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Item type:Item, Optimized Gaussian Pulse Design for UWB System Using Particle Swarm Optimization Based-on Generalized Bessel Polynomials(2022-01-01) ;Chutchavong, Vanvisa ;Anuwongpinit, Thanavit ;Purahong, Boonchana ;Archevapanich, TuanjaiJanchitrapongvej, KanokThe ultrawideband system operates a very short pulse with enormous bandwidth to provide high data rates for data transmission. To design the UWB pulse, considering the pulse shape is very necessary, and a spectral emission mask of the designed pulse should meet the FCC spectral mask requirement between frequency range 3.1 GHz to 10.6 GHz. The traditional UWB pulse design is based on the Gaussian derivative. However, the frequency spectrum is not satisfied the FCC spectral mask requirement. In this study, the Gaussian pulse can be designed from the mathematical characteristic of the generalized Bessel polynomial. The spectral efficiency of the proposed pulse can be improved by the combination of the derivative of Gaussian pulse with a weight coefficient optimization with particle swarm optimization (PSO). PSO is a population-based optimization algorithm inspired by animal behavior. PSO is applied with generalized Bessel polynomial transfer function to gain the best weight coefficient, we proposed to optimize its weight vector to design a pulse that exceeds to FCC spectral mask. The results were found in MATLAB software show that generalized Bessel polynomials can approximate the proposed pulse with combination method and PSO. The spectral efficiency is improved to 89.30% and the spectrum is greater close to the FCC spectral mask requirement. To confirm an improved spectral efficiency compared to the previous works. - Some of the metrics are blocked by yourconsent settings
Item type:Item, Ultra-wideband slot antenna on flexible substrate for WLAN/WiMAX/UWB Applications(2014-01-01) ;Archevapanich, Tuanjai ;Lertwatechakul, Mayuree ;Rakluea, Paitoon ;Anantrasirichai, NoppinChutchavong, VanvisaAn ultra-wideband slot antenna on flexible substrate is designed to support a wide range of wireless communication systems. The antenna is a rectangular slot antenna fed by microstrip line with conductor strip and tuning stub on flexible substrate (Mylar Polyester film). The rectangular slot is etched out from the ground plane with conductor strip in the slot, and the other plane contains a microstrip line with tuning stub. The proposed antenna’s effective frequency range covers overall standard bands of WLAN, WiMAX, and UWB. The antenna was simulated and analyzed by using IE3D Zeland software [1]. And the simulation results presents the characteristics of the antenna in terms of bandwidth return loss, VSWR, and radiation patterns. - Some of the metrics are blocked by yourconsent settings
Item type:Item, Rectangular slot antenna with Asymmetrical conductor strip for bandwidth enhancement coverage UWB standard(2014-01-01) ;Archevapanich, Tuanjai ;Rakluea, Paitoon ;Anantrasirichai, Noppin ;Purahong, BoonchanaChutchavong, VanvisaThis paper presents the bandwidth enhancement of rectangular slot antenna fed by microstrip line on the flexible Mylar Polyester film substrate. Asymmetrical conductor strip is designed and inserted in the rectangular slot to extend the bandwidth from 3.06 GHz to 7.2 GHz frequency range. Besides, the rectangular conductor at the end of the feeding microstrip line is introduced for increasing the bandwidth at high frequency up to 12.32 GHz. This improved antenna to cover standard frequency range of UWB (3.1 GHz – 10.6 GHz). Finally, as to reject the frequency band of IEEE 802.11a (5.15 GHz – 5.35 GHz), the line strip at the side of tuning stub is added. In this case, the band-notched frequency from 5.15GHz to 5.38 GHz can be easily obtained.
