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This manuscript proposes a high-power terahertz source that consists on a large amount of coherently driven photomixing THz sources. Each element is placed in the gap of a bow tie antenna. The resulting array defines a chessboard-like layout which maximize the density of devices. This novel concept is validated through full-wave simulations. Experimental considerations are also provided for a prototype...
This manuscript proposes the combination of several photomixing THz sources for overcoming the power limitations of this technology. Each element is placed in the gap of a balanced antenna. All the elements conform a 2D rectangular array. For avoiding issues related to having out-of-focus sources when using one electrically large silicon lens, two different strategies are considered: increasing the...
In this paper, a proof-of-concept sub-THz detector for its use in radio telescopes is presented. The detector is intended to work at room-temperature and to be suitable for cosmic microwave background B-mode polarization measurements, so a high sensitivity photon-countig receiver is required. The proposed detector is a practical arrangement of several receivers, each one working on the principle of...
In this paper, a general scheme for a sub-THz photon counting receiver working at room temperature is presented. Its working principle is based on nonlinear up-conversion of the sub-THz signal into the optical domain. For that, a lithium niobate (LiNbO3) WGM resonator is used in a double-resonant configuration. This system has theoretically shown capabilities towards photon counting. The concept is...
in this contribution, the use of Dielectric Rod Waveguide antennas in the millimeter-wave range is studied. They can be used in array configurations for both increasing the gain and electronic beam steering. A 4×4 elements array is manufactured as a proof-of-concept. This topology can be used as a cost-affordable alternative to dielectric lenses for photomixer-based terahertz sources. The use on such...
in this contribution, a new room-temperature terahertz source is proposed for overcoming the power limitations inherent to photomixer-based generators. Specifically, a manufactured vertical “large area emitters” is described and analyzed by proposing a Hertzian dipole array model. An estimation of its radiation pattern is included and will be compared with experimental measurements.
In this contribution, the combination of Dielectric Rod Waveguide DRW antennas with photomixer-based sources in the terahertz range is studied. They are a cost-affordable and more compact alternative to dielectric lenses, which makes them especially appealing for arrays configurations, either for increasing the generated power or for beam steering applications. DRW antennas are limited in band, since...
Arrays of coherently driven photomixers with antenna (antenna emitter arrays, AEAs) have been evaluated as a possibility to overcome the power limitations of individual conventional photomixers with antenna (“antenna emitters”, AEs) for the generation of CW THz radiation. In this paper “large area emitters” (LAEs) are proposed as an alternative approach. In this antenna-free new scheme of photomixing,...
In this contribution, the use of Dielectric Rod Waveguide antennas integrated with a THz photomixer-based emitter is studied. This topology presents a cost-affordable alternative to dielectric lenses for reducing losses caused by scattering into the substrate and reflection in the semiconductor-air interface. For increasing the bandwidth, the use of planar dielectric lens embedded into the rod is...
A dielectric rod waveguide (DRW) made of high-dielectric-constant material such as sapphire, GaAs or Si has in the past been shown to have low transmission loss and good matching with a rectangular metal waveguide at millimetre wavelengths. Also various passive components have been demonstrated. Recently, it has been demonstrated that a single DRW antenna works well over several rectangular waveguide...
In this manuscript, we present a new antenna topology applied to the so called THz gap, based on using a dielectric rod antenna avoiding the use of the classical lens for collimating the emitted/received power. The scope and future perspective of the manuscript is beyond this idea: we develop this topology with the perspective of being the optimum antenna system to be coupled in a THz waveguide easy...
Two different approaches for implementing the LO for a radioastronomy receiver for pumping signal up to 1 THz are presented. The devices are based on photoconductive mixers. An array of 7 pixels is presented and studied. Two different antenna topologies are presented for increasing the power emitted. One is based on the concept of the matching conjugate between the device and the antenna. The second...
Two new topology that potentially can open new solutions for covering the new VLBI2010 configuration and its frequency bands associated are presented in this manuscript. In the first approach three bands are covered: 2.2 – 2.7 GHz, 7 – 9 GHz and 28 – 33 GHz. This new topology is based on an archimedean spiral on the top of two frequency selective surfaces (FSS's) and a ground plane. The architecture...
We discuss two different approaches to overcome the power limitations of CW THz generation imposed to conventional photomixers. The increase in power achievable by using arrays of AEs is studied. Then “large area emitters” are proposed as an alternate approach to overcome the power limitations. In this antenna-free new scheme of photomixing, the THz radiation originates directly from the acceleration...
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