Artificial neural network applications in improved noise wave modeling of microwave FETs

Abstract

The structure of the proposed fishbone-shaped antenna with a V-slot for dual-band operation makes it possible to easily design a high-performance dual-band antenna by adjusting the location and number of fishbones on both sides of a basic antenna with a V-slot at the center. This design can be applied to various types of microstripRecently, many different wireless communication companies have been offering services using different frequency bands, and even the same services often use different frequency bands depending on the region in which these services are offered. It has therefore become a trend for a single system to transmit and receive a diversity of band signals. Accordingly, there is a rapidly expanding demand for such dual-band, multi-band, or wide-band antennas [1,2]. In this article, we propose a fishbone-shaped antenna (tentative), as shown in Figure 1, which offers excellent performance and double-resonance frequency tuning by enabling easy current strength adjustment according to the electrical length in the design process of a dual-band microstrip patch antenna. To verify this proposal, a fishbone-shaped microstrip patch antenna with a V-slot was designed, produced, measured, and analyzed. Recently, it was shown that by modifying the slot shape from a U to a truncated V, the angle of the V arm can be used as an additional parameter to further increase the impedance bandwidth to 36.5% [3]. This antenna can be used by both satellite digital multimedia broadcasting (S-DMB), which uses a band between 2.630 and 2.655 GHz [4] for signal transmission such as digital video, audio, and data, and the wireless local area network (WLAN), a radio-frequency-based network that offers a LAN environment without cabling, at a band between 5.125 and 5.325 GHz [5]. DESIGN AND CONSTRUCTIONA dual-band microstrip patch antenna with a V-slot for S-DMB (2.630 -2.655 GHz) and WLAN (5.125-5.325 GHz) was designed in this study to verify that a fishbone-shaped antenna can offer resonance frequency tuning and excellent performance as a dualband microstrip patch antenna. The design followed the standards of S-DMB and WLAN so as to produce a linear polarized wave. It was also ensured that, at a movable frequency band, the voltage standing wave ratio would become less than 2.0, and that an ample gain and beamwidth can be obtained.At first, a basic V-slot antenna was acquired for a simulation, and the thickness of air ( r ϭ 1) as well as the length and angle of the V-slot were varied. The proposed fishbone-shaped design was then added to the V-slot, and the simulation was repeatedly conducted to acquire the level of performance necessary for a dualband antenna, such as frequency bands and gain, etc.The results, as shown in Figure 2, indicate that the optimized design would have a layer of air ( r ϭ 1), whose thickness T is 5 mm between the ground plane and the substrate and that would use a coaxial prove for impedance matching. The design resulted in an antenna 28 mm ϫ 37 mm in size, with a patch whose size and structur...

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