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This research article examines a L‐shaped dielectrically modulated label free TFET (L‐DM‐TFET) biosensor for the purpose of detecting different biomolecules using a label‐free biosensing detection technique. The proposed structure allows for the recognition of biomolecules by modulating various electrical properties, such as the drain current, transconductance, and linearity parameters. The source region of the proposed TFET incorporates a SiGe (source)/Si (channel) heterojunction, utilizing a low bandgap material of SiGe. This heterojunction is employed to enhance the ON‐state current of the devices. The materials used and the fabrication steps involved in our proposed device are compatible with complementary metal‐oxide‐semiconductor (CMOS) technology. This analysis is conducted using a calibrated Silvaco technology computer‐aided design (TCAD) simulator. Additionally, by considering a dielectric constant range of 1–12, we calculate various figure of merits (FOMs) parameters for the device. These include evaluation of linearity, sensitivity, and noise characteristics. Furthermore, we have conducted an analysis of linearity FOMs, such as VIP2, VIP3, IIP3, and IMD3 for the proposed device under study. Additionally, the linearity analysis of the presented tunneling FET (TFET) indicates the device's excellent performance in distortionless switching operations. Consequently, the L‐shaped dielectrically modulated biosensor holds potential suitability for high‐speed circuit designs. [ABSTRACT FROM AUTHOR]

A compact MIMO antenna with enhanced isolation and the ability to switch the frequency bands is an attractive candidate for the current multifunctional high-speed portable wireless devices. To achieve this objective, a simple and novel compact dual-mode 4-port MIMO configuration for WiMAX and WLAN standards has been introduced in this work. The compactness of the MIMO geometry (34 mm × 34 mm) is due to compact switchable curve-shaped monopoles arranged closely over a loop-shaped continuous ground plane. The ground plane is defected by etching open-ended slots to suppress the surface current flow between the elements. As antenna elements switch between mode-1 (WiMAX band) and mode-2 (WLAN band), the DGS slots are also switchable to enhance isolation across both bands. The switchable DGS slots function as bandstop filters and thus isolate the elements by 40 and 41 dB in the accomplished frequency bands. The intented MIMO antenna reports a − 10 dB return loss bandwidths of 400 MHz (3.3–3.7 GHz) and 1100 MHz (4.75–5.85 GHz) in mode-1 and mode-2, respectively. The diversity metrics of envelope correlation coefficient < 0.002, diversity gain ≈ 10 dB, total active reflection coefficient < − 10 dB, and channel capacity loss < 0.4 b/s/Hz, ensure excellent diversity/MIMO performance. The optimized 4-port MIMO configuration is fabricated, and measured results are compared with the simulated ones to validate the introduced technique. The MIMO antenna's compact form factor and excellent antenna/diversity characteristics confirm its potentiality for use in portable multifunctional wireless devices. [ABSTRACT FROM AUTHOR]

In the wireless cellular network, location management is one of the intricate dynamic issues that expend the available limited wireless resources in order to guarantee for delivering a call to the mobile device. Towards enhancing the Quality of Service and reducing the dilemma of location management, an improved location update scheme has been proposed in this paper to capture the daily behavioral pattern of the mobile users. Here a profile based LU scheme has been developed according to the mobility pattern of the individual users in a cellular network. Especially, mobile phone data is recorded in a Call Data Record (CDR) data base containing the spatial–temporal information of the millions of anonymized users for consecutive 2 months. In this paper, the proposed profile based LU technique takes into consideration of the individual user movement to optimize the location update characteristics in order to minimize the signaling cost of mobile network. The proposed algorithm shows an improvement of 17% in terms of bandwidth compared to the conventional technique. The use of CDR data for profiling the users, the mathematical formulation which has not yet been used by the other researchers and validation of the algorithm based on actual user data rather than theoretically predicted data are the novelty of this work. [ABSTRACT FROM AUTHOR]

This work substantiates the impact of Gaussian doping on the electrical performance of double gate junctionless field-effect transistor (DG-JLFET). To get a better understanding of the influence of non-uniform doping, the device is compared with uniform-doped DG-JLFET with various concentrations. The device is later used to demonstrate its usability in six-transistor static random access memory (6T SRAM) bitcell by studying the performance metrics, i.e. stability noise margin and write delay. A comparison of performance metrics is also given with uniformly doped DG-JLFET-based-6T SRAM. Improvement in static noise margin was observed with Gaussian doping without compromising with write access time. [ABSTRACT FROM AUTHOR]

Inverse artificial neural network (IANN) modeling is used to synthesize a metamaterial unit cell. The ANN approach is best suited to capture the mapping relation between inputs and outputs given a training dataset. In this work, the IANN method is applied to synthesize a metamaterial unit cell for which the inverse model is ill conditioned. A perfectly trained ANN is capable of generating the input data for a desired set of outputs for a fixed set of synaptic weights. In this work, a prior knowledge based input with difference (PKI-D) method is used to perform the inverse mapping. Although the split-ring resonator (SRR) is widely used to realize metamaterials for different applications, no closed-form formula is available to determine its design parameters. The goal of this work is to determine the dimensions of a SRR for a desired frequency and permeability value. The work is carried out in two phases. In the first phase, the inverse model is developed to estimate a single design parameter, then in the second phase, a multiple-parameter estimation model is developed. The average error for the PKI-D model is found to be 0.059. Backpropagation is used to train (solve) the input vector for unknown parameters. [ABSTRACT FROM AUTHOR]

We propose a computer-aided design (CAD) model for synthesis of the unit cell of a metamaterial with the aim of improving the performance of a microstrip antenna designed for use in a traffic collision avoidance system (TCAS). Synthesis of electromagnetic (EM) devices generally requires great computational resources because of their inherent properties, e.g., being complex, nonconvex, and continuous. However, techniques based on soft computing are much more convenient for problems related to such EM devices. In this work, CAD models based on a genetic algorithm and differential evolution are first developed to synthesize a rectangular patch antenna with a microstrip feed line. Transmission line method (TLM) analysis is then used to develop the proposed CAD model for a microstrip patch antenna. In the proposed CAD models, the input parameters are the design/operating frequency, the thickness of the substrate used, and the permeability (μ ) of the substrate material, whereas the outputs are the dimensions of the structural design of the radiating patch and the microstrip feed line. The CST MWS EM tool is also used to design the antenna and validate the parameters of the synthesized antenna. A comparison between the two CAD models is presented. After the successful design of the CAD model for the microstrip antenna, the metamaterial synthesis technique is applied. Then, a metamaterial lens is designed with the help of the proposed CAD model and used to improve the performance of an antenna for use in TCAS applications. A comparison of the performance improvement is given in tabular form towards the end of the paper, including both the simulated and measured results. [ABSTRACT FROM AUTHOR]

A new technique for the calculation of the permeability of an Omega unit cell is presented. In the proposed method, neuro-space mapping is used to transform the Omega unit cell structure to a split-ring resonator (SRR) structure using a functional link artificial neural network (FLANN), taking the dimensions of the Omega unit cell as the inputs and giving the dimensions of the equivalent SRR as the output. The permeability of the Omega-shaped SRR is then calculated using a formula derived by the Lorentz method with these mapped dimensions. The functional linked artificial neural network-space mapping technique is then used to find an SRR equivalent to the Omega unit cell. In the SM part, the FLANN is used as the coarse model and the CST engine as the fine model. The permeability of the Omega unit cell and the SRR match well over the range of 3.5 GHz to 6 GHz when using a learning rate of 0.002 and a tolerance value < 0.05. [ABSTRACT FROM AUTHOR]

Aircraft/traffic alert and collision avoidance system (ACAS/TCAS) is an airborne system which is designed to provide the service as a last defense equipment for avoiding mid-air collisions between the aircraft. In the existing system, four monopole stub-elements are used as ACAS directional antenna and one blade type element is used as ACAS omnidirectional antenna. The existing ACAS antenna has some drawbacks such as low gain, large beamwidth, frequency and beam tuning/scanning issues etc. Antenna issues like unwanted signals reception may create difficulties to identify the possible threats. In this paper, the focus is on the design and development of a unit element microstrip antenna which can be used for ACAS application and to overcome the possible limitations associated with the existing techniques. Two proposed antenna models are presented here, which are single feed and dual feed microstrip dual patch slotted antenna. These are designed and simulated in CST Microwave Studio tool. The performance and other antenna characteristics have been explored from the simulation results followed by the antenna fabrication and measurement. A good reflection coefficient, Voltage Standing Wave Ratio (VSWR), narrow beamwidth, perfect directional radiation pattern, high gain and directivity make this proposed antenna a good candidate for this application. [ABSTRACT FROM AUTHOR]

In this paper, we systematically examined the impact of fin height ( H\mathrm{ Fin} ) and fin angle ( \theta \mathrm{ Fin} ) on the ac performance parameters including total gate capacitance ( C\mathrm{ gg} ), RC delay ( C_{\mathrm{ gg}}V_{\mathrm{ DD}}/I_{\mathrm{\scriptscriptstyle ON}} ), cutoff frequency ( f_{T} ), energy ( E ), total power ( P_{\mathrm{ Total}} ), and leakage power ( P_{\mathrm{ Leakage}} ) of hybrid FinFETs at the supply voltage, V\mathrm{ DD} with on-current I\mathrm{\scriptscriptstyle ON} . The RC delay, energy, and total power consumption are the primary factors limiting the operating frequency of the high-performance devices. Therefore, these electrical parameters are needed to be addressed in the architectural level of the fin based devices. In this paper, a calibrated numerical device simulation tool is used to achieve the best device performances of 14-nm hybrid FinFETs. From the simulated current–voltage ( I – V ) and capacitance–voltage ( C – C\mathrm{ gg}V\mathrm{ DD}/I\mathrm{\scriptscriptstyle ON} , fT , CV2, P\mathrm{ Total} , and P\mathrm{ Leakage} are extracted to analyze the effect of H\mathrm{ Fin} and \theta \mathrm{ Fin} on the performance matrices of these devices. In addition, this paper proposes an optimum structural configuration for 14-nm hybrid FinFET architecture for digital application perspective. [ABSTRACT FROM AUTHOR]

In recent years, wavelet packet (WP) transform has been used as an important speech representation tool. WP‐based acoustic features have found to be more effective than the short‐time Fourier transform (STFT)‐based features to capture the information of unvoiced phoneme in continuous speech. However, wavelet features fail to carry the same usefulness to represent the voiced phonemes such as vowels, nasals. This paper proposes new WP sub‐band‐based features by taking care of harmonic information of voiced speech signal. It has been noted that most of the voiced energy of the speech signal lies in between 250 and 2000 Hz. Thus, the proposed technique emphasises the individual sub‐band harmonic energy up to 2 kHz. The speech signal is decomposed into 16 wavelet sub‐bands and harmonic energy features are combined with WP cepstral (WPCC) features to enhance the performance of voiced phoneme recogniser. A standard phonetically balanced Hindi database is taken to analyse the performance of the proposed feature set. The noisy phoneme recognition task is also carried out to study the robustness. Significant improvement is obtained with the proposed feature set in voiced phoneme recognition over WPCC and conventional Mel frequency cepstral coefficient. [ABSTRACT FROM AUTHOR]

A novel compact triband coplanar waveguide fed metamaterial antenna is proposed. The left-handed (LH) inductance is provided by two parallel short ended spiral inductors. We achieved pentamodes of resonance consisting of negative modes, zeroth mode and positive modes. The resonance frequency at each of these modes are f-2=1.01 GHz, f-1=2.11GHz, f0=2.48 GHz, f+1= 3.04 GHz and f+2=3.54GHz with triband functionality obtained at f-2, f0 and f+2 resonances. Gain of the proposed structure at f-2 f0 and f+2 resonances is found to be -3.4993dB, 1.559dB and 1.9515dB respectively. The proposed antenna is measured at Antenna Measurement Facility (AMF) and results were compared with the simulated results. A good agreement between the measured and the simulated results validates the proposed design. The antenna radiates omni-directional waves in the horizontal plane. The proposed antenna serves the criteria for modern multiband wireless applications with an additional feature of increased bandwidth at the zeroth mode. The proposed multiband antenna is suitable for wireless communication applications such as the Global System for Mobile Communications (GSM) 900 in 1.01GHz, Wireless Local Area Network (WLAN) in the 2.48 GHz band (2.459 - 2.4924)GHz of IEEE 802.1 lb/g ISM band and worldwide interoperability for microwave access (WiMax) standards in the 3.54GHz band (3.491-3.596)GHz of IEEE 802.11a. This proposed antenna is most suitable for precise multiband wireless communication systems which include the mobile and wireless local area network (WLAN) systems due to their large service area. [ABSTRACT FROM AUTHOR]