A compact microstrip six-port reflectometer (SPR) with extended bandwidth is proposed in this paper. The design is based on using 16-dB multi-section coupled line directional couplers and a multi-section 3-dB Wilkinson power divider operating from 1 to 6 GHz. The proposed SPR employs only two calibration standards: a matched load and an open load. As compared to other dielectric substrates, fabricating the proposed SPR involves using a low-cost (FR4) substrate. A novel algorithm is also proposed to estimate the complex reflection coefficient over the frequency ranges at which the standard performance of the circuit components is not fully satisfied. The new algorithm is based on the circles’ intersection points, which have been derived from basic SPR equations, to estimate the complex reflection coefficient. To validate the SPR performance, a multiband microstrip patch antenna has been measured and the resulted reflection coefficient is compared with those obtained using a vector network analyzer (VNA). Results show that the proposed SPR provides a good estimation of the complex reflection coefficient within the frequency range of 1 GHz to 8 GHz. Owing to its compact size and ease of fabrication, the proposed reflectometer is suitable for various microwave broadband applications.
One of the prominent goals of Metrical Phonology Theory is providing stress of poetry on the syllable-, the foot-, and the phonological word- levels. Analysing poetry is one of the most prominent and controversial issues for the involved number and types of syllables, feet, and meters are stable in poetry compared to other literary texts. The prosodic seeds of the theory have been planted by Firth (1948) in English, while in Arabic يديهارفلا in the second half of the eighth century (A.D.) has done so. Investigating the metrical structure of poetry has been conducted in various languages, whereas scrutinising the metrical structure of English and Arabic poetry has received little attention. This study aims at capturing the
... Show MoreDue to the importance of nanotechnology because of its features and applications in various fields, it has become the focus of attention of the world and researchers. In this study, the concept of nanotechnology and nanomaterials was identified, the most important methods of preparing them, as well as the preparation techniques and the most important devices used in their characterization.
The research problem is to determine the nature of the historical relationship between the profession of social work and volunteer work. Consequently, the research aims to investigate the nature of this relationship from a socio-historical perspective. Three axes have been used to analyze this relationship: the role of voluntary work in the development of the social work as a profession, the efforts made by social work to reach professionism and to distinguish it from voluntary work, and the relationship between social work and voluntary work. The research is qualitative analytical research and adopts the Mixed Methods Research (MMR). It identifies some literature for the analysis and implementation of a scoping process. It represents a
... Show MoreThis review is concluded of 8-Hydroxyquinline (8HQ) compound and derivatives which has a very significant interests with a strong fluorescence , furthermore the relationship between divalent metal ions and characteristic of chelating . In the same way coordinated features have increase of its organic action and inorganic behavior by giving many samples of compounds which are a good chelating agents ligands with more capable of forming very stable complexes.Therefore, the role of (8HQ) is not limited on complexes only but its applications in different fields so this review will focus on demonstration preparation methods and properties of (8HQ) derivatives with their complexes and applications, hopefully that we will cover a part of scientifi
... Show MoreVascular patterns were seen to be a probable identification characteristic of the biometric system. Since then, many studies have investigated and proposed different techniques which exploited this feature and used it for the identification and verification purposes. The conventional biometric features like the iris, fingerprints and face recognition have been thoroughly investigated, however, during the past few years, finger vein patterns have been recognized as a reliable biometric feature. This study discusses the application of the vein biometric system. Though the vein pattern can be a very appealing topic of research, there are many challenges in this field and some improvements need to be carried out. Here, the researchers reviewed
... Show MoreIbn al-Haytham is the pioneer of optics, which is a science that had described optics circumstances. Optics or landscape science as it was known by the Arab and Muslim scientists at the time when is a science known as the conditions of sighters in their quantity and quality as the proximity and distance from the beholder , the different forms , conditions and what mediate between the beholder and the microscopes , to explain useful knowledge of what obscures the sight of the conditions of sighters and is used to measure the space Distant criminality and mirrors.
Ibn al-Haitham wrote his famous book The Book of Mirrors and studied mistakes adopted the m
... Show MoreOne of the prominent goals of Metrical Phonology Theory is providing stress of poetry on the syllable-, the foot-, and the phonological word- levels. Analysing poetry is one of the most prominent and controversial issues for the involved number and types of syllables, feet, and meters are stable in poetry compared to other literary texts. The prosodic seeds of the theory have been planted by Firth (1948) in English, while in Arabic يديهارفلا in the second half of the eighth century (A.D.) has done so. Investigating the metrical structure of poetry has been conducted in various languages, whereas scrutinising the metrical structure of English and Arabic poetry has received little attention. This study aims at capturing the
... Show MoreDBN Rashid, Asian Quarterly: An International Journal of Contemporary Issue, 2018