In this article, a coplanar inverted-F antenna with an electronically controlled ground slot enabling reconfigurability is proposed. Initially a quarter wavelength coplanar inverted-F radiator is designed to operate at 900 MHz. To minimize its size, the radiator is folded to occupy an area of about 10 × 40mm2. Next, a ground slot is introduced to excite another resonance at around 1850 MHz with...

satellite thermal control ensures safe operating temperature ranges for satellite components throughout the mission life. effects of altitude, spin, and position of satellite radiator(s) on the thermal control of a small low earth orbit (leo) satellite have been studied. results show that change in satellite altitude, in the range considered here, does not produce critical thermal conditions. h...

This paper proposes a single circular radiator with multi-port (SRMP) antenna that can estimate the direction-of-arrival (DoA) in azimuth and elevation directions. The proposed SRMP is designed to minimize size of ultra-wideband system by using only one patch radiator. To verify feasibility, fabricated, reflection coefficient boresight gain are measured (-13.3 dB 3.4 dBi at 8 GHz). Then, observ...

This research proposes a compact indirect slot-fed wideband patch array antenna for missile seeker application. The proposed single consists of three dielectric layers radiator, an air substrate-integrated waveguide (SIW) cavity, and feeding network. rectangular is used as radiator on the first substrate layer, SIW cavity (ASIWC) employed to obtain high directivity low mutual coupling character...

In this study, we implement attosecond afterburners in an ultrashort soft X-ray free-electron laser (FEL) to improve the performance of generating pulses. scheme, FEL pulse produced normal radiator section is dumped while well bunched electron beam reserved and reused downstream afterburners. Subsequently, radiation gains rapidly as bunching factor current spike large, making much shorter clean...

In this paper, a frequency reconfigurable, conformal, durable, optically transparent, and unidirectional antenna design is demonstrated for the first time. design, continuous tuning achieved by integrating varactor diode in folded dipole radiator, which backed water-filled reflector to produce radiation pattern mimicking characteristics of microstrip patch antennas. The radiating component expl...

A finite-difference time-domain (FDTD) numerical analysis is used to demonstrate that a toroidal solenoid, coaxial with an electric dipole, is a remarkable nonradiating configuration. It can be used to measure the dielectric permittivity of any ambient matter. It becomes a directional radiator at an interface between two dielectric media, depositing energy in the material with the highest polar...