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This article represents a microstrip line–fed novel circular monopole antenna with ultra‐wideband (UWB) characteristics. The compact antenna provides reconfigurable notches at WLAN (5.2/5.8 GHz) and Wi‐MAX (5.5 GHz) frequency bands. The band rejection is achieved by etching an open‐ended L‐shaped slot in the ground plane, which effectively mitigates the interference between WLAN, Wi‐MAX, and UWB systems with an effective patch area of 36.26%. The proposed antenna operates from 3.05 to 12.11 GHz with VSWR 2 except at stopband (3.89‐5.93 GHz) to filter the WLAN and Wi‐MAX signals. The simulated return loss, gain, and radiation pattern of the proposed antenna has been experimentally verified with the fabricated one which holds a good agreement.  相似文献   
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Herein, a Conductor Backed Co-Planar Waveguide fed, compact, slotted Multiple–Input–Multiple–Output or MIMO antenna having Super Wideband (SWB) response and tunable band-notching feature is presented. In addition, an improved method for cut-off frequency prediction of the antenna is formulated. A super wide frequency response from 01.21 to 34.0 GHz and notches at Wireless Local Area Networks or WLAN bands (04.92–05.83 GHz) and Worldwide Inter-operability for Microwave Access or WiMAX bands (03.30 GHz–03.70 GHz) are obtained. By fine tuning the dimensions of the Split Ring Resonator Structure introduced in the radiating element, band-notched characteristics centered at 05.50 GHz WLAN band is obtained. A second band notch having centre frequency at 03.50 GHz for the WiMAX band is obtained by the introduction of a Spiral Microstrip Defected Structure in the feeding segment. The antenna is 20?×?36?×?1 mm3 in dimension. Acceptable gain all through the functional bandwidth, excepting the notched bands makes the MIMO antenna a novel contender for SWB operations particularly for Wireless Personal Communications.

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3.
Wireless Personal Communications - This paper presents the design and development of a livestock tracking system, with the objective of transmitting the location and activity status of the animals,...  相似文献   
4.
An H‐shaped dielectric resonator array antenna is presented for wideband applications. The proposed antenna is excited by slot feed mechanism and investigated experimentally. The antenna covers the frequency ranges from 1.41 to 2.59 GHz, and 4.73 to 6.06 GHz with the corresponding impedance bandwidth of 59% and 24.65%, respectively. The simulation results fulfill the bandwidth requirements of IEEE 802.11a/b/g (2.4‐2.484 GHz/5.15‐5.35 GHz/5.725‐5.825 GHz) for Wireless local area network (WLAN) applications. The proposed antenna has simple structure, easy to fabricate and its measured radiation pattern shows a reliable performance in the desired operating bands.  相似文献   
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The MIMO-OFDM increases spectral efficiency without the use of channel state information (CSI). However, the bit error rate (BER) in the MIMO-OFDM model increases dramatically due to the increase in nonlinear distortion in the power amplifier (PA). In this research, a novel pre-coder integrated MIMO-OFDM technology is designed for effective BER reduction, and its performance is analyzed. The discrete wavelet-based OFDM system is one of the key ideas to present good orthogonal by emphasizing orthogonal wavelets. It helps to mitigate inter-symbol interference (ISI) and noise within the channel by extending the bandwidth (BW) compared to conventional OFDM systems. But, DWT-OFDM highly suffered due to downsampling, which degrades system efficiency. To overcome this, a redundant discrete wavelet transform (RDWT) is proposed in this article to enhance spectral efficiency. For modulation, 16-bit quadrature amplitude modulation (QAM) is introduced in this work. In addition to this, a block bi-diagonalization (BBD) pre-coder technique is proposed to mitigate unwanted noise and interference in the MIMO-OFDM system. The performance measures such as ergodic sum capacity, BER, throughput, average jitter noise power, mean square error (MSE), and power consumption are analyzed using the MATLAB platform. The proposed method obtains the ergodic sum capacity of 6.25 bps/Hz, a BER of 0.021, a throughput of 95.2%, MSE of −0.47, and a power consumption of 1.15 μW. The simulative results prove the efficacy of the proposed method.  相似文献   
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This article introduces a super wideband along with three notch bands circular patch monopole antenna. The design structure is applicable for microwave and high-speed wireless devices (2.19 to 25 GHz). In order to create a broad band, a ring dimension circular patch is used. To generate three notch bands, six symmetrical tiny cylinder stubs are introduced on the ground. These notch band frequencies can eliminate unwanted interference from various wireless frequencies, which mainly cover three notch bands: 5.5–7.3, 12.05–14.46, and 17.71–19.5 GHz. The steady radiation, super bandwidth, and stable gain properties expand when the ring patch and line feed are combined. It is excellent for many UWB applications because of its compact size (39 × 29 mm 2) and large bandwidth (166.97% fractional bandwidth). This model employs various size reduction and matching approaches to get a better response. The mechanisms of these structures are identified, and overall performance is compared with parametric analysis, tables, and figure.  相似文献   
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