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In this paper, we describe the development of a new L-band (1.4 GHz) Cryogenic Phased Array Feed (PAF) system, referred to as the GBT2 array. Results from initial measurements made with the GBT2 array are also presented. The PAF was developed for the Green Bank Telescope (GBT) as part of the Focal L-band Array for the GBT (FLAG) project. During the first stage of the development work (Phase I), a...
The aim of this contribution is to discuss the application of a failure detection and sparse recovery technique to a very large isophoric sparse array proposed for satellite communications. Accurate numerical results will show that the sparsity of the source is beneficial to the failure detection process, and a limited number of sensor can be used for the online detection of the failures and correction...
Airframe manufacturers, avionics companies, satellite operators and major airlines have launched programs to develop high speed data services for use on commercial aircraft and business jets. Inmarsat currently supplies aircraft with medium-rate data service and high quality voice throughout the world on both spot-beams and global beams. In 2001 EMS Technologies began installing Inmarsat BGAN transceivers...
We describe a new phased array feed design. The array is composed of elements based on a solid of revolution fed by twin wire transmission lines. An infinite array model is used to simulate the noise performance of the array and this model is compared with a full EM simulation of the finite array and measured noise data. The modelling indicates that this array is an excellent candidate for a phased...
A 6-bit pseudo segmented current-steering digital-to-analog converter (DAC) designed in 40nm low-leakage (LL) CMOS process is presented. The DAC employs 4× time-interleaved (TI) topology which enables sampling rates up to 16GS/s with relatively low clock frequency. A design-for-test on-chip memory with 6bits1-k bytes/bit is programmed with strictly costumed data sequence and read out at 1Gb/s rate,...
This paper presents the latest progress in demonstrating and characterizing the Traveling-Wave Antenna Array (TWAA) as a Multioctave Planar Phased Arrays (MPPA) capable of efficient wide-angle scan over multioctave bandwidth. (Beam Steering Network (BSN) and T/R module are not included here.) Four brass board TWAA panels having 16∗16 array elements were fabricated and tested for wide-angle scan up...
This study reports a novel tight-coupled dipole array antenna to operate with up to six octave bandwidth and 60 degrees scanning. The array was designed through full-wave EM simulations by employing the current sheet array radiator concept that was advanced by a novel integrated feed network. Several prototypes of planar and conformal arrays across 0.3–20 GHz have been fabricated and tested with good...
To describe the structure of news information domain, we introduce the concept of a director, that is a conditional axis, the position of which is defined by averaging the directions of vectors that set the location of all news clusters centroids. To characterise the dynamics of reaching the news event, we introduce the concepts of decreasing and increasing trends of domain varying. The analysis of...
A novel concept for a dual-polarized microstrip antenna array with a center frequency of 23.75 GHz is introduced. The array is composed of ten single square patch elements having equal resonance frequencies in both directions. The microstrip patches are rotated by 45 ° and linearly aligned to obtain a fan beam antenna characteristic. The feed structure is in seriesparallel configuration with best...
This article discusses the problem of measurement of Field Emission Energy Distribution (FEED) from silicon carbide by the retarding potential method. A description of an natural experiment setting is presented as well as a model of its electrophysical system of field emission current differentiation by modulated retarding potential. It discusses problems of implementations of the measurement on a...
An antenna sub-array configuration and the design of the antenna element for a dual-polarized X-band SAR application are presented. The antenna element is based on an aperture-coupled stacked patch that, unlike typical designs, does not include any foam layers. The sub-array including the antenna elements and the feed-network can be realized using currently available multi-layered printed circuit...
This work will present the corrugated-horns, polarizers and ortho-mode transducers developed for the 49-element coherent polarimeter array working in [39, 48] GHz to be embarked in the Large Scale Polarization Explorer. The latter is an ASI-funded balloon experiment designed to measure the CMB B-modes on large angular scales. The presentation will focus on the analysis, design, manufacturing and measurements...
A prototype Mid-Frequency Aperture Array (MFAA), using Vivaldi antennas, was designed. This type of array is a contender for the MFAA of the Square Kilometer Array Phase 2, SKA Mid. The construction was made from scratch and it was low-cost. Sixteen antenna elements, made of aluminium, were erected on a wooden platform. The orientation allows polarization on the E-plane as well as the H-plane. Each...
A planar substrate integrated waveguide slot-fed microstrip grid array antenna for the frequency range 76–81 GHz is presented. The antenna is realized on a standard soft RF substrate. It is fed using a transverse slot in a substrate integrated waveguide on a separate substrate layer below the antenna. A wideband microstrip to substrate integrated waveguide is designed to feed the antenna. Measurement...
In this contribution a dual-band, dual-polarized microstrip antenna is presented. The antenna is designed for ground based Ka-band satellite communications. It relies on a standard multilayer printed circuit board technology to minimize production cost. The antenna size is smaller than half the freespace wavelength at 30GHz enabling its utilization as an array element. The dual-frequency characteristics...
Satellite communication (SatCom) is facing a spectrum scarcity problem due to the limited available exclusive spectrum and the high demand of the broadband satellite services. In this context, there has been an increasing interest in the satellite community to exploit the non- exclusive Ka-band spectrum in order to enhance the spectral efficiency of future broadband satellite systems. Herein, we propose...
The aim of this paper is to design, develop and simulate a linear patch antenna array working at 9.5 GHZ and integrate it on a microwave laminate. First, two rectangular patch antennas, one with a direct feed and the other with an inset feed are designed and compared to each other then 1×8 power divider is designed and simulated. Finally, eight rectangular radiating patches on a low dielectric constant...
X-band folded reflectarray (FRA) antenna is designed and implemented. The proposed FRA provides compactness, reliability, broadband with high efficiency. The reflectarray utilizes multilayer patch cells that receive the waves and twist them from vertical to horizontal polarization with the proper phase. Variable microstrip line lengths control the phases of scattering parameters. The FRA is designed...
The complementary strip-slot element is a broadly-matched microstrip radiator that has been used to design innovative series-fed arrays. It consists of a microstrip series-fed slot that have its complementary stub on the layer of the microstrip and aligned to the slot. In this contribution, the influence of the strip and slot geometry on its performance is studied through the analysis of four different...
The System Assembly and Modelling framework in CST STUDIO SUITE allows the construction of an entire system consisting of antenna (or multiple antennas), matching or feed networks, and the environment at a schematic and three-dimensional level. From this system level description studies can be derived which allow the user to focus on individual stages of the design, e.g. the antenna on feed network...
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