An ongoing challenge in electrical engineering is the design of antennas whose size is small compared to the broadcast wavelength λ. One difficulty is that the radiation resistance of a small antenna is small compared to that of the typical transmission lines that feed the antenna, so that much of the power in the feed line is reflected off the antenna rather than radiated unless a matching net...

Anisotropic dielectric response occurs naturally due to the presence of gradation, like in functionally graded materials or graded biological cells. However, these materials with locally anisotropic dielectric responses can have macroscopically isotropic responses. In treating graded particles of anisotropic materials, traditional isotropic gradation methods need to be modified. In this work, w...

Close agreement between the measured and predicted insertion loss between dipole antennas above a conducting ground plane has produced a calculable standard dipole antenna. Antenna factors of dipole antennas in the frequency range 30 MHz to 500 MHz have been determined to an uncertainty of 0.1 dB. Though the design of the dipole is not new, the key achievements are: the use of a large standard ...

the possibility of terahertz generation has been investigated from a photoconductive switch based on gaas, gated by a femtosecond laser. the emission properties of photoconductive antenna (pca) with low-temperature-grown (lt) gaas have been studied. in such gaas materials presence of the charged defects induces a redistribution of the electric field between the antenna electrodes. this effect h...

1. Abstract In this design, the dual band dipole antenna feed network with wide bandwidth tapered microstrip balun is studied. The design and experimental results of low profile embedded microstrip dipole antenna with tapered microstrip balun shows fairly good performances. The feed network of the design with wider bandwidth and lower power loss tapered microstrip line to overlap coplanar strip...

─ A novel loop-loaded printed dipole (LLPD) with a wideband balun structure is presented for aiming a dual-band antenna operation at 3.0/5.5 GHz bands. The proposed balun structure alone demonstrates VSWR<1.5 performance over a 3:1 bandwidth. As the loop elements placed on the antenna aperture provides dual-band operation with at least 15% impedance bandwidths, the wideband balun/feed allows fo...

In this paper, we propose low-loss and broadband terahertz (THz) waveguide-to-coupled microstrip transitions using dipole antenna with directors. The simulation and measurement show that insertion/return loss and bandwidth of the waveguide transition can be improved by adding two directors to the basic dipole antenna. The fabricated transition with two directors on a 50 μm-thick quartz substrat...

Electrically small antennas are needed to further lower the cost of wireless elements. However, the antenna gain is constrained to the Harrington limit, while the impedance matching and directivity characteristics deteriorate in electrically small antennas. Using a dipole antenna loaded with a left-handed ladder structure is a promising technique for reducing the size of antennas. In this lette...

In this paper, a numerical model of rectangular enclosure with apertures and a real receiving dipole antenna is considered for the purpose of accurate electric shielding effectiveness calculation. Dipole antenna is often used in practice to measure the level of electromagnetic field at some points inside the enclosure in order to estimate its shielding efficiency. Transmission-line matrix (TLM)...

─ This paper deals with an impact of receiving antenna placed in a metal enclosure on an electromagnetic field distribution within the enclosure, and thus on its shielding effectiveness. In an experimental setup, a frequently used tool for measuring the electromagnetic field level at certain points within the enclosure is a dipole antenna connected to a measuring instrument via a coaxial cable....