A double-discone antenna for an ultra-wideband frequency scan is presented. An exquisite assembly of two inverse-feeding discone antennas shows a 30:1 broad bandwidth with VSWR below 2.5 and an omnidirectional radiation pattern. These features make the proposed antenna very suitable for both the UWB system antenna and the wideband scan antenna. © 2004 Wiley Periodicals, Inc. Microwave Opt Techn...

Several wideband antennas are presented for either wireless application. This paper presents the performance of a simple monopole antenna loaded with an annular dielectric resonator as a wideband transmitting/receiving antenna. By adjusting the length of the monopole and load arm, a 10-dB bandwidth of 94% is achieved while maintaining monopole-like radiation pattern, which covers UWB applicatio...

Log-periodic array antennas have been investigated over a long period of time, the reason for the same being its provision of a constant radiation performance and good reflection coefficient performance over a wide frequency band, which can be considered as an important characteristic of this type of antennas. It created a high impact on development of new generation antennas with advanced feat...

The scaling factor in a ultra-wideband antenna is investigated. Here is showed that the lower frequency limit of the bandwidth is reduced as the scaling factor is bigger than unity. Using the obtained results a UWB planar monopole antenna was designed. The measured antenna bandwidth goes from 650 MHz to 20 GHz for a VSWR ≤ 2. The radiation pattern remains almost omnidirectional. The radiator us...

Airborne ultra wideband (UWB) impulse-radiating antennas (IRAs) present an especially large radar cross section to X–band radar. To mitigate this problem, we have numerically and experimentally investigated the use of a frequency selective surface (FSS) as a broadband filter to reflect X–band radar while transmitting lower-frequency UWB signals without loss or dispersion. We present here result...

Low-profile, compact and easily integrated body worn antennas are the essence of efficient, reliable and user-friendly body-centric networks. The paper presents different planar printed ultra wideband (UWB) antennas and their applications as part of on-body communication systems. Both frequency and time domain characteristics of the proposed antennas are investigated and analysed. The paper emp...

Ultra-wideband (UWB) radio offers low power consumption, low power spectral density, high immunity against interference, and other benefits, not only for consumer electronics, but also for medical devices. A cochlear implant (CI) is an electronic hearing apparatus, requiring a wireless link through human tissue. In this paper we propose an UWB link for a data rate of 1.2Mbps and a propagation d...

This paper presents an effective modeling methodology for Ultra-wideband (UWB) antennas. The methodology is based on augmenting an existing narrow-band model with a macro-model while simultaneously perturbing component values of the narrow-band model. The narrow-band model is an empirical-based circuit and the macro-model described by rational functions is determined using data fitting approach...

In traditional approaches to antenna characterisation, spectral and angular dispersion are modelled separately. In the paper, the dependence of the power radiated from ultra wideband (UWB) antennas jointly on frequency and direction is established experimentally. It is demonstrated that both omni-directional and directional antennas typically exhibit higher directivity with frequency, with the ...

On February 14, 2002, the Federal Communications Commission (FCC) of the United States adopted the First Report and Order that permitted the commercial operation of ultra wideband (UWB) technology (FCC, 2002). The FCC allocated a bandwidth of 7.5GHz, i.e. from 3.1GHz to 10.6GHz, to unlicensed use for UWB applications. Ultra Wideband is defined as any communication technology that occupies great...