Design of a Band Notched Octagonal UWB Microstrip Antenna for Space Communication

A novel design of a single band notched octagonal shaped ultra-wide band (UWB) microstrip patch antenna has been presented in this manuscript. A modified inverted H shaped slot has been introduced on the radiator of the conventional octagonal monopole reference antenna. Due to this novel slot on the patch a band notch characteristics has been observed. The reference antenna radiates in the band 3.1GHz to 37.4GHz within VSWR<2. The modified proposed antenna produce the band 3.1GHz to 35.2GHz within VSWR<2 and a notched band in 6.7GHz to 8.8GHz with negative gain. The maximum realized gain for the proposed antenna has been found as 6.2dBi and total frequency band covers C band to K band. The reference and proposed antenna have been designed in commercially available software HFSS. With respect to the investigation the above said antenna may be suitable for long distance radio communication, space communication, automotive radar and astronomical observation purpose

A miniaturized printed UWB antenna with dual notching for X-b and and aeronautical radio navigation applications

A low cost miniaturized UWB microstrip antenna with dual notched band for X band and aeronautical radio navigation (ARN) is presented in this article. The antenna (19 16×"> 25 mm2) is composed of a half-circular ring as a radiation patch with an incomplete ground plane. The measured results indicate a fractional bandwidth of 112% for 16S11≤-"> 10 dB between 3 to 10.6 GHz. The dual notched band has been achieved by incorporating window shaped microstrip closed ring resonators at the rear surface of the designed structure. The first notch band is centered at 7.5 GHz (7 8.1 GHz) to reject interference with X-band downlink (7.25 to 7.74 GHz) and second band centered at 9.1 GHz (8.6 9.4 GHz) to reject interference with aeronautical radio navigation (ARN) (8.7 to 9.2 GHz). The simulated and measured return loss, radiation pattern, and gain shows good agreement which confirms the applicability of the designed antenna for the intended UWB applications

Конструкція компактної гексагональної несиметричної антени UWB діапазону зі щілинним отвором і двосмуговим (3.5/5.5 ГГц) режектором

У статті описана конструкція компактної несиметричної антени надширокосмугового (UWB) діапазону з двома смуговими режекторними характеристиками. Ефект режекторних смуг надзвичайно важливий для будь-якої UWB системи, щоб уникнути перешкод існуючим вузькосмуговим додаткам, таким як WiMAX та WLAN. У запропонованій конструкції розглядався випромінюючий елемент шестикутної форми. Дві неоднакові U-подібні щілини на випромінювальному патчі були реалізовані для досягнення характеристик подвійного режекторного фільтра. Перевернута U-подібна щілина витравлювалася на гексагональному патчі для досягнення режекторних характеристик для смуги WiMAX (3,2-3,8 ГГц). Ще одна щілина, що має U-подібну форму, також була вигравірувана на патчі, щоб досягти режекторних характеристик для смуги WLAN (5,1-5,8 ГГц). Запропонована антена має загальний розмір 38×56 мм2. Arlon AD300, який має діелектричну проникність εr = 3, був обраний як матеріал підкладки. Товщина підкладки h = 1,524 мм. Програмне забезпечення для повнохвильового електромагнітного моделювання Ansys HFSS було використано для аналізу радіаційних характеристик конструкції. Запропонована антена успішно охоплює виділений частотний UWB спектр, працюючи в смузі частот від 2,6 ГГц до 11,4 ГГц (VSWR < 2), що відповідає смузі пропускання 120 %. Спроектована антена демонструє гарні коефіцієнти підсилення та двонаправлені діаграми спрямованості.A design of compact ultra-wideband (UWB) monopole antenna with dual band-notched characteristics has been reported in this article. The band-notch effect is extremely important for any UWB system to avoid interference with existing narrowband applications such as WiMAX and WLAN. A hexagonal-shaped radiating element has been considered in this design. Two unequal U-shaped slots on the radiating patch have been implemented to achieve dual band-notched filter characteristics. An inverted U-shaped slot has been etched out on the hexagonal patch to achieve band-notch attributes for WiMAX (3.2-3.8 GHz) band. Another slot of having a U-shape has also been engraved on the patch to attain a notched band for WLAN (5.1-5.8 GHz) band. The proposed antenna having a total dimension of 38× 56 mm2. Arlon AD300 has been chosen as the substrate which has dielectric permittivity εr = 3. The height of the substrate is h = 1.524 mm. Full-wave electromagnetic simulation software Ansys HFSS has been used to analyze the radiation characteristics of the structure. The proposed antenna successfully covers the FCC allocated UWB frequency spectrum by operating over the frequency band between 2.6 GHz to 11.4 GHz (VSWR < 2) which depicts the bandwidth of 120 %. The designed antenna exhibits good gain and bidirectional radiation patterns

One-Pot Synthesis of Novel 2-Imino-5-Arylidine-Thiazolidine Analogues and Evaluation of Their Anti-Proliferative Activity against MCF7 Breast Cancer Cell Line

An efficient surface-mediated synthetic method to facilitate access to a novel class of thiazolidines is described. The rationale behind the design of the targeted thiazolidines was to prepare stable thiazolidine analogues and evaluate their anti-proliferative activity against a breast cancer cell line (MCF7). Most of the synthesized analogues exhibited increased potency ranging from 2&ndash;15-fold higher compared to the standard reference, cisplatin. The most active thiazolidines contain a halogenated or electron withdrawing group attached to the N-phenyl ring of exocyclic 2-imino group. However, combination of the two substituents did not enhance the activity. The anti-proliferative activity was measured in terms of IC50 values using an MTT assay