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This publication is a work of the U.S. Government as defined in Title 17, United States Code, Section 101. As such, it is in the public domain, and under the provisions of Title 17, United States Code, Section 105, may not be copyrighted. ; The 18th Annual International IEEE Symposium on Field-Programmable Custom Computing Machines, Charlotte, NC, May 2-4, 2010, pp. 265-272 ; We show that there is a significant benefit to using a reconfigurable computer to enumerate bent Boolean functions for crypographic applications. Bent functions are rare, and the only known way to generate all bent functions is by a sieve technique in which many prospective functions are tested.

Direction finding plays a crucial role in various civilian and military applications, related to either radionavigation or radiolocation. Most of the direction finding antennas operate over a wide frequency band, but only a minority of them enable the direction of arrival estimation of an incoming electromagnetic field over a 3-D angular coverage (i.e., estimation of both azimuth and elevation angles). An original approach to obtain a 3-D angular coverageconsists in measuring the six components of the incident electromagnetic field through a so-called vector antenna. The aim of this Ph.D. is to design a passive, compact and wideband vector antenna in order to cover a maximum of applications. Two vector antennas have been designed, manufactured and experimentally characterized. Unlike conventional topology, they enable the measurement of the components of an incoming electromagnetic field thanks to the radiation pattern reconfigurability of an original arrangement of Vivaldi antennas. The first prototype is mounted over a finite metallic support and enables the direction of arrival estimation of vertically-polarized electromagnetic fields over a 1.69:1 bandwidth while the second one can be used regardless of the polarization of the incoming electromagnetic fields over a 8:1 bandwidth. Moreover, the direction finding performances of these vector antennas have been improved in terms of estimation accuracy, sensitivity, robustness to angular ambiguity and polarization mismatch by synthesizing new radiation patterns in the estimation process. A method based onthe Cramer-Rao lower bound has been proposed to select efficiently and rapidly the additional radiation patterns. ; La radiogoniométrie joue un rôle crucial dans diverses applications, aussi bien civiles que militaires, liées soit à la radionavigation ou à la radiolocalisation. La plupart des antennes de goniométrie opèrent sur une large bande de fréquences, mais seule une minorité d'entre elles permettent l'estimation de la direction d'arrivée d'un champ ...

Direction finding plays a crucial role in various civilian and military applications, related to either radionavigation or radiolocation. Most of the direction finding antennas operate over a wide frequency band, but only a minority of them enable the direction of arrival estimation of an incoming electromagnetic field over a 3-D angular coverage (i.e., estimation of both azimuth and elevation angles). An original approach to obtain a 3-D angular coverageconsists in measuring the six components of the incident electromagnetic field through a so-called vector antenna. The aim of this Ph.D. is to design a passive, compact and wideband vector antenna in order to cover a maximum of applications. Two vector antennas have been designed, manufactured and experimentally characterized. Unlike conventional topology, they enable the measurement of the components of an incoming electromagnetic field thanks to the radiation pattern reconfigurability of an original arrangement of Vivaldi antennas. The first prototype is mounted over a finite metallic support and enables the direction of arrival estimation of vertically-polarized electromagnetic fields over a 1.69:1 bandwidth while the second one can be used regardless of the polarization of the incoming electromagnetic fields over a 8:1 bandwidth. Moreover, the direction finding performances of these vector antennas have been improved in terms of estimation accuracy, sensitivity, robustness to angular ambiguity and polarization mismatch by synthesizing new radiation patterns in the estimation process. A method based onthe Cramer-Rao lower bound has been proposed to select efficiently and rapidly the additional radiation patterns. ; La radiogoniométrie joue un rôle crucial dans diverses applications, aussi bien civiles que militaires, liées soit à la radionavigation ou à la radiolocalisation. La plupart des antennes de goniométrie opèrent sur une large bande de fréquences, mais seule une minorité d'entre elles permettent l'estimation de la direction d'arrivée d'un champ ...

Direction finding plays a crucial role in various civilian and military applications, related to either radionavigation or radiolocation. Most of the direction finding antennas operate over a wide frequency band, but only a minority of them enable the direction of arrival estimation of an incoming electromagnetic field over a 3-D angular coverage (i.e., estimation of both azimuth and elevation angles). An original approach to obtain a 3-D angular coverageconsists in measuring the six components of the incident electromagnetic field through a so-called vector antenna. The aim of this Ph.D. is to design a passive, compact and wideband vector antenna in order to cover a maximum of applications. Two vector antennas have been designed, manufactured and experimentally characterized. Unlike conventional topology, they enable the measurement of the components of an incoming electromagnetic field thanks to the radiation pattern reconfigurability of an original arrangement of Vivaldi antennas. The first prototype is mounted over a finite metallic support and enables the direction of arrival estimation of vertically-polarized electromagnetic fields over a 1.69:1 bandwidth while the second one can be used regardless of the polarization of the incoming electromagnetic fields over a 8:1 bandwidth. Moreover, the direction finding performances of these vector antennas have been improved in terms of estimation accuracy, sensitivity, robustness to angular ambiguity and polarization mismatch by synthesizing new radiation patterns in the estimation process. A method based onthe Cramer-Rao lower bound has been proposed to select efficiently and rapidly the additional radiation patterns. ; La radiogoniométrie joue un rôle crucial dans diverses applications, aussi bien civiles que militaires, liées soit à la radionavigation ou à la radiolocalisation. La plupart des antennes de goniométrie opèrent sur une large bande de fréquences, mais seule une minorité d'entre elles permettent l'estimation de la direction d'arrivée d'un champ ...

Direction finding plays a crucial role in various civilian and military applications, related to either radionavigation or radiolocation. Most of the direction finding antennas operate over a wide frequency band, but only a minority of them enable the direction of arrival estimation of an incoming electromagnetic field over a 3-D angular coverage (i.e., estimation of both azimuth and elevation angles). An original approach to obtain a 3-D angular coverageconsists in measuring the six components of the incident electromagnetic field through a so-called vector antenna. The aim of this Ph.D. is to design a passive, compact and wideband vector antenna in order to cover a maximum of applications. Two vector antennas have been designed, manufactured and experimentally characterized. Unlike conventional topology, they enable the measurement of the components of an incoming electromagnetic field thanks to the radiation pattern reconfigurability of an original arrangement of Vivaldi antennas. The first prototype is mounted over a finite metallic support and enables the direction of arrival estimation of vertically-polarized electromagnetic fields over a 1.69:1 bandwidth while the second one can be used regardless of the polarization of the incoming electromagnetic fields over a 8:1 bandwidth. Moreover, the direction finding performances of these vector antennas have been improved in terms of estimation accuracy, sensitivity, robustness to angular ambiguity and polarization mismatch by synthesizing new radiation patterns in the estimation process. A method based onthe Cramer-Rao lower bound has been proposed to select efficiently and rapidly the additional radiation patterns. ; La radiogoniométrie joue un rôle crucial dans diverses applications, aussi bien civiles que militaires, liées soit à la radionavigation ou à la radiolocalisation. La plupart des antennes de goniométrie opèrent sur une large bande de fréquences, mais seule une minorité d'entre elles permettent l'estimation de la direction d'arrivée d'un champ ...

<p>Internet of Things (IoT) controlled a reconfigurable antenna with PIN diode switch for modern wireless communication is designed and implemented. Direct contact of biasing network with the antenna is eliminated and the switching unit is manipulated through IoT method. The proposed antenna has ring structures, in which the outer ring connects the inner ring structure through a PIN diode switch. The dimension of the proposed antenna is reported as 50 mm × 50 mm and its prototype has been made-up on epoxy-Fr4 substrate with 1.6 mm thickness. This antenna setup is made to reconfigurable in four bands (4.5 GHz, 3.5 GHz, 2.4 GHz, and 1.8 GHz) through switching provided by IoT device (NodeMCU). The antenna has a good return loss greater than -10dB.In switching state 2 the antenna has a return loss of -30 dB peak is attained at 3.4 GHz of operating frequency. Similarly the gain response of antenna is good in its operating bands of all switching states and obtained a maximum gain of 2.7 dB in 3.5 GHz. Bidirectional radiation pattern is obtained in all switching states of the antenna.</p>

Yes ; Currently, several microwave filter designs contend for use in wireless communications. Among various microstrip filter designs, the reconfigurable planar filter presents more advantages and better prospects for communication applications, being compact in size, light-weight and cost-effective. Tuneable microwave filters can reduce the number of switches between electronic components. This paper presents a review of recent reconfigurable microwave filter designs, specifically on current advances in tuneable filters that involve high-quality factor resonator filters to control frequency, bandwidth and selectivity. The most important materials required for this field are also highlighted and surveyed. In addition, the main references for several types of tuneable microstrip filters are reported, especially related to new design technologies. Topics surveyed include microwave and millimetre wave designs for 4G and 5G applications, which use varactors and MEMSs technologies. ; This project has received funding from the European Union's Horizon 2020 research and innovation programme under grant agreement H2020-MSCA-ITN-2016 SECRET-722424.