{"title":"Phase based sector resolution in angle of arrival (AoA) computation using a five element circular array","authors":"C. Viswanadham, A. Singh","doi":"10.1109/IMARC.2015.7411368","DOIUrl":"https://doi.org/10.1109/IMARC.2015.7411368","url":null,"abstract":"Many techniques are employed to passively measure Angle of Arrival (AOA) in different EW systems viz. Amplitude Comparison, Phase Comparison, Time Difference of arrival (TDOA) and Rotary Direction Finding (RDF). `Base Line Interferometry (BLI)' is a phase comparison technique. It is used in EW systems where high accuracy and high sensitivity are required. In this paper, a five element circular array of twisted dipoles is taken for realization of BLI based DF system. An algorithm, which uses only phase data to compute Angle of Arrival (AOA) is developed. The most critical part of this algorithm is to select the appropriate base line (sector selection) for applying the standard BLI formula. This approach offers the benefit of simpler and substantially less time-taking calibration process, when compared with correlative interferometry based systems using similar antenna system. This also offers the benefit of low form factor and less hardware (as no ADF is required) when compared with linear BLI systems.","PeriodicalId":307742,"journal":{"name":"2015 IEEE MTT-S International Microwave and RF Conference (IMaRC)","volume":"28 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114375288","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}
{"title":"A flexible, ultra thin, frequency-selective-surface based absorber film for the radar cross section reduction of a cubical object","authors":"H. Baskey, B. Ghai, M. J. Akhtar","doi":"10.1109/IMARC.2015.7411384","DOIUrl":"https://doi.org/10.1109/IMARC.2015.7411384","url":null,"abstract":"This paper presents the design, simulation and fabrication of a frequency selective surface (FSS) based unit cell structure over a flexible polyimide film for the effective electromagnetic absorption. The proposed FSS structure is designed using the splitted rings, where the unit cell dimensions are selected for effective EM absorption in the X band. The simulated results show absorption of 99.25% at 11.20 GHz having film thickness of 135μm. The proposed absorber film is effectively being used for the radar cross section (RCS) reduction of a cubical object. The proposed structure is fabricated and tested for the electromagnetic absorption as well as for the RCS reduction. A close match between the simulated and the experimental results is observed. The proposed FSS structure is ultrathin, flexible and flame retardant, which makes it a good potential candidate for the RF stealth technology.","PeriodicalId":307742,"journal":{"name":"2015 IEEE MTT-S International Microwave and RF Conference (IMaRC)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129519413","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}
{"title":"Compact two-element UWB fractal monopole MIMO antenna using T-shaped reflecting stub for high isolation","authors":"S. Rajkumar, K. Selvan, P. H. Rao","doi":"10.1109/IMARC.2015.7411437","DOIUrl":"https://doi.org/10.1109/IMARC.2015.7411437","url":null,"abstract":"In this paper, a compact 2-element ultra wideband MIMO antenna system measuring 20×32 mm2 is proposed. The radiating element of the monopole antenna configuration is fractal shaped, and is fed by a coplanar waveguide independently. A T-shaped reflecting stub is placed between the two antennas to reduce mutual coupling and hence to improve isolation. The antenna performance is studied in terms of impedance matching, isolation, radiation pattern, and Envelope Correlation Coefficient (ECC). The measured result shows that the proposed antenna operates in the UWB frequency range of 3.1-7.5 GHz with S11 ≤ -10dB (S11 ≤ -8dB for 7.5-10.6 GHz) and S21 ≤ -15dB. The antenna exhibits an ECC of less than 0.06. The proposed antenna configuration provides beam tilting over the operating frequency due to the presence of the T-shaped stub, thus creating pattern diversity.","PeriodicalId":307742,"journal":{"name":"2015 IEEE MTT-S International Microwave and RF Conference (IMaRC)","volume":"18 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133427795","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}
{"title":"Computer-aided-design of an 18–40 GHz MMIC low noise amplifier using RLC and series inductive feedback","authors":"Paramita Banerjee, Arijit Majumder","doi":"10.1109/IMARC.2015.7411398","DOIUrl":"https://doi.org/10.1109/IMARC.2015.7411398","url":null,"abstract":"This paper presents the design and development of a MMIC based broadband low noise amplifier using a GaAs based pHEMT of 0.15 pm gate length. A 3 stage cascaded amplifier configuration has been chosen for the design. Series inductive feedback and RLC feedback have been used simultaneously in order to achieve improved stability and gain flatness over the required bandwidth. The design, simulation and optimization are carried out using Agilent's Advanced Design System (ADS). A gain of 15.8±2dB and a maximum noise figure of 3.9 dB over a frequency band of 18-40 GHz have been achieved. The amplifier finds its application in Millimeter wave Imaging, Surveillance System, Wide-Band and UWB Radar, Space and Test Instrumentation.","PeriodicalId":307742,"journal":{"name":"2015 IEEE MTT-S International Microwave and RF Conference (IMaRC)","volume":"134 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133103522","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}
V. Rao, Vipin W. Paradkar, D. Jahagirdar, G. Kumar
{"title":"Wideband broad beamwidth circularly polarized stacked microstrip patch antenna with RF switch for data link application","authors":"V. Rao, Vipin W. Paradkar, D. Jahagirdar, G. Kumar","doi":"10.1109/IMARC.2015.7411433","DOIUrl":"https://doi.org/10.1109/IMARC.2015.7411433","url":null,"abstract":"In this paper, wideband circularly polarized stacked microstrip antenna in C-band with broad beam width for ground system of two way data link application has been proposed. This antenna is useful for surface to air communication like aircraft and missile applications. The proposed antenna has been analyzed using the FEM-based HFSS software. It is designed with different layers of dielectric substrates having different heights. The single diagonal feed technique is used to achieve circular polarization. Broad bandwidth is obtained by stacking two rectangular patches, which are electromagnetically coupled. The prototype is fabricated and the measured results are in good agreement with simulated results. The antenna has directive gain of more than 7dBic over the bandwidth. The -10dB return loss bandwidth is around 1200MHz (22%) and 3dB axial ratio bandwidth is around 700 MHz (14%).","PeriodicalId":307742,"journal":{"name":"2015 IEEE MTT-S International Microwave and RF Conference (IMaRC)","volume":"181 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132136134","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}
{"title":"CPW fed triple band antenna for sensor application","authors":"Harishankar Prasad, M. J. Akhtar","doi":"10.1109/IMARC.2015.7411394","DOIUrl":"https://doi.org/10.1109/IMARC.2015.7411394","url":null,"abstract":"In recent year, the demand for multiple frequency band antennas has increased tremendously for a number of RF and microwave applications. The advantage of multi band antenna is that the same device can be used for different frequency bands in order to cater to multiple services. In this paper, a triple band antenna on a very thin substrate with single side cladding is designed and developed, which can also be reshaped in order to fit to any test object. The proposed antenna is specifically designed for the microwave imaging and non-destructive testing (NDT) of various structures and media, where it has to be closely fitted around the test object. It is low cost, light weight and easy to integrate with microwave monolithic integrated circuits and other electronic devices. The proposed antenna is having gain of 5.22 dBi, and bandwidth of 720, 1300 and 1170 MHz is observed at three designated bands. The simulated and measured scattering parameters are having good agreement with the typical variation of less than 3 percent.","PeriodicalId":307742,"journal":{"name":"2015 IEEE MTT-S International Microwave and RF Conference (IMaRC)","volume":"48 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122354723","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}
{"title":"GaN based L-band high power and high efficiency pulsed transmitter","authors":"S. K. Garg, S. Aich, J. Dhar","doi":"10.1109/IMARC.2015.7411438","DOIUrl":"https://doi.org/10.1109/IMARC.2015.7411438","url":null,"abstract":"This paper illustrates the design and development of L-Band GaN based high power, high efficiency pulsed transmitter to deliver peak output power of 50W at centre frequency of 1.25 GHz with 75 MHz bandwidth. This L-Band transmitter has been designed and developed for dual frequency (L&S-Band) airborne SAR mission. Size, weight and power constraints led to the selection of GaN HEMT devices which offer inherently higher efficiency compared to GaAsFET devices. Class-F approach has been used for the design of power amplifier stages to enhance the efficiency of transmitter. Power Added Efficiency (PAE) of more than 50% is achieved from the integrated transmitter. Transmitter was characterized for all 64 phase states using a 6-bit digital phase shifter. Comparison of simulated and test results of various amplifier stages along with summary of specifications and test results of pulsed transmitter is given to validate the design.","PeriodicalId":307742,"journal":{"name":"2015 IEEE MTT-S International Microwave and RF Conference (IMaRC)","volume":"14 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114967425","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}
{"title":"MIMO antenna using castor leaf-shaped quasi-self-complemetary elements for broadband applications","authors":"S. R. Patre, S. Singh","doi":"10.1109/IMARC.2015.7411400","DOIUrl":"https://doi.org/10.1109/IMARC.2015.7411400","url":null,"abstract":"This paper presents the simulation study of multiple-input-multiple-output (MIMO) antenna using two castor leaf-shaped quasi-self-complementary elements for broadband applications. Each antenna element having conducting patch and complementary slot along with in-built matching circuit is fed using coplanar waveguide (CPW) which makes the antenna single-sided. The optimal design of the proposed MIMO antenna provides -10 dB reflection coefficient bandwidth of 2.2-13.1 GHz. The mutual coupling between the two elements of the antenna is less than -15 dB without using any isolation technique and the envelop correlation coefficient is less than 0.02 over its operating frequency band. Because of the mirror-image arrangement of antenna elements, the direction of maximum radiation is opposite to each other when the excitation is changed from one port to another. The proposed MIMO antenna can be a good candidate for devices that utilize broad bandwidth (3.1-10.6 GHz) along with Bluetooth spectrum.","PeriodicalId":307742,"journal":{"name":"2015 IEEE MTT-S International Microwave and RF Conference (IMaRC)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130193731","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}
{"title":"Dual mode bandpass filter using trefoil torus knot resonator","authors":"S. V. Kumar, A. Harish","doi":"10.1109/IMARC.2015.7411408","DOIUrl":"https://doi.org/10.1109/IMARC.2015.7411408","url":null,"abstract":"In this paper we present compact dual mode band pass filter based on trefoil torus knot resonator. The resonator is realized using additive manufacturing technology. Size of the resonator is 0.16 λ at the center frequency of operation. Fabricated resonator prototype is about half the size of ring resonator. Simulated and measured results are presented which are in good agreement.","PeriodicalId":307742,"journal":{"name":"2015 IEEE MTT-S International Microwave and RF Conference (IMaRC)","volume":"62 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124424863","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}
{"title":"A novel approach to design of a squared cosine (Cos2) pulse modulated power amplifier used for airborne navigational applications","authors":"P. Venkaiah, Ramesh Avala","doi":"10.1109/IMARC.2015.7411393","DOIUrl":"https://doi.org/10.1109/IMARC.2015.7411393","url":null,"abstract":"A pulsed power amplifier that achieves stringent spectral requirements at RF frequencies by significantly reducing the side band radiations using a squared cosine pulse modulation scheme is proposed. The scheme compliance the requirements of MIL STD 291C, an interface standard for Tactical Air Navigation, TACAN signal. The Squared Cosine baseband is generated using an FPGA by employing a Look-Up table based method. The digitally generated samples from FPGA are passed through a DAC followed by a reconstruction filter for its smoothening. High slew rate Opamp followed by a power MOSFET further amplifies the pulse level and current drive requirements, to implement drain modulation of GaN based RF power amplifier. The designs are tested on a developed board with integrated power amplifier in the frequency band of 1025MHz to 1150MHz in step of 1MHz. The test results are matching with theoretical and simulated results.","PeriodicalId":307742,"journal":{"name":"2015 IEEE MTT-S International Microwave and RF Conference (IMaRC)","volume":"69 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115874691","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}