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Gain standards for accurate antenna measurements are expensive due to their extensive calibration procedure. This paper presents a concept for low cost antennas that comprise of sheets of FR-4 which are accurately manufactured using modern CNC technology. This accuracy in turn will render the calibration procedures unnecessary. The impact of tolerances is studied to determine whether the concept is...
Antenna miniaturization techniques using meander line and Near-field Resonant Parasitic (NFRP) are presented in this paper. Also, antenna performance including reflection loss and gain have been optimized during the scale-down process. The proposed antennas are compared with the theoretical limits of small antennas to confirm the optimized performance in a limited space. The smallest possible size...
This paper proposes a new approach to reduce weight and complexity of VHF/UHF cubesat antennas by utilizing a dual band antenna, rather than standard two-antenna system routinely implemented in cubesats. Three systems are compared: A standard system with separate transmit/receive dipoles, a dual-band dipole for both transmit and receive and a dual-band monopole, which uses the body of 1U cubesat (10...
In order to achieve lightweight yet low cost antennas for use in a geostationary space environment, the GeReLEO-SMART project develops a substrate-based, multilayer antenna structure which can replace traditional horn antennas as feeds for reflector antennas. To verify a design, an example mission is developed, consisting of a 2×2 patch antenna array with an integrated stripline bandpass filter. The...
This paper presents an efficient, systematic approach to design a set of antenna demonstrators. The process and its building blocks are explained as well as a short overview on two examples of antenna arrays is given.
The paper proposes a new method for private point-to-point communication. It employs a monopulse antenna system, where the summary beam is used to transmit the useful signal to the intended receiver, while the differential beam is used to generate noise, in order to bury the signal for angles other than boresight. The method is tested using simulated QPSK modulation, providing a beamwidth with bit...
Large deployable antennas (LDA) are an upcoming technique used as space borne reflector antennas. Low stow volume and mass are one of the key advantages allowing big reflector diameters to be launched on conventional vehicles. A primary concern in reflector antenna building is surface accuracy, especially at high operating frequencies. Conventional LDA use sophisticated high cost mechanics to deploy...
This paper proposes a reconfigured horn antenna with reduced side-lobe radiation by using electromagnetic band gap (EBG) structure. A mushroom-like structure with a circular-shaped patch as unit cell is designed to achieve a complete EBG. The EBG structure is lined on the metal wall along the E-plane of the horn antenna. This causes the surface waves on the metal wall to be suppressed, resulting in...
For microwave circuits and planar antennas, complex multilayer structures pose a challenge for the designer since different materials for substrates, bonding films and coating have different frequency behaviour. Furthermore, the traditional measurement techniques for the complex permittivity rely on different field distributions than those of a transmission line making it hard to account for non-isotropic...
Analyses on the diameter of the ground plane of helical antennas show that, when the diameter of this plane is slightly smaller than the one of the helix itself, backfire radiation is achieved. Considering this ground plane as a director, the addition of more ground planes - or directors - is proven to increase the directivity of the antenna. With these reduced ground planes not causing any blockage...
Analyses on the diameter of the ground plane of helical antennas show that, when the diameter of this plane is slightly smaller than the one of the helix itself, backfire radiation is achieved. Considering this ground plane as a director, the addition of more ground planes - or directors - is proven to increase the directivity of the antenna. With these reduced ground planes not causing any blockage...
RF substrates based on PTFE are often used in high frequency space circuits. As they are mounted inside of an enclosure, the body of the satellite and the housing absorbs space radiation. However, patch antennas in space applications impede shielding of the active substrate area resulting in the exposure of the PTFE substrate to high dose space radiation. This paper shows the results of a measurement...
The GeReLEO-SMART project aims to build a communication experiment to be launched on the German technology demonstration mission “Heinrich-Hertz” (H2SAT). On its geostationary orbit it will demonstrate new space appropriate technology of a 26 GHz patch antenna array with integrated low noise amplifiers (LNA), MEMS switching of the RF signal and FPGA mission control. The antenna consists of a multi-layer...
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