Pub Date : 2008-12-01DOI: 10.1109/RFM.2008.4897454
A.K.H. Obsiye, H. E. Abdel-Raouf, R. El-Islam
In this paper we present the design of a modified crescent antenna for Ultrawideband (UWB) Radio Frequency identification (RFID) tag. Different studies to optimize the design of this antenna for the UWB-RFID system have been performed, particularly to overcome the main challenges such as minimizing the size of the antenna, improving its read range, and the effects of the metallic objects on the antenna performance. As a result of this study, the proposed antenna has a maximum read range between 5.4 m and 7.5 m with the ability to work in the UWB when the antenna is close to metallic objects.
{"title":"Modified printed crescent patch antenna for Ultrawideband RFID (UWB-RFID) tag","authors":"A.K.H. Obsiye, H. E. Abdel-Raouf, R. El-Islam","doi":"10.1109/RFM.2008.4897454","DOIUrl":"https://doi.org/10.1109/RFM.2008.4897454","url":null,"abstract":"In this paper we present the design of a modified crescent antenna for Ultrawideband (UWB) Radio Frequency identification (RFID) tag. Different studies to optimize the design of this antenna for the UWB-RFID system have been performed, particularly to overcome the main challenges such as minimizing the size of the antenna, improving its read range, and the effects of the metallic objects on the antenna performance. As a result of this study, the proposed antenna has a maximum read range between 5.4 m and 7.5 m with the ability to work in the UWB when the antenna is close to metallic objects.","PeriodicalId":329128,"journal":{"name":"2008 IEEE International RF and Microwave Conference","volume":"2 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130990166","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2008-12-01DOI: 10.1109/RFM.2008.4897420
F. N. Khan, F. Mohammadi, M. Yagoub
In this work, the authors present a highly efficient GaN HEMT Class-F amplifier designed for Universal Mobile Telecommunications Systems using Wideband Code Division Multiple Access (UMTS/WCDMA). The amplifier has a peak PAE of 76% with an output power of 10.5 W. A comparison between class-F and inverse Class-F was also made.
{"title":"A GaN HEMT Class-F amplifier for UMTS/WCDMA applications","authors":"F. N. Khan, F. Mohammadi, M. Yagoub","doi":"10.1109/RFM.2008.4897420","DOIUrl":"https://doi.org/10.1109/RFM.2008.4897420","url":null,"abstract":"In this work, the authors present a highly efficient GaN HEMT Class-F amplifier designed for Universal Mobile Telecommunications Systems using Wideband Code Division Multiple Access (UMTS/WCDMA). The amplifier has a peak PAE of 76% with an output power of 10.5 W. A comparison between class-F and inverse Class-F was also made.","PeriodicalId":329128,"journal":{"name":"2008 IEEE International RF and Microwave Conference","volume":"3 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125444495","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2008-12-01DOI: 10.1109/RFM.2008.4897405
T. Masri, M. Rahim, F. Zubir, O. Ayop, M. Karim, H. Majid
For a point-to-point communication system, an antenna array with high gain is essential and in this work, by incorporating electromagnetic band gap (EBG) structures at a specific location within the antenna's peripherals, the gain of the antenna could be enhanced further. The EBG structures reduced mutual couplings between the adjacent patches thus make them radiates effectively. On the other hand, the EBG structures located at the edge of the antenna suppressed surface waves and prevent it from propagating to the edges, thus reduced the side and back lobes. This further enhances the front radiation characteristics of the antenna and also increased the gain. The techniques and guidelines on how to achieve the objectives is presented and the simulated and measured results complement each other.
{"title":"Microstrip antenna array's gain enhancement via Electromagnetic Band Gap structures","authors":"T. Masri, M. Rahim, F. Zubir, O. Ayop, M. Karim, H. Majid","doi":"10.1109/RFM.2008.4897405","DOIUrl":"https://doi.org/10.1109/RFM.2008.4897405","url":null,"abstract":"For a point-to-point communication system, an antenna array with high gain is essential and in this work, by incorporating electromagnetic band gap (EBG) structures at a specific location within the antenna's peripherals, the gain of the antenna could be enhanced further. The EBG structures reduced mutual couplings between the adjacent patches thus make them radiates effectively. On the other hand, the EBG structures located at the edge of the antenna suppressed surface waves and prevent it from propagating to the edges, thus reduced the side and back lobes. This further enhances the front radiation characteristics of the antenna and also increased the gain. The techniques and guidelines on how to achieve the objectives is presented and the simulated and measured results complement each other.","PeriodicalId":329128,"journal":{"name":"2008 IEEE International RF and Microwave Conference","volume":"5 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126832132","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2008-12-01DOI: 10.1109/RFM.2008.4897393
A.S. Chahine, U. Okonkwo, R. Ngah
Radio-over-fiber (ROF) technology has several advantages such as providing huge bandwidth, inherent immunity to electromagnetic interference and reduced power consumption. This paper presents a simulation to investigate the performance of orthogonal frequency division multiplexing (OFDM) as a modulation technique to transmit the basebands signal over fiber. The model contains a laser diode used as optical modulator to convert the signal from baseband to optical frequency. The QPSK-OFDM transmitted signal and power spectrum are obtained for both of AWGN and optical fiber link channels. The study reveals that the OFDM performance on the optical fiber link in terms of spectrum containment is nearly similar to that on AWGN channel. The significance of this study comes from the promising future of using optical fibers to transmit radio signal. Consequently the model of this paper can be used with different wireless communication systems such as wireless LANs and digital video broadcasting (DVB) and it is supporting to the 4th generation cellular systems. The details of design and simulated results for the proposed model are presented and discussed.
{"title":"Study the performance of OFDM radio over fiber for wireless communication systems","authors":"A.S. Chahine, U. Okonkwo, R. Ngah","doi":"10.1109/RFM.2008.4897393","DOIUrl":"https://doi.org/10.1109/RFM.2008.4897393","url":null,"abstract":"Radio-over-fiber (ROF) technology has several advantages such as providing huge bandwidth, inherent immunity to electromagnetic interference and reduced power consumption. This paper presents a simulation to investigate the performance of orthogonal frequency division multiplexing (OFDM) as a modulation technique to transmit the basebands signal over fiber. The model contains a laser diode used as optical modulator to convert the signal from baseband to optical frequency. The QPSK-OFDM transmitted signal and power spectrum are obtained for both of AWGN and optical fiber link channels. The study reveals that the OFDM performance on the optical fiber link in terms of spectrum containment is nearly similar to that on AWGN channel. The significance of this study comes from the promising future of using optical fibers to transmit radio signal. Consequently the model of this paper can be used with different wireless communication systems such as wireless LANs and digital video broadcasting (DVB) and it is supporting to the 4th generation cellular systems. The details of design and simulated results for the proposed model are presented and discussed.","PeriodicalId":329128,"journal":{"name":"2008 IEEE International RF and Microwave Conference","volume":"36 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125202510","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2008-12-01DOI: 10.1109/RFM.2008.4897354
K. Ito
In recent years, various types of medical applications of antennas have widely been investigated and reported. Typical recent applications are in Information transmission such as RFID (radio frequency identification)/wearable or implantable monitor and wireless telemedicine/mobile health system and in diagnosis such as MRI (magnetic resonance imaging)/fMRI and microwave CT (computed tomography)/radiometry. Other application includes in treatment such as thermal therapy (Hyperthermia, Coagulation, etc) and microwave knife. In this presentation, three different types of antennas which have been studied in our laboratory are introduced. Firstly, a pretty small antenna for an implantable monitoring system is presented. An H-shaped cavity slot antenna is a candidate for such a system. Some numerical and experimental characteristics of the antenna are demonstrated. Secondly, some different antennas or ldquoRF coilsrdquo for MRI systems are introduced. In addition, SAR (specific absorption rate) distributions in the abdomen of a pregnant woman generated in a bird cage coil are illustrated. Finally, after a brief overview of thermal therapy and microwave heating, coaxial-slot antennas and array applicators composed of several coaxial-slot antennas for minimally invasive microwave thermal therapies are introduced. Then a few results of actual clinical trials by use of the coaxial-slot antennas are demonstrated from a technical point of view. Other therapeutic applications of the coaxial-slot antennas such as hyperthermic treatment for brain tumor and intracavitary hyperthermia for bile duct carcinoma are introduced.
{"title":"Keynote 2: Microwave antennas for medical applications","authors":"K. Ito","doi":"10.1109/RFM.2008.4897354","DOIUrl":"https://doi.org/10.1109/RFM.2008.4897354","url":null,"abstract":"In recent years, various types of medical applications of antennas have widely been investigated and reported. Typical recent applications are in Information transmission such as RFID (radio frequency identification)/wearable or implantable monitor and wireless telemedicine/mobile health system and in diagnosis such as MRI (magnetic resonance imaging)/fMRI and microwave CT (computed tomography)/radiometry. Other application includes in treatment such as thermal therapy (Hyperthermia, Coagulation, etc) and microwave knife. In this presentation, three different types of antennas which have been studied in our laboratory are introduced. Firstly, a pretty small antenna for an implantable monitoring system is presented. An H-shaped cavity slot antenna is a candidate for such a system. Some numerical and experimental characteristics of the antenna are demonstrated. Secondly, some different antennas or ldquoRF coilsrdquo for MRI systems are introduced. In addition, SAR (specific absorption rate) distributions in the abdomen of a pregnant woman generated in a bird cage coil are illustrated. Finally, after a brief overview of thermal therapy and microwave heating, coaxial-slot antennas and array applicators composed of several coaxial-slot antennas for minimally invasive microwave thermal therapies are introduced. Then a few results of actual clinical trials by use of the coaxial-slot antennas are demonstrated from a technical point of view. Other therapeutic applications of the coaxial-slot antennas such as hyperthermic treatment for brain tumor and intracavitary hyperthermia for bile duct carcinoma are introduced.","PeriodicalId":329128,"journal":{"name":"2008 IEEE International RF and Microwave Conference","volume":"31 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122641651","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2008-12-01DOI: 10.1109/RFM.2008.4897469
Wen-Lin Chen, Sheng-Fuh Chang, Kun-Ming Chen, K. Liao, G. Huang, J. Chang
A hybrid OPEN model, which consists of equivalent circuit model and behavior transmission line (TL) model, is proposed to accurately extract device characteristics. The proposed method requires only one OPEN dummy structure so the silicon occupation area is efficiently reduced. The other benefit is it avoids the errors, which is occurred while performing the classical de-embedding procedure. A Ka-band CPW filter is fabricated in 130 nm RF CMOS technique to prove this method is efficient up to 67 GHz.
{"title":"A hybrid OPEN model technique for accurate device characterization","authors":"Wen-Lin Chen, Sheng-Fuh Chang, Kun-Ming Chen, K. Liao, G. Huang, J. Chang","doi":"10.1109/RFM.2008.4897469","DOIUrl":"https://doi.org/10.1109/RFM.2008.4897469","url":null,"abstract":"A hybrid OPEN model, which consists of equivalent circuit model and behavior transmission line (TL) model, is proposed to accurately extract device characteristics. The proposed method requires only one OPEN dummy structure so the silicon occupation area is efficiently reduced. The other benefit is it avoids the errors, which is occurred while performing the classical de-embedding procedure. A Ka-band CPW filter is fabricated in 130 nm RF CMOS technique to prove this method is efficient up to 67 GHz.","PeriodicalId":329128,"journal":{"name":"2008 IEEE International RF and Microwave Conference","volume":"93 Pt A 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122656086","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2008-12-01DOI: 10.1109/RFM.2008.4897394
W. H. Choo, M. Kawasaki, F. Kung
The demand for industry-ready RF engineering graduates is increasing in tandem with the growth in wireless industries, and reduction in product time-to-market, creating an acute shortage of RF engineers world-wide. The complexities of RF theories, lack of exposure to relevant industry tools and missing domain knowledge in various functions within the industry further aggravates the situation. This paper outlines key aspects of developing a comprehensive teaching solution for RF engineers that closes this gap and benefits universities and industry. Critical job functions, skill sets, domain knowledge and engineering concepts are mapped systematically, resulting in a comprehensive solution encompassing teaching slide sets, a training kit, industry-standard measurement equipment, RF design software, test automation software, a course quality management template, problem-based assignments and train-the-trainer program.
{"title":"RF engineering education - the approach to bridging the industry gap","authors":"W. H. Choo, M. Kawasaki, F. Kung","doi":"10.1109/RFM.2008.4897394","DOIUrl":"https://doi.org/10.1109/RFM.2008.4897394","url":null,"abstract":"The demand for industry-ready RF engineering graduates is increasing in tandem with the growth in wireless industries, and reduction in product time-to-market, creating an acute shortage of RF engineers world-wide. The complexities of RF theories, lack of exposure to relevant industry tools and missing domain knowledge in various functions within the industry further aggravates the situation. This paper outlines key aspects of developing a comprehensive teaching solution for RF engineers that closes this gap and benefits universities and industry. Critical job functions, skill sets, domain knowledge and engineering concepts are mapped systematically, resulting in a comprehensive solution encompassing teaching slide sets, a training kit, industry-standard measurement equipment, RF design software, test automation software, a course quality management template, problem-based assignments and train-the-trainer program.","PeriodicalId":329128,"journal":{"name":"2008 IEEE International RF and Microwave Conference","volume":"21 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131756442","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2008-12-01DOI: 10.1109/RFM.2008.4897381
A. D. Usman, W. F. Wan Ahmad
Rapid development in the field of telecommunication industries and the lagging phase to which the exposure assessment results, calls for immediate intervention by scientist and engineers. In order to respond to public outcry, who are daily exposed to various sort of electromagnetic field radiations, a critical look on the electromagnetic field exposure guidelines and assessment of its effectiveness revealed that the guidelines are conservatives and are based only on short-term immediate health effects. In order to accommodate for the unforeseen, a lower limit of 1 w/kg instead of 4 w/kg of the SAR is recommended with a safety margin of 100 for occupational and 10 for the general public. Possible solutions to the gap identified were also provided.
{"title":"RF EM exposure: The issues, the debate and the realities","authors":"A. D. Usman, W. F. Wan Ahmad","doi":"10.1109/RFM.2008.4897381","DOIUrl":"https://doi.org/10.1109/RFM.2008.4897381","url":null,"abstract":"Rapid development in the field of telecommunication industries and the lagging phase to which the exposure assessment results, calls for immediate intervention by scientist and engineers. In order to respond to public outcry, who are daily exposed to various sort of electromagnetic field radiations, a critical look on the electromagnetic field exposure guidelines and assessment of its effectiveness revealed that the guidelines are conservatives and are based only on short-term immediate health effects. In order to accommodate for the unforeseen, a lower limit of 1 w/kg instead of 4 w/kg of the SAR is recommended with a safety margin of 100 for occupational and 10 for the general public. Possible solutions to the gap identified were also provided.","PeriodicalId":329128,"journal":{"name":"2008 IEEE International RF and Microwave Conference","volume":"136 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121252248","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2008-12-01DOI: 10.1109/RFM.2008.4897445
F. Zubir, M. Rahim, T. Masri, M. Karim
This paper described the design and analysis of linear and circular array microstrip antenna. A linear and circular array with eight elements have been fabricated and measured at operating frequency of 2.4 GHz. The performances between two antennas have been analyzed in terms of return loss, radiation pattern, half power beamwidth, polarization and gain. It shows that from the measured and simulated results, the circular array microstrip antenna has better gain and return loss with equal half-power beamwidth in E-plane and H-plane. The bandwidth percentage for eight elements circular array is wider. Both designs have linear type of polarization.
{"title":"Comparison between circular array and linear array microstrip antenna","authors":"F. Zubir, M. Rahim, T. Masri, M. Karim","doi":"10.1109/RFM.2008.4897445","DOIUrl":"https://doi.org/10.1109/RFM.2008.4897445","url":null,"abstract":"This paper described the design and analysis of linear and circular array microstrip antenna. A linear and circular array with eight elements have been fabricated and measured at operating frequency of 2.4 GHz. The performances between two antennas have been analyzed in terms of return loss, radiation pattern, half power beamwidth, polarization and gain. It shows that from the measured and simulated results, the circular array microstrip antenna has better gain and return loss with equal half-power beamwidth in E-plane and H-plane. The bandwidth percentage for eight elements circular array is wider. Both designs have linear type of polarization.","PeriodicalId":329128,"journal":{"name":"2008 IEEE International RF and Microwave Conference","volume":"119 2","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114114173","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2008-12-01DOI: 10.1109/RFM.2008.4897404
M. F. Ain, S. Hassan, M.N. Ismail, M. A. Othman, M.R. Jaffar, A. Othman, A. A. Sulaiman, M.A. Zakariyya, S. Sreekantan, S. D. Hutagalung, Z. Ahmad
In this paper, dielectric resonator antenna operated at 3.5 GHz was design and simulated using CST Microwave Studio and subsequently fabricated. Direct microstrip line of 50 Omega was used as the feeder. In this design, rectangular shape was used as the dielectric resonator as it offers more option to control the resonant frequency. The position of rectangular DR was varied to determine the best coupling and the distance was found to be 6 mm. The simulated results of the return loss, resonant frequency together with radiation pattern were compared with the measured results. It was found that rectangular DRA has potential to be used in wireless system.
{"title":"3.5 GHz rectangular dielectric resonator antenna","authors":"M. F. Ain, S. Hassan, M.N. Ismail, M. A. Othman, M.R. Jaffar, A. Othman, A. A. Sulaiman, M.A. Zakariyya, S. Sreekantan, S. D. Hutagalung, Z. Ahmad","doi":"10.1109/RFM.2008.4897404","DOIUrl":"https://doi.org/10.1109/RFM.2008.4897404","url":null,"abstract":"In this paper, dielectric resonator antenna operated at 3.5 GHz was design and simulated using CST Microwave Studio and subsequently fabricated. Direct microstrip line of 50 Omega was used as the feeder. In this design, rectangular shape was used as the dielectric resonator as it offers more option to control the resonant frequency. The position of rectangular DR was varied to determine the best coupling and the distance was found to be 6 mm. The simulated results of the return loss, resonant frequency together with radiation pattern were compared with the measured results. It was found that rectangular DRA has potential to be used in wireless system.","PeriodicalId":329128,"journal":{"name":"2008 IEEE International RF and Microwave Conference","volume":"4 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114219902","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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