A dual-band single-feed switched beam antenna for WLAN

This article presents the dual-band of a single patch antenna that can operate at a frequency of 2.47 to 5.04 GHz, which is available in WLANs (IEEE 802.11). The beam pattern of the antenna can be switched by changing the position of shorted-circuit points at each edge of the antenna. The advantage of the proposed antenna is that it is a simple structure which is small in size, weighs little and has an easily adjustable beam. In addition, the antenna is tested under real circumstances using the existing WLAN infrastructure. The results confirm that the signal strength can be improved when the proposed switched beam antenna is utilized

A Dual-Band Single-Feed Switched Beam Antenna for WLAN

This article presents the dual-band of a single patch antenna that can operate at a frequency of 2.47 to 5.04 GHz, which is available in WLANs (IEEE 802.11). The beam pattern of the antenna can be switched by changing the position of shorted-circuit points at each edge of the antenna. The advantage of the proposed antenna is that it is a simple structure which is small in size, weighs little and has an easily adjustable beam. In addition, the antenna is tested under real circumstances using the existing WLAN infrastructure. The results confirm that the signal strength can be improved when the proposed switched beam antenna is utilized

A single element of multiband switched beam antenna for 5G applications

This work proposes a simple design of switched beam antenna on square split-ring resonator to operate in multiband frequencies. The antenna is designed to support fifth generation (5G) wireless applications. The proposed antenna provides two different of the main beams, 45˚/225˚±5˚ and 135˚/315˚±5˚, by shorted circuit at 4 different edges. The designed antenna can support nine frequency bands, 7.071, 9.006, 9.321, 9.906, 10.428, 10.718, 12.967, 13.057 and 14.469 GHz, which are the high-band of 5G spectrum when shorted circuit to the ground conductor. The antenna provides maximum gain of 6.41 dBi. The dimension of the antenna is 6×6 mm2 which the thickness of 1.73 mm. The proposed design is based on a simple beam switching antenna configuration, compact size and low-cost manufacturing

Přepínač osmimístný analogový pro 4 vodiče, připojitelný k PC prostřednictvím RS 232 : Analýza řešení a návrh

Import 20/04/2006Prezenční výpůjčkaFakulta elektrotechnická VŠB (Ostrava). Katedra elektroniky (454

Avirulence (AVR) gene-based diagnosis complements existing pathogen surveillance tools for effective deployment of resistance (R) genes against rice blast disease

Avirulence (AVR) genes in Magnaporthe oryzae, the fungal pathogen that causes the devastating rice blast disease, have been documented to be major targets subject to mutations to avoid recognition by resistance (R) genes. In this study, an AVR-gene-based diagnosis tool for determining the virulence spectrum of a rice blast pathogen population was developed and validated. A set of 77 single-spore field isolates was subjected to pathotype analysis using differential lines, each containing a single R gene, and classified into 20 virulent pathotypes, except for 4 isolates that lost pathogenicity. In all, 10 differential lines showed low frequency (95%), inferring the effectiveness of R genes present in the respective differential lines. In addition, the haplotypes of seven AVR genes were determined by polymerase chain reaction amplification and sequencing, if applicable. The calculated frequency of different AVR genes displayed significant variations in the population. AVRPiz-t and AVR-Pii were detected in 100 and 84.9% of the isolates, respectively. Five AVR genes such as AVR-Pik-D (20.5%) and AVR-Pik-E (1.4%), AVRPiz-t (2.7%), AVR-Pita (0%), AVR-Pia (0%), and AVR1-CO39 (0%) displayed low or even zero frequency. The frequency of AVR genes correlated almost perfectly with the resistance frequency of the cognate R genes in differential lines, except for International Rice Research Institute-bred blast-resistant lines IRBLzt-T, IRBLta-K1, and IRBLkp-K60. Both genetic analysis and molecular marker validation revealed an additional R gene, most likely Pi19 or its allele, in these three differential lines. This can explain the spuriously higher resistance frequency of each target R gene based on conventional pathotyping. This study demonstrates that AVR-gene-based diagnosis provides a precise, R-gene-specific, and differential line-free assessment method that can be used for determining the virulence spectrum of a rice blast pathogen population and for predicting the effectiveness of target R genes in rice varieties

Optimalizace odběrů a sazeb ze sítí NN u odběratelů kategorie MOO, MOP

Import 20/04/2006Prezenční výpůjčkaVŠB - Technická univerzita Ostrava. Fakulta elektrotechniky a informatiky. Katedra (451) elektroenergetik