A downconverting second harmonic self-oscillating mixer (SOM) is developed for low-cost wireless communications applications. Incorporating resonant cell in the SOM, we can provide suitable oscillation for generating LO and terminations to all major unwanted mixing products, leading to high conversion gain design. The proposed SOM was measured with 8.5 dB downconversion gain at the RF frequency of 8.2 GHz RF, LO frequency of 4.0 GHz, and IF frequency of 0.2 GHz. The proposed design achieves higher conversion gain than that of the SOM without resonant cell.
{"title":"A Second Harmonic Self-Oscillating Mixer Incorporating Resonant Cell Structure","authors":"L. Chiu, Q. Xue","doi":"10.1155/2012/565906","DOIUrl":"https://doi.org/10.1155/2012/565906","url":null,"abstract":"A downconverting second harmonic self-oscillating mixer (SOM) is developed for low-cost wireless communications applications. Incorporating resonant cell in the SOM, we can provide suitable oscillation for generating LO and terminations to all major unwanted mixing products, leading to high conversion gain design. The proposed SOM was measured with 8.5 dB downconversion gain at the RF frequency of 8.2 GHz RF, LO frequency of 4.0 GHz, and IF frequency of 0.2 GHz. The proposed design achieves higher conversion gain than that of the SOM without resonant cell.","PeriodicalId":232251,"journal":{"name":"International Journal of Microwave Science and Technology","volume":"25 4","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-09-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"120890060","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}
Raghida Hajj, M. Chatras, P. Blondy, O. Vendier, W. Tschanum, F. Courtade
A highly selective planar band pass filter is proposed for satellite receivers to suppress intermodulation components. The 4-pole filter has a center frequency of 19.825 GHz with a bandwidth of 240 MHz. The measured quality factor is over 600 and the insertion losses are 4.1 dB. The micromachining technological process is used to fabricate this filter. A BCB (benzocyclobutene) thin layer is used as an electrical and mechanical support for the filter. The compatibility of the BCB with the spatial constraints was tested. Various tests were accomplished for this purpose and the results of all these tests are presented in the paper. The tests showed a very small influence of the temperature variation and high temperature storage test and practically no influence of the radiation test on the circuit.
{"title":"Spatial Qualification Tests for Highly Selective Compact Micromachined Band Pass Planar Filters","authors":"Raghida Hajj, M. Chatras, P. Blondy, O. Vendier, W. Tschanum, F. Courtade","doi":"10.1155/2012/650754","DOIUrl":"https://doi.org/10.1155/2012/650754","url":null,"abstract":"A highly selective planar band pass filter is proposed for satellite receivers to suppress intermodulation components. The 4-pole filter has a center frequency of 19.825 GHz with a bandwidth of 240 MHz. The measured quality factor is over 600 and the insertion losses are 4.1 dB. The micromachining technological process is used to fabricate this filter. A BCB (benzocyclobutene) thin layer is used as an electrical and mechanical support for the filter. The compatibility of the BCB with the spatial constraints was tested. Various tests were accomplished for this purpose and the results of all these tests are presented in the paper. The tests showed a very small influence of the temperature variation and high temperature storage test and practically no influence of the radiation test on the circuit.","PeriodicalId":232251,"journal":{"name":"International Journal of Microwave Science and Technology","volume":"26 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-09-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129158815","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}
A novel internal antenna has been developed for indoor reception of UHF terrestrial digital TV broadcasting. The overall size of some configurations of the new antenna is less than 2 cm3, and its weight is less than 1 gm. It is made of a flexible material that can be bent or folded and shaped in any form. It is an unbalanced resonant antenna that does not need a matching circuit. The new antenna can be fully embedded inside TV sets or portable computers. It has a bandwidth of about 68%. Thus, it can also cover the bands of GSM and CDMA, which is advantageous in case of portable computers. The new antenna is linearly polarized. It can be easily modified to be dual polarized by combining two orthogonal antennas with one or two feed points. The overall efficiency of some configurations of the new indoor digital TV receiving antenna is more than 80%, and its peak gain is about 2 dBi over the whole UHF band. The peak gain can be increased to more than 5 dBi by adding EBG (electromagnetic bandgap) structures. The EBG structure also increases the efficiency to around 90%.
{"title":"A Novel Internal Dual-Polarized EBG Antenna for Indoor Reception of UHF Terrestrial Digital TV Broadcasting","authors":"M. Sanad, N. Hassan","doi":"10.1155/2012/873126","DOIUrl":"https://doi.org/10.1155/2012/873126","url":null,"abstract":"A novel internal antenna has been developed for indoor reception of UHF terrestrial digital TV broadcasting. The overall size of some configurations of the new antenna is less than 2 cm3, and its weight is less than 1 gm. It is made of a flexible material that can be bent or folded and shaped in any form. It is an unbalanced resonant antenna that does not need a matching circuit. The new antenna can be fully embedded inside TV sets or portable computers. It has a bandwidth of about 68%. Thus, it can also cover the bands of GSM and CDMA, which is advantageous in case of portable computers. The new antenna is linearly polarized. It can be easily modified to be dual polarized by combining two orthogonal antennas with one or two feed points. The overall efficiency of some configurations of the new indoor digital TV receiving antenna is more than 80%, and its peak gain is about 2 dBi over the whole UHF band. The peak gain can be increased to more than 5 dBi by adding EBG (electromagnetic bandgap) structures. The EBG structure also increases the efficiency to around 90%.","PeriodicalId":232251,"journal":{"name":"International Journal of Microwave Science and Technology","volume":"193 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-08-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125192714","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}
Arun Kumar, Vipin Kumar, B. Suthar, A. Bhargava, Kh. S. Singh, S. Ojha
Transmission characteristics of one-dimensional photonic crystal structure with a defect have been studied. Transfer matrix method has been employed to find the transmission spectra of the proposed structure. We consider a Si/air multilayer system and refractive index of Si layer has been taken as temperature dependent. As the refractive index of Si layer is a function of temperature of medium, so the central wavelength of the defect mode is a function of temperature. Variation in temperature causes the shifting of defect modes. It is found that the average change or shift in central wavelength of defect modes is 0.064 nm/K. This property can be exploited in the design of a temperature sensor.
{"title":"Wide Range Temperature Sensors Based on One-Dimensional Photonic Crystal with a Single Defect","authors":"Arun Kumar, Vipin Kumar, B. Suthar, A. Bhargava, Kh. S. Singh, S. Ojha","doi":"10.1155/2012/182793","DOIUrl":"https://doi.org/10.1155/2012/182793","url":null,"abstract":"Transmission characteristics of one-dimensional photonic crystal structure with a defect have been studied. Transfer matrix method has been employed to find the transmission spectra of the proposed structure. We consider a Si/air multilayer system and refractive index of Si layer has been taken as temperature dependent. As the refractive index of Si layer is a function of temperature of medium, so the central wavelength of the defect mode is a function of temperature. Variation in temperature causes the shifting of defect modes. It is found that the average change or shift in central wavelength of defect modes is 0.064 nm/K. This property can be exploited in the design of a temperature sensor.","PeriodicalId":232251,"journal":{"name":"International Journal of Microwave Science and Technology","volume":"332 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-08-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124683196","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}
This paper presents an alterative implementation of a shunt open-circuited stub for multilayer microwave circuit. With making use of the proposed implementation, a simple and compact bandstop filter with a district bandstop characteristics and a first spurious at the third harmonic is proposed. The proposed filter exhibits about 12.5% fractional bandwidth of −10 dB signal rejection at the center frequency of 2.04 GHz and flat group delay at the pass bands. Besides, by cascading a number of the proposed bandstop filters designed at the different frequencies, multiband bandstop filters can be easily realized. A dual- (tri-) band design at the center frequencies of 2 GHz and 3 GHz (and 4 GHz) is designed, realized, and measured. The proposed bandstop filter well suits the nowadays multilayer and compact radio frequency integrated circuit design.
{"title":"A Simple Microstrip Bandstop Filter Using Cross-Coupling Stubs","authors":"L. Chiu, Q. Xue","doi":"10.1155/2012/473030","DOIUrl":"https://doi.org/10.1155/2012/473030","url":null,"abstract":"This paper presents an alterative implementation of a shunt open-circuited stub for multilayer microwave circuit. With making use of the proposed implementation, a simple and compact bandstop filter with a district bandstop characteristics and a first spurious at the third harmonic is proposed. The proposed filter exhibits about 12.5% fractional bandwidth of −10 dB signal rejection at the center frequency of 2.04 GHz and flat group delay at the pass bands. Besides, by cascading a number of the proposed bandstop filters designed at the different frequencies, multiband bandstop filters can be easily realized. A dual- (tri-) band design at the center frequencies of 2 GHz and 3 GHz (and 4 GHz) is designed, realized, and measured. The proposed bandstop filter well suits the nowadays multilayer and compact radio frequency integrated circuit design.","PeriodicalId":232251,"journal":{"name":"International Journal of Microwave Science and Technology","volume":"23 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-08-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115422536","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}
B. Kapilevich, B. Litvak, M. Anisimov, D. Hardon, Y. Pinhasi
The paper describes the complex permittivity measurements of textiles and leathers in a free space at 330 GHz. The destructive role of the Rayleigh scattering effect is considered and the angular-invariant limit for an incidence angle has been found out experimentally within 25–30 degrees. If incidence angle exceeds this critical parameter, the uncertainty caused by the Rayleigh scattering is drastically increased preventing accurate measurements of the real and imaginary parts of a bulky material. The phenomenon must be taken into consideration in predicting shielding effectiveness of materials covering hidden object in concealed threat detection with millimeter-wave radar systems.
{"title":"Complex Permittivity Measurements of Textiles and Leather in a Free Space: An Angular-Invariant Approach","authors":"B. Kapilevich, B. Litvak, M. Anisimov, D. Hardon, Y. Pinhasi","doi":"10.1155/2012/375601","DOIUrl":"https://doi.org/10.1155/2012/375601","url":null,"abstract":"The paper describes the complex permittivity measurements of textiles and leathers in a free space at 330 GHz. The destructive role of the Rayleigh scattering effect is considered and the angular-invariant limit for an incidence angle has been found out experimentally within 25–30 degrees. If incidence angle exceeds this critical parameter, the uncertainty caused by the Rayleigh scattering is drastically increased preventing accurate measurements of the real and imaginary parts of a bulky material. The phenomenon must be taken into consideration in predicting shielding effectiveness of materials covering hidden object in concealed threat detection with millimeter-wave radar systems.","PeriodicalId":232251,"journal":{"name":"International Journal of Microwave Science and Technology","volume":"54 6 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-08-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116214588","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}
We present a low-cost millimeter-wave frequency synthesizer with ultralow phase noise, implemented using system-on-package (SoP) techniques for high-data-rate wireless personal area network (WPAN) systems operating in the unlicensed 60 GHz ISM band (57–64 GHz). The phase noise specification of the proposed frequency synthesizer is derived for a worst case scenario of an 802.11.3c system, which uses a 64-QAM 512-carrier-OFDM modulation, and a data rate of 5.775 Gbps. Our design approach adopts commercial-of-the-shelf (COTS) components integrated in a low-cost alumina-based miniature hybrid microwave integrated circuit (MHMIC) package. The proposed design approach reduces not only the system cost and time-to-market, but also enhances the system performance in comparison with system-on-chip (SoC) designs. The synthesizer has measured phase noise of −111.5 dBc/Hz at 1 MHz offset and integrated phase noise of 2.8° (simulated: 2.5°) measured at 57.6 GHz with output power of
{"title":"System-on-Package MHMIC Milimeter-Wave Frequency Synthesizer for 60 GHz WPANs","authors":"B. Spokoinyi, R. Amaya, I. Haroun, J. Wight","doi":"10.1155/2012/906516","DOIUrl":"https://doi.org/10.1155/2012/906516","url":null,"abstract":"We present a low-cost millimeter-wave frequency synthesizer with ultralow phase noise, implemented using system-on-package (SoP) techniques for high-data-rate wireless personal area network (WPAN) systems operating in the unlicensed 60 GHz ISM band (57–64 GHz). The phase noise specification of the proposed frequency synthesizer is derived for a worst case scenario of an 802.11.3c system, which uses a 64-QAM 512-carrier-OFDM modulation, and a data rate of 5.775 Gbps. Our design approach adopts commercial-of-the-shelf (COTS) components integrated in a low-cost alumina-based miniature hybrid microwave integrated circuit (MHMIC) package. The proposed design approach reduces not only the system cost and time-to-market, but also enhances the system performance in comparison with system-on-chip (SoC) designs. The synthesizer has measured phase noise of −111.5 dBc/Hz at 1 MHz offset and integrated phase noise of 2.8° (simulated: 2.5°) measured at 57.6 GHz with output power of","PeriodicalId":232251,"journal":{"name":"International Journal of Microwave Science and Technology","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-07-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116062991","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}
A commercial vinyl ester resin supplied by Hetron Chemical Pty. was reinforced with varying percentages by weight of sawdust. The sawdust particles were sieved into 3 different sizes, which were <300 μm, 300–425 μm, and 425–1180 μm, respectively, with a view to increase its fracture toughness for civil and structural applications. The sawdust used varied from 0% w/t to 15% w/t in step of 5% w/t. For higher w/t% of sawdust, the mixture would be too sticky to be mixed and cast. The cast composites were cured in ambient conditions and then postcured in microwave irradiation. They were then tested for fracture toughness using short bar tests. The values of fracture toughness of the composites increased with increasing particulate size, and this is due to the size distribution of the filler. It was found that the optimum amount of sawdust (425–1180 μm) was 15% w/t, with which the increase in fracture toughness was 126% as compared to neat resin and the reduction in cost was 15%. Furthermore, the optimum amount of sawdust (300–425 μm) was also 15% w/t, with which the increase in fracture toughness was 28.3% as compared to neat resin and the reduction in cost was again 15%.
{"title":"Fracture Toughness of Vinyl Ester Composites Reinforced with Sawdust and Postcured in Microwaves","authors":"H. Ku, M. Prajapati, M. Trada","doi":"10.1155/2012/152726","DOIUrl":"https://doi.org/10.1155/2012/152726","url":null,"abstract":"A commercial vinyl ester resin supplied by Hetron Chemical Pty. was reinforced with varying percentages by weight of sawdust. The sawdust particles were sieved into 3 different sizes, which were <300 μm, 300–425 μm, and 425–1180 μm, respectively, with a view to increase its fracture toughness for civil and structural applications. The sawdust used varied from 0% w/t to 15% w/t in step of 5% w/t. For higher w/t% of sawdust, the mixture would be too sticky to be mixed and cast. The cast composites were cured in ambient conditions and then postcured in microwave irradiation. They were then tested for fracture toughness using short bar tests. The values of fracture toughness of the composites increased with increasing particulate size, and this is due to the size distribution of the filler. It was found that the optimum amount of sawdust (425–1180 μm) was 15% w/t, with which the increase in fracture toughness was 126% as compared to neat resin and the reduction in cost was 15%. Furthermore, the optimum amount of sawdust (300–425 μm) was also 15% w/t, with which the increase in fracture toughness was 28.3% as compared to neat resin and the reduction in cost was again 15%.","PeriodicalId":232251,"journal":{"name":"International Journal of Microwave Science and Technology","volume":"64 15 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-07-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116537513","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}
An approach to reconstruct buried objects is proposed. It is based on the integral equations of the electromagnetic inverse scattering problem, written in terms of the Green’s function for half-space geometries. The full nonlinearity of the problem is exploited in order to inspect strong scatterers. After discretization of the continuous model, the resulting equations are solved in a regularization sense by means of a two-step inexact Newton algorithm. The capabilities and limitations of the method are evaluated by means of some numerical simulations.
{"title":"Buried Object Detection by an Inexact Newton Method Applied to Nonlinear Inverse Scattering","authors":"M. Pastorino, A. Randazzo","doi":"10.1155/2012/637301","DOIUrl":"https://doi.org/10.1155/2012/637301","url":null,"abstract":"An approach to reconstruct buried objects is proposed. It is based on the integral equations of the electromagnetic inverse scattering problem, written in terms of the Green’s function for half-space geometries. The full nonlinearity of the problem is exploited in order to inspect strong scatterers. After discretization of the continuous model, the resulting equations are solved in a regularization sense by means of a two-step inexact Newton algorithm. The capabilities and limitations of the method are evaluated by means of some numerical simulations.","PeriodicalId":232251,"journal":{"name":"International Journal of Microwave Science and Technology","volume":"19 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-07-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122916685","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}
Transformer-based shunt single pole, double-throw (SPDT) switches are analyzed, and design equations are provided. A mm-wave transformer-based SPDT shunt switch prototype was designed and fabricated in 90 nm digital CMOS process. It has a minimum insertion loss of 3.4 dB at 50 GHz from the single pole to the ON-thru port and a leakage of 19 dB from the single pole to the OFF-thru port. The isolation is 13.7 dB between the two thru ports. Large signal measurements verify that the switch is capable of handling
{"title":"Analysis and Design of Transformer-Based mm-Wave Transmit/Receive Switches","authors":"E. Adabi, A. Niknejad","doi":"10.1155/2012/302302","DOIUrl":"https://doi.org/10.1155/2012/302302","url":null,"abstract":"Transformer-based shunt single pole, double-throw (SPDT) switches are analyzed, and design equations are provided. A mm-wave transformer-based SPDT shunt switch prototype was designed and fabricated in 90 nm digital CMOS process. It has a minimum insertion loss of 3.4 dB at 50 GHz from the single pole to the ON-thru port and a leakage of 19 dB from the single pole to the OFF-thru port. The isolation is 13.7 dB between the two thru ports. Large signal measurements verify that the switch is capable of handling","PeriodicalId":232251,"journal":{"name":"International Journal of Microwave Science and Technology","volume":"19 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-07-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125126555","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}
京公网安备 11010802042870号
京ICP备2023020795号-1
扫码关注我们
求助内容：
应助结果提醒方式：