Abstract: This paper presents the design of a microstrip line fed irregular hexagonal shaped monopole antenna. The antenna consists of a sliced semi-circular ground plane with a square slit below the feed line which exhibits an Ultra Wide Band (UWB) of 7.5GHz. A frequency notch band (5.1GHz -5.57GHz) is obtained by introducing 'U' shaped slot on to the proposed antenna. The proposed monopole is fabricated, measured for reflection coefficient, radiation pattern and peak gain to validate the performance of the antenna.

The dielectric resonator antenna (DRA) has revolutionized the latest generation of communication systems with their obvious advantages of small size, bandwidth, and power-consuming capabilities. In this paper, an analysis of the impact of the dielectric material on the radiation characteristics of the DRA is presented with simulation reports. The proposed antenna takes the shape of a circular patch with the dielectric resonator having different shapes. This helps to analyze the impact of the tapering adjustments on the features of the antenna. The simulations are performed using the latest version of the complex electromagnetic modeling tool, and results are analyzed in terms of simulated reports like reflection coefficient (S11), voltage standing wave ratio, radiation patterns, and field distribution plots. The overall size of the proposed antenna is 18 × 12 mm². The measured results are in good agreement with the simulation results. The proposed DRA is suitable for mobile wireless applications.

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The Thoracic Electrical Bioimpedance (TEB) helps to determine the stroke volume during cardiac arrest. While measuring cardiac signal it is contaminated with artifacts. The commonly encountered artifacts are Baseline wander (BW) and Muscle artifact (MA), these are physiological and nonstationary. As the nature of these artifacts is random, adaptive filtering is needed than conventional fixed coefficient filtering techniques. To address this, a new block based adaptive learning scheme is proposed to remove artifacts from TEB signals in clinical scenario. The proposed block least mean square (BLMS) algorithm is mathematically normalized with reference to data and error. This normalization leads, block normalized LMS (BNLMS) and block error normalized LMS (BENLMS) algorithms. Various adaptive artifact cancellers are developed in both time and frequency domains and applied on real TEB quantities contaminated with physiological signals. The ability of these techniques is measured by calculating signal to noise ratio improvement (SNRI), Excess Mean Square Error (EMSE), and Misadjustment (M ad ). Among the considered algorithms, the frequency domain version of BENLMS algorithm removes the physiological artifacts effectively then the other counter parts. Hence, this adaptive artifact canceller is suitable for real time applications like wearable, remove health care monitoring units.

The paper presents the idea of defective ground structures for the improvement in the radiation characteristics of the antenna especially in the multi-input multi-output (MIMO) configuration. The proposed antenna model with partially flared out feed system is designed and analyzed with defective ground in both single and array configuration. A T stub is a T shaped stub used in this work with defected ground structure. A T stub is included along with defective ground to enhance the MIMO configuration features. The simulations are carried out on electromagnetic modelling tool and analyzed by measuring the parameters like reflection coefficient, voltage standing wave ratio (VSWR), gain, radiation pattern and current distribution plots. For the fabrication of the proposed antenna these measurements are very important. The antenna is fabricated and validated in terms of S-parameters and VSWR. The proposed results are good agreement with the simulated results. The overall size of the antenna is 24 × 18 x 0.8 mm³.