A wideband nanoribbon graphene-based antenna with double rectangular rings for terahertz (THz) applications is presented. The and efficient on physical parameters developed in this paper. has a wide impedance bandwidth of 26% at the center frequency 1 THz, minimum return loss equal to 24 dB average radiation efficiency approximately 44% obtained. An gain 2.45 achieved operational band. goal paper provide an capabilities being wideband, re-configurable simple single-layer structure THz communication.

Abstract In this paper, a microstrip dual-band bandpass filter (DBBPF) based on an octagonal loop resonator (OLR), tapered resonators and open bended stubs (OBSs) is designed analysed. The proposed structure produces two passbands with the centre frequencies of 3.65 5.67 GHz. marked advantages are as follows: Two can be individually tuned. bandwidth upper passband also controlled. Furthermore, DBBPF benefits from ultra-wide stopband 5.9 up to 21 GHz attenuation level higher than 20 dB small...

Recent developments in man--machine interaction have motivated researchers to recognize human emotion from speech signals. In this study, we propose using nonlinear dynamics features (NLDs) for recognition. NLDs are extracted the geometrical properties of reconstructed phase space The traditional prosodic and spectral also used as a benchmark. Fisher discriminant ratio acts filter remove irrelevant quickly. Then wrapper method based on genetic algorithm support vector machine is employed...

This paper analyzes the performance of an energy detector for single and diversity antenna receptions. It starts by providing closed-form expressions to a class semi-infinite integrals which include generalized Marcum Q-function its extension, Nuttal as special cases. Based on these unified frameworks, novel analytical are firstly derived average detection probability over Nakagami-m fading channels. The analysis is subsequently extended cases with receptions including maximal ratio...

Abstract A highly sensitive absorption-based sensor based on folded split-ring metamaterial graphene resonators (FSRMGRs) is designed, and its biomedical application in terahertz (THz) spectrum investigated. The has a nearly perfect absorption with spectral coefficient of 99.75% at 4 THz, high Q -factor (average) 13.76. resonance peak frequency to the refractive index (RI) test medium (analyte) fairly sensitivity 851 GHz/RIU been obtained. specifications can be tuned by an external DC-bias...

In this paper, a switchable antenna with capability to operate in ultrawideband (UWB) frequency from 3 10.7 GHz two notch bands of 3.3–3.7 and 3.7–4.2 GHz, is presented for cognitive radio (CR) multiband orthogonal frequency-division multiplexing (MB-OFDM) applications. The proposed has simple structure compact size 17 × 24 mm 2 . the UWB characteristics obtained using circular radiator patch an embedded T-slot on rectangular parasitic element that attached patch. reconfigurability also...

We derive a comprehensive analytical framework for the ED over generalized, extreme, and non-linear fading conditions which addresses topic completely. This is carried out both conventional diversity receptions it based on area under ROC curve (AUC), an efficient performance measure that widely used in physical sciences engineering. differentiates considered methodology from aforementioned routine approaches additionally provides generic results arbitrary derivatives of MGF useful...

In this paper, sensing performance of an energy detector (ED) for local and collaborative detection scenarios is investigated in unreliable environments dominated by multipath fading shadowing effects. The channel modeled using K <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">G</sub> distribution Nakagami-m lognormal shadowing. Novel analytical expressions are firstly derived the average probability both fading/shadowing cases. analysis then...

Abstract One of the common methods to detect Loss Excitation (LOE) is impedance‐based technique. But it too slow, and may show incorrect performance when faced with power system disturbances like stable swings (SPS). To improve aforementioned problems, a new index introduced based on change transient states synchronous generator which are estimated by Extended Kalman filter (EKF). The principal idea proposed method that angle between voltage q‐axis internal phasor will be increasing during...

Energy detection constitutes a popular sensing approach thanks to its relatively satisfactory performance at low complexity requirements. Its efficiency can be practically enhanced by employing diversity schemes which are also capable of providing adequate mitigation multipath fading effects. Based on this, the present work is devoted analysis energy based spectrum over generalized channels using square law combining. Unlike traditional evaluation receiver operating characteristic (ROC)...

Cognitive radio is regulated to permit efficient access leftover licensed bands by unlicensed users in an opportunistic manner. Spectrum sensing aimed protect the primary from interferences of secondary users. Energy detection constitutes most dominant method for spectrum cognitive and many other systems owing its non-coherent structure as well simplicity applicability. The capability wireless detectors unreliable environments challenged adverse effects multipath fading. Motivated this,...