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![3. The parabolic reflector of Hertz's antenna used in experiments of 1888 with waves of li = 66 cm (reproduced from [29]).](profile/Alexander-Nosich/publication/286316847/figure/fig3/AS:580696858955788@1515460328407/The-parabolic-reflector-of-Hertzs-antenna-used-in-experiments-of-1888-with-waves-of-li.png)
3. The parabolic reflector of Hertz's antenna used in experiments of 1888 with waves of li = 66 cm (reproduced from [29]).
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Citations
... One of the first THz waveguides and a set of corresponding components, which worked in the broad frequency band, was developed in the 1960s at the department of receiving and measuring devices of IRE NAS of Ukraine [9], later renamed as quasioptics department. In the heart of developed QO components was so called hollow dielectric beamguide (HDB). ...
... The tooth-like ribbing of inner dielectric surface reduces the effective permittivity to ' ≈ 1.5 and increases the attenuation of high-order modes. The principal mode HE 11 attenuates as D 3 that is a very small loss comparatively to higher order modes The HDB components were developed and experimentally investigated in the wide frequency band (Fig. 2) from 100 GHz to almost 2.5 THz [9]. As sources, the backward wave tubes were used, which work up to 600 GHz. ...
A set of quasioptical (QO) components was developed for designing the THz radio measuring circuits for plasma diagnostics, radar engineering, spectroscopy, non-destructive testing, biomedicine, education, etc. Components and circuits were built on the basis of oversized dielectric-lined low-loss waveguides with hollow core and included attenuators, phase shifters, polarization-plane rotators etc. The working wave was characterized by the plane phase front, linear polarization, and axially symmetric amplitude distribution. The mode field maximum lies on the waveguide axis and field magnitude smoothly falls toward the waveguide walls. Comparatively to other similar components, the outer metal shell provides protection from environmental impact and increases rigidity. Each component can be joined one to another in one circuit using flanges, pins and clamps.
... Alternative QO devices were developed in the 1960s-1980s at the quasioptics department of IRE NAS of Ukraine [7]. Today we use two major kits of QO devices suitable for the low-loss transmission of the short-millimeter and submillimeter waves. ...
... In [20], similar waveguide with elliptic cross-section was analyzed. These works confirmed the main findings of Kuleshov and Yanovsky [7,8]: the principal wave HE 11 displays well-observed self-filtering effect. However the HDB with a ribbed inner dielectric insert (see Fig 1 (b)) has not yet been studied. ...
... We have used the QO devices and components on the basis of HDW with an inner channel diameter of 20 mm. The HDW was designed as a transmission line for millimeter and submillimeter waves (frequency range is 100 GHz-10 THz) in the early 1960s (see [17]- [20]), although applications in optics had been also discussed for a while [21]. It can be considered as both oversized circular hollow metal waveguide (diameter , where is the wavelength) with an inner dielectric lining [22] and a hollow dielectric tube encased into a metal case [17]- [20], [23]. ...
... The HDW was designed as a transmission line for millimeter and submillimeter waves (frequency range is 100 GHz-10 THz) in the early 1960s (see [17]- [20]), although applications in optics had been also discussed for a while [21]. It can be considered as both oversized circular hollow metal waveguide (diameter , where is the wavelength) with an inner dielectric lining [22] and a hollow dielectric tube encased into a metal case [17]- [20], [23]. The relative permittivity of the tube is with normally being around 2 and around 0.1. ...
... Note that this function is very close to a Gaussian function if . Thanks to this feature, a complete set of HDW-based circuit components had been designed using the QO principles [19], [20] and a measuring technique was also developed [23]. It should be noted that when radiating from HDW to the free space, the HE mode is converted into the fundamental Gaussian beam mode, having a beam waist radius [24]. ...
We investigate the carbon fiber reinforced plastics (CFRP) thermal degradation using the polarization-frequency reflectometry (PFR) method in subterahertz frequency range. The setup that realizes the PFR method is developed and includes the sample scanning by a quasi-optical wave beam with various polarizations and frequencies. The CFRP thermal degradation can be detected in the 260 °C–300 °C temperature range using the PFR method confidently enough. Applying full-wave simulation of a plane wave scattering from a CFRP sample with the aid of the integral functional technique, we show that the temperature dependence of the reflection coefficient is due to the change of the CFRP filler permittivity.
... IELECTRIC-LINED hollow metallic waveguides can be considered the second generation of the oversized waveguides developed in 1950s for long distance data transmission [1,2]. They aimed at addressing the absence of self-filtering of the undesired lossy higher order modes (such as the TM 11 mode, which is degenerated with the TE 01 ) of the original oversized waveguides. ...
... Based on microwave technology a whole set of millimeterwave waveguide elements based on oversized Teflon-lined hollow metallic waveguides were developed in the 60s [2,3]. Unfortunately, the cross-sectional-area to wavelength square ratio (S/λ 2 ) of these elements is of few hundreds, which, even though promises very low THz transmission and facilitates the fabrication, precludes them from commercial applications. ...
Silver-coated Teflon hollow waveguides for 0.5-1.5 THz with S/λ2 ∼10-20 are designed, fabricated and measured using a near-field THz time-domain spectroscopy system. Numerical results predict the fundamental band of the waveguide with 38/120 μm thick Teflon wall to be at ∼1.4/0.5 THz. For the waveguide with 120 μm thick inner Teflon wall, the first three bands are observed in transmission spectrum at ∼0.5, ∼0.9 and ∼1.6 THz, and the corresponding field distributions in the waveguide confirm the HE11 mode formation.
... Dielectric-lined cylindrical waveguide were developed for long distance data transmission at millimeter-waves (i.e. 30 -300 GHz) by the Bell Telephone Laboratory and by the Institute of Radio-Engineering and Electronics of the USSR Academy of Science in parallel [1]. However, this research was terminated by the birth of low-loss optical fibers in the 1970s. ...
... The former was led by Western countries and focused on infrared operating frequencies where optical fibers are no longer low-loss [2]. The latter revolved around the USSR plasma research program and were developed in parallel with corrugated waveguides [1]. These new waveguides with inner corrugations has become widely used in microwaves and millimeter-waves both in transmission line [1] and antenna applications [3]. ...
... The latter revolved around the USSR plasma research program and were developed in parallel with corrugated waveguides [1]. These new waveguides with inner corrugations has become widely used in microwaves and millimeter-waves both in transmission line [1] and antenna applications [3]. ...
The modal composition and dispersion of a 80-mm-long 1 μm-thick silver iodide (AgI) coated metallic cylindrical waveguide is unveiled by terahertz (THz) near-field time-domain microscopy. We demonstrate that the coating is not thick enough to develop the low-loss HE11 mode, but may allow a robust discrimination between the TE01 mode and the rest of the modes. The methodology shown here based on near-field time-domain microscopy along with numerical electromagnetic modeling allows comprehensive waveguide mode characterization.
The IEEE Society’s 140th anniversary and the IEEE Antennas and Propagation Society’s 75th anniversary mark significant milestones in their enduring academic and industrial contributions. Notably, there is a discernible rise in demand for high-performance antennas, continually challenging the boundaries of manufacturing techniques. Innovations in manufacturing act as catalysts, propelling researchers and engineers to explore unconventional design paradigms and push modern antenna performance limits. The evolution of printed lens and transmitarray antenna technologies exemplifies collaborative out-of-the-box developments at the intersection of antenna design and manufacturing methods. In this invited review article, we delineate key advancements in lens and transmitarray antenna manufacturing technologies and their consequential impact on antenna design methodologies. Commencing with foundational techniques, such as milling and injection molding, advancing through printed circuit board (PCB) processes, and culminating in the cutting-edge capabilities of 3D printing, this article reviews the chronological progression that significantly enhances the design possibilities and functionality of lens and transmitarray antennas. Ample representative references are provided to facilitate further exploration of research conducted by other researchers.
