (W/m 3) was investigated with a curved plate applicator by 3D simulation. The dielectric constant and loss factor of tumor tissue provides 55.25 and 19.8, respectively. This dielectric heating system was implemented based on the high power signal generator 2450 MHz, which is designed by a series resonance circuit with an LC matching element. The dielectric properties of breast phantom and tumor tissue were performing by open-ended coaxial dielectric probe kit connected to a vector network analyzer that can be operated in the range of 1-10 GHz. The impedance matching was measured in breast phantom as a surrogate tumor tissue with an applicator. The heat distribution on tumor tissue was measured using IR cameras. The parameters of microwave DC input power 180 W, efficiency about 30%, and get power at 60 W (47.82 dBm) to generate a stabilized temperature between $39-4 2^{\circ}\mathrm{C}$ .

This paper presents an experimental study of exterminate worm by high frequency using dielectric heating. The aim of this paper is study worm affected by high frequency radiation. For the experiments exterminate worm, throughout these experiments, we have chosen to use G. mellonella larva and Tenebrio molitor as worm. The effect of high frequency radiation, temperature at any distance, time of radiation are investigated. The result show at skin depth 2–3 cm at 90 second for radiation both of species not died immediately and at skin depth at 4 cm temperature not high enough to exterminate them.

This peper present about design of system for pest control in grain storage with high frequency. This experiment study effect of pest on high frequency radiation and experiment for using high frequency to pests controlled in storage grains. Experiment were conducted on two room to compare the changes in rice weight caused by the effects of pests between the two rooms, first room was pest controlled with high frequency, second room was not pest controlled to make the environment like a normal warehouse, in these experiments Using Sitotroga cerealella as grain moth, the weight of grains at any distances from the antenna are investigated. The results show weight of grains between two room are different, Room with pest controlled by high frequency had a lower rate of grains weight reduction than other rooms, in last month for experiment the weight of grains from room was pest controlled with high frequency is 990 g, while weight of grains from the room was not pest controlled is 874 g.

[EN] High-frequency magnetic field has been developed pervasively. The induction of heat from the magnetic field can help to treat tumor tissue to a certain extent. Normally, treatment by the low-frequency magnetic field needed to be combined with magnetic substances. To assist in the induction of magnetic fields and reduce flux leakage. However, there are studies that have found that high frequencies can cause heat to tumor tissue. In this paper present, a new magnetic application will focus on the analysis of the high-frequency magnetic nickel core with multi-coil. In order to focus the heat energy using a high-frequency magnetic field into the tumor tissue. The magnetic coil was excited by 915 MHz signal and the combination of tissues used are muscle, bone, and tumor. The magnetic power on the heating predicted by the analytical model, the power loss density (2.98e-6 w/m3) was analyzed using the CST microwave studio., This work was supported by Suranaree University of Technology (SUT) and by the Office of the Higher Education under NRU project of Thailand

In this paper presents the improvement of electric field focusing by using microwave dielectric heating techniques with curved plate applicator for deep hyperthermia in breast cancer treatment. To focus on the deep heat distribution in the breast phantom close to the cancer cells, the electric loss density was analyzed in the cancer cells at different location inside of the breast phantom. This heating technique was implemented based on the electric field using the electrode plate applicator was excited by 2.45 GHz. The cancer cells position in breast phantom was located at different location in xy-plane and xz-plane. Simulation results show that the heating efficiency area can be relocated and deep focused when the rotation axis of curved plate has been rotated in the vertical or horizontal direction of breast phantom and also have describe that the heat distribution area to the affected neighboring tissues has been decreased. The maximum heating area was close to the cancer cells at the midpoint position between electrode plates. The CST microwave studio is used for simulation.

This paper present experimental results of the prototype insect pest control system that use Laterally Diffused MOSFET (LDMOS) as active device in solid-state power amplifier (SSPA) for better efficiency dielectric heating. Nowadays, SSPA were known as the most efficiency device for radio frequency (RF) amplifier. Recently, insect pest control has been moving from chemical fumigation to dielectric heating technique because the chemical that use for insect pest control are affect the environments and they could remain as food residue might affect health in long term. Generally, using high voltage in megahertz range, electric tube (or vacuum tube) can be done for this task. However, the tube, is suffer from low efficiency that might be bad in long term because of electricity bill. The results of using the prototype SSPA pest control system in rice weevil pest control 1000 Watts DC in. 64% overall efficiency was obtained. Cost of the treatment process is US$ 0.00147/kg. The advantage of high efficiency in dielectric heating not only for insect pest control but also could apply to any related applications that use dielectric heating.

In this paper an experiment and optimization of magnetostrictive transducer for long time operation to find maximum amplitude of vibration and thermal limit. This vibration helps dissolution limestone in the oil pipeline transportation. To solve the problem of magnetostrictive transducers breaking or crack from overheating by the decomposition of limestone in the oil pipeline transportation. It is a technique to finding suitable frequency, duty cycle and the appropriate range of amplitude and thermal that not causing of overheat in magnetostrictive transducers. In the experimental and results, it is found that the magnetostrictive transducers will be operated in suitable frequency 11 kHz at duty cycle 45% at amplitude 1240 mv and temperature at magnetostrictive transducer 82.5 °C, respectively. The advantage of the experimental results is that the system can be operated at appropriate amplitude and reasonable temperature without any failure.

This paper is focused on an experiment about the output load of heating induction during heat exchange. Reference was taken from the experiment of Keeratidech Thepsatitsilp and his further research found out the appropriate forms for output load have multilayer metallic hollow cylinder can make the outermost layer have more heat than the other layers next to it. These other layers are not commonly hot as observed during this experiment. The supply pattern in the experiment on output load reveals that the outermost layer will hot most. We used materials like zinc alike and pattern of output load and they look very similar to the original model. The results of the experiment found out the outermost load layer will be the hottest and the heat will decrease respectively when getting to the next layers. Also the dimensions width and space of opening on the slide in output load will produce heat which will also affects the inner layer.

This article presents new current-mode quadrature oscillator circuits using OTA which are designed from block diagram. The proposed circuits consist of three OTAs and two grounded capacitors. The circuits have high output impedance appropriate for cascade connection application in current mode technique which is capable to directly drive load. The oscillators use only grounded capacitor which is very appropriate for further development into an integrated circuit. In addition, the condition of oscillation can be adjusted orthogonally from the frequency of oscillation. The results of PSPICE simulation program are corresponding to the theoretical analysis.

This article presents new current-mode oscillator circuits using CDTAs which is designed from block diagram. The proposed circuits consist of three CDTAs and two grounded capacitors. The condition of oscillation can be adjusted electronically/orthogonally from the oscillation frequency by adjusting bias current of the CDTAs. The proposed quadrature oscillators have high output impedance and use only grounded capacitors without any external resistor which is very appropriate for future development into an integrated circuit. The PSPICE simulation and experimental results are corresponding to the theoretical analysis.

This paper experiment and design about output load of induction heating for use in air heat exchanger application. By using various structure of output that have a wide area for exchange heat between air and solid such as, multilayer metallic hollow cylinder, multilayer in different height metallic hollow cylinder and multiple metallic tube by using the same type of material to experiment for find which structure have a good characteristic and suitable with air heat exchanger. We found a problem that multilayer metallic hollow cylinder, multilayer in different height metallic hollow cylinder is not suitable with air heat exchanger and we still found that multiple metallic tube have a good characteristic to use in air heat exchanger application.

An analysis and design of dielectric heating system by using radio frequency electric field (RFEF) will be presented for the milk pasteurization process. It is a technique to transmit the electric fields into the intermediary by using the RFEF. To determine heat distribution in the dielectric loads, which electric field intensity are analyzed to be suitable for fluid and milk. In heating process, the heated material must be the polar molecules to perform the best efflciency of electric fleld transmission into the medium in order to increase the temperature of medium to greater heights. The electric fleld distributions on the lossy medium was analyzed using the CST EM STUDIO program. To investigate the difference of electric power on heating predicted by the theoretical model. In order to verify the simulation results. The proposed system is realized and experimentally examined. The applicator of RFEF with excited by 40 MHz signal and electric fleld strength of 1.6 kV/cm. In the results, it is found that the temperature of milk would be increased about 72.3°C, the process will be take approximately 2 minutes, and reduced population of bacteria 109,260 cfu/ml. Moreover, the investigation result revealed that the temperature of 71.7°C, it will be eliminated the bacteria in milk and extended shelf life of milk. The advantage of the principle of radio frequency electric flelds is that it can be applied to eliminate the bacteria in milk pasteurization.

This paper presents an optimal design of strip folded dipole antenna with a stacking technique to stabilize the resonance frequency. The designed double-layer strip folded dipole antenna worked well with the cylindrically curved surface on the human body. While being bent, the antenna will change the extended length in each layer within the stacking flexible copper-clad laminate. In this case, the properties of the antenna will be automatically adjusted. However, the extended length can occur at the contact point in each layer. So, we can choose between two points and four points by selecting different types of the designs. This reason, the performance of the extended length can be added by two and four when being compared to the previous multilayer design and the total layer of the new antenna was only two. The extended length of the antenna resulted in making antenna resonance frequency improvement become more stable. The contribution of proposed antenna was used only two layers of flexible copper-clad laminate that reduces a number of antenna's layers with a folded dipole antenna, which causes the designed less complicated, and the flexibility is advantageous for WBAN applications. The double-layer strip folded dipole antenna is designed for 2.45GHz WBAN application.

This paper demonstrates a design of double-layer copper sheet suitable for RFID tags antenna called extended double-layer flexible strip dipole antenna. RFID tag antenna is widely used with different surfaces. The result found that RFID tag antenna can be bended or curved responding to the cylinder shape of the objects. Our proposed extended double-layer flexible strip dipole antenna has been technically designed to make changes on itself to obtain the result in increasing resonance frequency when it is being bended. The key concept of the study is the designed antenna which can freely change inside each layer when applying itself on curved object. The result of this design reveals that antenna has better performance than modern antenna. The extended double-layer flexible strip dipole antenna for RFID tags was designed for resonance frequency of 2.45 GHz. Consequently, the analysis of antennas efficiency will be affected by thickness. The designed antenna there will be considered and discussed to find out the relative value in order to use creating the design for the antenna that is suitable for the further study.

This article presents current-mode universal biquad filters based on CDTAs. The filter circuits using four CDTAs and two grounded capacitors which are able to provide low-pass, high-pass, band-pass, band-reject and all-pass functions. The pole frequency can be orthogonally controlled from quality factor and the circuits have high output impedance appropriate for cascade connection application in current mode which is capable to directly drive load. This qualification is very appropriate for further development into an integrated circuit. The results of PSPICE simulation program are corresponding to the theoretical analysis.

The design of curved patch array antenna for small missile application is presented. A thin copper plate antenna was attached a part of plastic pipe. This antenna is designed on cylinder metal object for such an application in military communication devices and antenna analysis was conducted by using the CST program. The frequency of a designed antenna was adjusted at 2.4 GHz. The proposed antenna is realized and experimentally examined, since it is small size, light weight, easy method fabrication and low manufacturing cost. In measurement, it is found that the propose antenna have the return loss was lower than-10 dB which covered frequency range 2.3 GHz-2.7 GHz. The average gain achieved in the propose antenna is about 6.13 dB over the operating frequency. The advantage of the proposed antenna is that it can be used to small missile for military application.

This paper presents the optimization of dielectric heating by using capacitor copper plate material. It has dimension of 50x50 mm. and the distance between plates is 3 mm. This work is used for preheating of insect and pests. Considering the RLC resonance circuit and the power per heating area, the rice weevils are used for sample dielectric. While the power transfer is varied from 10 - 80 watt and resonance frequency at 65 MHz for analysis, the rice weevils are died when the power transfer are more than 70 watt in 1 second. Moreover, It the power transfer is decrease, the period of time is increase. Approximate 10 watt of power transfer, the plate copper has less power so the rice weevils are breaking. Therefore, the power transfer has an effect on the heating area, which is the relation of the fast time.

This article presents a current-mode quadrature oscillator. The proposed oscillator can provide 2 sinusoidal output currents with 90 0 phase difference. It also provides high output impedances that make the circuit able to directly drive load without additional current buffer. The condition of oscillation and frequency of oscillation can be controlled independently and electronically by adjusting the bias currents of the CCTAs. The circuit uses 3 current controlled transconductance amplifiers (CCTAs) and 2 grounded capacitors. The proposed circuit uses only grounded capacitors without additional external resistors, the proposed circuit is considerably appropriate to further developing into an integrated circuit. The results of PSPICE simulation program are corresponding to the theoretical analysis. 

This study presents the resistorless floating inductance simulator circuit based on employing voltage differencing buffered amplifier (VDBA) as new active component. The proposed floating inductance simulator circuit uses two VDBAs and only one grounded capacitor, which is suitable for integrated circuit design. The resulting equivalent inductance value of the proposed simulator can be tuned electronically through the transconductance parameter of the VDBA. As application example, the second-order RLC bandpass filter has been simulated using the proposed tunable floating inductance simulator. The simulation results using standard 0.35 μm BiCMOS process model are included to verify the theoretical analysis.

This paper presents the impedance improvement technique by stacking a flexible copper-clad laminate. The designed Multilayer Strip Dipole antenna worked well with curved objects like cylindrical. While curving on an object, antenna lengths will change a relative length in each layer within stacking flexible copper-clad laminate. Curving of the designed antenna extended length of each layer within the antenna, and then affected an impedance of antenna to be automatically adjustable. At the mean time, an extended length of the antenna resulted in antena's impedance improvement to become more stable for frequency response. The Multilayer Strip Dipole antenna is designed for Thailand UHF RFID applications that operate on 920 MHz.

This research is conducted to analyze the efficiency of dielectric heating by increasing the input ports which are to be symmetrically model on the electrode plate. This analysis is considering of the electric field distribution and intensity in dielectric loads. The electric fields are caused by the electric power on electrode plates of the input ports to improve the thermals temperatures and electric field distribution of dielectric loads. The dielectric loads are the grains and pests, the rice and rice weevils are the target dielectric materials. To investigate the heating predicted by the theoretical model, the electric field distribution and intensity are analyzed by using the finite difference time domain method. The results demonstrate that the efficiency of the dielectric heating exterminated pests and temperature of grains without losing the quality. The advantage of the method is being able to be utilized for the dielectric heating applications to pest control and control the appropriate temperature of the grains in the future.

This paper presents breast cancer detection by observing the specific absorption rate (SAR) intensity for identification tumor location, the tumor is identified in coordinates (x,y,z) system. We examined the frequency between 4-8 GHz to look for the most appropriate frequency. Results are simulated in frequency 4-8 GHz, the model overview include normal breast with 50 mm radian, 5 mm diameter of tumor, and ultra wideband (UWB) bowtie antenna. The models are created and simulated in CST Microwave Studio. For this simulation, we changed antenna to 5 location around the breast, the tumor can be detected when an antenna is close to the tumor location, which the coordinate of maximum SAR is approximated the tumor location. For reliable, we experiment by random tumor location to 3 position in the same size of tumor and simulation the result again by varying the antenna position in 5 position again, and it also detectable the tumor position from the antenna that nearby tumor position by maximum value of SAR, which it can be detected the tumor with precision in all frequency between 4-8 GHz., {"references":["American Cancer Society, \"Breast Cancer Fact & Figures 2013-2014,\" 2013","M. Klemm, I. J. Craddock, J. A. Leendertz, A. Preece, and R. Benjamin, \"Radar-based breast cancer detection using a hemispherical antenna array—experimental results,\" IEEE Transactions on Antennas and Propagation, vol. 57, no.6 pp. 1692-1232, 2010.","P. M. Meaney, M. W. Fanning, T. Raynolds, C. J. Fox, Q. Fang, C. A. Kogel, S. P. Popalack, and K. D. Paulsen , \"Initial clinical experience with microwave breast imaging in women with normal mammography,\" Academic Radiol, vol. 14, pp. 207-218, 2007.","A. Christ, A. Klingenbock, T. Samaras, C. Goiceanu, and N. Kuster, \"The dependence of electromagnetic far-field absorption on body tissue composition in the frequency range from 300 MHz to 6 GHz,\" IEEE Transaction on Microwave Theory and Techniques, vol. 54 ,no. 5, pp. 2188-2195, 2006.","E. C. Fear, P. M. Meaney, and M. A. Stuchly, \"Microwaves for breast cancer detection?,\" IEEE Potentials, vol. 22, pp. 12-18, 2003.","P. Thosdee, \"Design of an antenna and RF front end transmitter circuit for ultra wideband wireless communication systems,\" Suranaree university of technology, 2008.","S. Thanormsuay, P. Thosdee, and C. Thongsopa, \"Array of quasi-rhomboid antenna for ultra wideband applications,\" ECTI-CON 2008, pp. 293-296, 2008.","N. S. Hassaine, L. Merad, S. M. Meriah, and F. T. Bendimerad, \"UWB bowtie slot antenna for breast cancer detection,\" World Academy of Science, Engineering and Technology, vol. 6, pp. 1218-1221, 2012.","A. Santorelli, \"Breast screening with custom-shaped pulsed microwaves (ch. 4),\"McGill University, 2012.\n[10]\tS. A. Winkler, E. Porter, A. Santorelli, M. Coates, and M. Popovic, \"Recent progreass in ultra-wideband microwave breast cancer detection,\" Ultra-wideband (ICUWB), pp. 182-186, 2012.\n[11]\tS. M. Razavizadeh, \"A new link set-up for breast tumor detection,\" Power Amplifiers for Wireless and Radio Applications (PAWR), pp. 109-111, 2013.\n[12]\tS. I. Al-Mously, and M. M. Abousetta, \"A study of the hand-hold impact on the EM interaction of a cellular handset and a human,\"World Academy of Science, Engineering and Technology, Vol. 2, pp. 157-161, 2008.\n[13]\tD. X. Yin, M. Li, and J. L. Li, \"Non-invasive breast cancer thermotherapy studies using conformal microstrip antennas,\" Antenna, Propagation & EM Theory (ISAPE),pp. 159-162, 2012."]}

The optimal power transmission of a flat spiral coils are presented for wireless power transfer applications. It is a technique to increase the power transmission efficiency of magnetic field for wireless power transfer system by applying a flat spiral coils in conjunction with ferrite materials. The magnetic field distribution of flat spiral ferrite core materials and flat spiral air core will be analyzed by using the CST EM STUDIO program. Theoretical analyses investigate that a novel flat spiral coil applicator is effective for radiating the magnetic field or increasing the power transmission efficiency of wireless power transfer system. In the simulations, we competitions the magnetic field radiation and longest distance between the two kinds of induction coils with ferrite core and air core. The results of the simulation showed that the flat spiral ferrite core material has increased the power transmission efficiency about 42% when compared to the flat spiral air core. The advantage of a flat spiral coils by using ferrite materials are presented is that it can be applied to wireless power transfer system to high effectively.

This paper presents the development and design of the curved rectangular patch arrays antenna for small missile application. This design uses a 0.1mm flexible copper sheet on the front layer and back layer, and a 1.8mm PVC substrate on a middle layer. The study used a small missile model with 122mm diameter size with speed 1.1 Mach and frequency range on ISM 2.4 GHz. The design of curved antenna can be installation on a cylindrical object like a missile. So, our proposed antenna design will have a small size, lightweight, low cost and simple structure. The antenna was design and analysis by a simulation result from CST microwave studio and confirmed with a measurement result from a prototype antenna. The proposed antenna has a bandwidth covering the frequency range 2.35-2.48 GHz, the return loss below -10 dB and antenna gain 6.5 dB. The proposed antenna can be applied with a small guided missile effectively., {"references":["","G. A. El-Sheikh, \"Performance investigation of a homing guided missile with positioning the seeker antenna,\" Proceedings of the Twenty-First National Radio Science Conference, pp. C20 - 1-10, 2004.","Cong Chen, Li Jiebo, Lin Zhang and Haitao Chen, \"Research of the missile and aircraft base mounted antennas for data transmission,\" International Conference on Microwave and Millimeter Wave Technology, pp. 392 – 394, 2010.","G. R. DeJean, T.T. Thai, S. Nikolaou and M.M. Tentzeris, \"Design and Analysis of Microstrip Bi-Yagi and Quad-Yagi Antenna Arrays for WLAN Applications,\" IEEE Antennas and Wireless Propagation Letters, vol. 6, pp. 244 – 248, 2007.","Lin Jinyong, Li Gang, Sun Shenghe, Zhu Wenbiao, Gao Xiaoying, \"Modeling Investigation in Large Scale System of Autonomous Formation Flying,\" Journal of System Simulation, Vol.19, No.16, pp. 3631-3633, August 2007.","G. R. DeJean and M. M. Tentzeris, \"A new high-gain microstrip Yagi array antenna with a high front-to-back (F/B) ratio for WLAN and millimeter-wave applications,\" IEEE Trans. Antennas Propag., vol. 55, pp.298–304, Feb. 2007.","B. Yu, D. Wu and K. Seo, \"Array of waveguide-fed microstrip antennas,\" International Conference on Communication Systems, pp. 797 - 800, 2008.","A. Sabban, \"Applications of MM Wave Microstrip Antenna Arrays,\" International Symposium on Systems and Electronics, pp. 119 – 122, 2007.","\"CST-Microwave Studio,\" ed, (2009).","Kumar, G. and Ray, K.P., Broadband Microstrip Antennas, Artech House, Inc, 2003.\n[10] Balanis, C.A., Advanced Engineering Electromagnetics, John Wiley & Sons, New York, 1989\n[11] Garg, R., Bhartia, P., Bahl, I., Ittipiboon, A., Microstrip Antenna Design Handbook, Artech House, Inc, 2001.\n\n "]}

In this paper, the effect of cylindrical shield to heating area and location of induction heating for breast cancer hyperthermia treatment with hyperthermia inductive heating are presented. To determine heat distribution in the breast, which electric loss density is analyzed for various aperture sizes and radius of shielded cylindrical. It is a technique to control magnetic field intensity and relocate the heating area by using a cylindrical metal shielding with aperture. In the simulation, the inductive applicator is a ferrite core with diameter of 7 cm and excited by 4 MHz signal. The simulations show that the heating area can be effectively controlled by using the cylindrical shield with adjustable aperture size. The heating efficiency is reduced as the aperture size decreases. If the small heating area is needed, it may require longer treatment time. Nevertheless, the efficiency of heat can be increased by varying the radius size of shielding plate. Moreover, we investigate the position of heating region by varying the orientation of the ferrite core in x direction. The effect of horizontal position of the ferrite core to the heating location is also studied. Simulations show that the heating position can be relocated by changing the orientation of the ferrite core with cylindrical shield. The advantage of the magnetic shielding system is that it can be used to applied for prevent the effects of hyperthermia cancer treatment by induction heating.

In this paper, the researches propose to study the effect of position of the pole coils to inductive regional heating. The focused is to determine the wide area which the heat is uniformly distributed. The result from this research was believed to be effectively applied to the cancer treatment. The design was pole coils which wear set of two pole coils, four pole coils, six pole coils and eight pole coils respectively. It was source operating at frequency of 2.45 GHz. The distance between lossy medium to pole coils was 3 mm., 5 mm. and 10 mm. respectively. The distributed of lossy medium was analyzing using finite difference time domain (FDTD). As the results of heating area simulation, many pole coils generated low heat, wide heating area and uniform distribution. However, less pole coil generated high heat and not uniform distribution. The pole coils was near lossy medium generated maximum heading, nevertheless it was not uniformly. Moreover, the pole coils was far lossy medium generate minimums heating, it was uniformly. The results from investigation can be applied and another advantage is its costs effectiveness.

This research focused on the adjustment of the heating distribution by controlling the energy supplied to the induction coil at the frequency of 2.45 GHz. The objective is to determine the area which the heat is uniformly distributed. The result from this research was believed to be effectively applied to the cancer treatment. The main equipment in the experiment was the induction coils which were sets of two coils and four coils, and each coil has its own power-supply unit. The result showed that the activation of supply units one at a time generated more heating area than the one when all units were activated at the same time. Moreover, the heating area depended on the number of coils and the temperature, so the understanding of these factors on the heat generation would significantly benefit the cancer treatment in the future.

A novel single element and array prototype antennas are presented for ultra wideband applications. The regular dipole and bow-tie shape are modified to a quasi rhomboid shape. The proposed antenna is designed on FR4 substrate, since it is small size, easily fabricated and low manufacturing cost. In antenna design, we analyze and simulate this antenna structure by using IE3D program. In order to verify the simulation results, the proposed antenna is realized and experimentally examined. In measurement, it is found that both antennas have impedance bandwidth of 120.55 % and 117.58 % (2:1 VSWR) which covered ultra wideband spectrum range with average gain of 4 and 6 dB at center frequency for a single element and an array structure, respectively. This antenna has a return loss lower than -10 dB all over the operating frequency and omni-directional patterns in azimuth plane. The advantage of the proposed antenna is that it can be used to design impulse receive-transmit system of ultra wideband applications.