This paper presents a gain improvement of dual-band antenna for 2.45/5.5 GHz WLAN applications. The radiating element of the proposed antenna consists of a circular disc monopole with circular-slot laid on FR-4 substrate and backed by a partial ground plane. This partial ground plane is modified to improve its radiation performance. This proposed antenna operates over the frequencies of 2.4-2.485 GHz and 5.15- 5.825 GHz with nice radiation characteristics and magnitude of S11 better than -10 dB. An EM simulator has been used in the design and simulation. In addition, an experimental validation was set and measured to compare with the simulated results. All numerical results will be reported and discussed in the paper.
Słowa kluczowe: gain improvement; dual-band antenna; circular monopole antenna; WLAN applications.
W artykule opisano dwupasmową antenę do pasma2.45/5.5 GHz I sici WLAN. Antena składa się z okrągłego dysku i okrągłej szczeliny. Częściowo uziemione podłpoże poprawia właściuwości radiacyjne.
Keywords: dwupasmowa antena, sieci bezprzewodowe, okrągły promiennik
With Rapid developments of modern wireless communications, various microwave technologies have been utilized for different applications, which make the microwave spectrum more crowded. Wireless fidelity has transformed in to the standard for wireless local area network (WLAN) communications in the 2.45 and 5.5 GHz ISM bands, with the frequency ranges from 2.4 to 2.485 GHz as well as 5.150-5.350 GHz, 5.470-5.725 GHz, and 5.725-5.850 GHz . For system flexibility and feasibility, antennas that are capable to serve in both of the specified operation bands are highly attracted. For this reason, dualantennas are promoted to overwhelm the 2.45- and 5.5 GHz WLAN bands -. A dual-band antenna can be usually accomplished by utilizing two types of singlefrequency antennas for each band , and taking a dualfrequency antenna for two separate bands , . For the two types of single-frequency antennas, two external feeding networks must be come up with these individual dual-band antennas, which probably entail some structural sophisticates into applications -. As mentioned above, an element to make up a dualband antenna is more suitable to employ a dual-frequency antenna. There are many techniques to design for WLAN dual-band, such as using quarter-wavelength resonant slots in different shapes, coplanar fed, parasitic elements, and defected ground plane -. Latterly, many researchers adopt an attention on printed slot antennas (PSA), since wide-slot antennas have two orthogonal resonance modes, which are combined to form a wide impedance bandwidth . As reported for increasing impedance bandwidth, antennas with various shapes like circle, ellipse, and triangle were introduced . In our previous work , we presented the design and implementation of dual band with partial ground plane (PGP); nonetheless, its gain is not high. Hence, a technique to enhance the radiation performance of a microstrip-fed ci [...]
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