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A periodic leaky-wave antenna is reported in substrate integrated nonradiative dielectric waveguide technology. Periodical change of substrate permittivity along the waveguide channel is used to perturb the propagating LSE11 mode. The hosting substrate is perforated following a periodicity to realize the perturbation. Thus, the antenna structure is very easy to implement and suitable for millimeter-wave applications. The antenna scan performance and leakage rate is dependent on the periodicity and size of the perturbation. Guidelines for choice of the parameters along with the condition for radiation of only one beam over the frequency range of interest are discussed. The developed antenna on Alumina substrate shows a good scan performance from −35° to 7° over the frequency range 96 to 108 GHz with a gain better than 10 dBi. [ABSTRACT FROM PUBLISHER]

This communication presents a leaky-wave antenna (LWA) in substrate integrated nonradiative dielectric (SINRD) waveguide. An SINRD waveguide being a periodic structure, the bandwidth of the fast-wave frequency band can be controlled by changing the periodicity of the hole array. As a result, a fast or a slow scanning is possible by appropriate choice of the periodicity without changing the substrate parameters. Leakage characteristics of an SINRD waveguide for different parametric variations are discussed. Measurement results are provided. [ABSTRACT FROM AUTHOR]

The concept of substrated integrated waveguide (SIW)-fed horn and antipodal linearly tapered slot antenna (ALTSA) are jointly used to design a low-cost, high-gain, and efficient planar dielectric-loaded antenna for ultra-wideband gigabyte wireless services, which are demonstrated over E- and W-bands. SIW is used to feed the proposed antenna. To increase the gain of the antenna, a dielectric-loaded slab is used in front of the antenna and works as a dielectric guiding structure. The SIW feed, the proposed antenna, and the loaded dielectric are all integrated in a planar single layer substrate, resulting in low cost and easy fabrication. Low-cost printed circuit board (PCB) process is utilized to fabricate the antenna structure with rectangular and elliptical shaped loaded dielectrics. Measured bandwidth of the antenna covers both E- and W-bands (70–110 GHz). Measured gain of the single-element antenna is \14\pm \0.5 dBi, while the measured radiation efficiency of 84.23% is obtained at 80 GHz. Wideband SIW power dividers are used to form a 1\,\times\,4 array structure. Measured gain of the 1\,\times\,4 array antenna is \19\pm \1 dBi, while the measured radiation pattern and gain are almost constant within the wide bandwidth of the antenna. [ABSTRACT FROM AUTHOR]

A wideband planar dielectric rod antenna with substrate integrated non-radiative dielectric (SINRD) waveguide feed, is presented in this communication for W-band and up-millimeter-wave applications. The antenna and its feeding structure are integrated into a single layer substrate, which decreases the fabrication cost and integration complexity. Simulated and measured results show that the antenna has a wide bandwidth. Due to the structure of the SINRD guide which is shielded on top and bottom of the substrate, the proposed antenna is suitable for multilayer structure techniques such as LTCC or on-chip antenna. This antenna presents numerous features such as broad bandwidth, relatively high and stable gain, use of high dielectric constant substrate, and substrate-oriented end-fire radiation. The proposed antenna is suitable for gigabyte chip-to-chip communications. Measured bandwidth of the antenna is 10 GHz (93–103 GHz) while a relatively flat gain of 9.5 \pm 1~dB is obtained over the bandwidth of interest. [ABSTRACT FROM PUBLISHER]

Significant advances in the development of millimeter-wave and terahertz (30–10 000 GHz) technologies have been made to cope with the increasing interest in this still not fully explored electromagnetic spectrum. The nature of electromagnetic waves over this frequency range is well suited for the development of high-resolution imaging applications, molecular-sensitive spectroscopic devices, and ultrabroadband wireless communications. In this paper, millimeter-wave and terahertz antenna technologies are overviewed including the conventional and nonconventional planar/nonplanar antenna structures based on different platforms. As a promising technological platform, substrate-integrated circuits (SICs) attract more and more attention. Various substrate-integrated waveguide (SIW) schemes and other synthesized guide techniques have been widely employed in the design of antennas and arrays. Different types of substrate-integrated antennas and beamforming networks are discussed with respect to theoretical and experimental results in connection with electrical and mechanical performances. [ABSTRACT FROM PUBLISHER]

A novel six-port network based on half-mode substrate integrated waveguide (HMSIW) is proposed. In this design, a HMSIW hybrid 3 dB coupler and a -90° phase shifter are designed as fundamental building block of six-port network. By combining four HMSIW couplers and one phase shifter, a HMSIW six-port network at 29-32 GHz is constructed. The six-port network is fabricated and measured. Measurement results agree well with simulation, and show good balance and phase relationship between ports. [ABSTRACT FROM AUTHOR]

Computer-aided-design models are developed and used for the characterization of ferroelectric materials at microwave frequencies, which aim at measuring the dielectric properties of BST-0.5 thin films on alumina substrates. Complex dielectric constant, voltage tunability, and K-factor are deter- mined for the ferroelectric materials with a series of BST/alumina coplanar waveguides (CPWs) and interdigital capacitors (IDCs) of different list film thicknesses. Propagation constants are extracted through measurements for CPWs using a multiline thru-reflect-line calibration technique from 1 to 16 GHz. IDC capacitance is measured at different bias points ranging from o to 35 V over the frequency range of 1-10 GHz. Conformal mapping models are deployed to interrelate circuit measurements with the BST film intrinsic properties. Dielectric constants of approximately 500-700 and loss tangents of approximately 0.07 are typically obtained at low frequencies for the BST films investigated in this study. BST voltage tunability is typically 15% at 35 V and 6 6Hz. [ABSTRACT FROM AUTHOR]