We developed a method for preparing catalysts by using hybrid clustering to form high density of metal/oxide interfacial active sites. A Rh–Mo catalyst was prepared cluster, [(RhCp*)4Mo4O16] (Cp* = η5-C5Me5), as the precursor. The activities toward NO–CO–C3H6–O2 reaction depended on mixing (hybrid > coimpregnation ≈ pristine Rh). also exhibited durability against thermal aging at 1273 K in air....

This paper presents an element of a 2×2-element array antenna for Inmarsat BGAN/GPS applications. The element is an axial mode printed quadrifilar helical antenna that has been integrated with a compact feed network to provide sequential phase rotation for circular polarization (CP) radiation. The novel integrated lumped-element feed network is designed to provide a balanced RF power to the fou...

In Chinese Compass Navigation Satellite System (CNSS for short), dual-band antennas are more attractive, because they can provide both navigation and communication services. In this paper, we present a dual-band dual-circular-polarized planar spiral-slot CNSS antenna. This antenna works at L band (1616± 5MHz, left-handed circular polarization, LHCP) and S band (2492± 5MHz, right-handed circular...

The estimation of the direction electromagnetic (EM) waves from a radio source using electrically short antennas is one challenging problems in field astronomy. In this paper we have developed an algorithm which performs better and polarization estimations than existing algorithms. Our proposed Snapshot Averaged Matrix Pencil Method (SAM) modification to (MPM) based Direction Arrival (DoA) algo...

In this letter, a high-aperture-efficiency (? AP ), right-hand circularly polarized (RHCP), sequentially rotated hexagonal microstrip antenna array, working at GPS L1 band, is proposed. The proposed design placed on the top of floating sensor node for ocean and marine monitoring applications. To...

A two-port dual-circularly polarized (CP), low-profile broadside-radiating electrically small Huygens dipole antenna is presented that has an advanced feed network and multilayer stacked layout of its electric magnetic near-field resonant parasitic (NFRP) elements. It radiates left-hand CP (LHCP) or right-hand (RHCP) fields at 1.5 GHz resonance frequency depending on the selected port. The meas...

The global navigation satellite system-reflectometry (GNSS-R) field has experienced an exponential growth as it is becoming relevant to many applications and captivated the attention of elevated number research scholars, centers companies around world. Primarily based on contents two Special Issues dedicated GNSS-R Earth observation, this review article provides overview latest advances in fiel...

In this paper, linearly and circularly polarized single-layer Substrate Integrated Waveguide (SIW) horn antennas with nearly equal half power beamwidths in principal planes for the 24 GHz ISM band are designed. The uniqueness of solution lies application a pixelated structure to design these SIW antennas. For design, novel heuristic algorithm called Binary Ink Stamp Optimization is proposed. At...

It is well known that directional antennas and circular polarization (CP) antennas are effective in reducing degradations of receiving power caused by multipath propagation effects [1]. Therefore, simultaneous controlling these two features—directivity and polarization—is expected to considerably reduce such adverse effects. Some papers have reported CP antennas with beam steering means [2], [3...