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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]

Abstract Microstrip line based two switchable power dividers are presented in this paper and these models are capable of power division control at four output ports. Here, power switching is implemented with terminating some open-ended stub-lines using varactor diodes and corresponding mathematical equations are derived. Proper DC voltages are applied for biasing the activator diodes and consequently to have appropriate stub-line terminations. For designing these power dividers, CST Microwave Studio is used here as the EM tool. The characteristics such as return loss, insertion loss and isolation have been explored from the simulation results followed by it's fabrication and measurement. Quite good agreement is achieved between the simulation and the experimental results. Much better performance characteristics make this proposed power divider a good candidate for various microwave systems where switchable power dividers are required. [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]

TCAS/ACAS (Traffic/Aircraft Collision Avoidance System) is an airborne system designed to increase cockpit awareness of nearby aircraft and to service as a last defense against mid-air collisions between the aircrafts. In the existing system, four monopole stub elements are used as TCAS directional antenna and one blade type element is used as TCAS Omni-directional antenna. The transmission and reception frequencies of the TCAS antenna are 1.03G Hz and 1.09G Hz respectively. The existing TCAS 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 in identifying the possible threats. In this paper, the focus is on the design and development of a novel Microstrip Antenna Array which can be used for TCAS/ACAS application. Two proposed antenna models are presented here – a Unit Element Dual Feed Microstrip Dual Patch Slotted Antenna and a Compact Microstrip Antenna Array. These are designed in CST tool to meet the current needs of aircraft Collision Avoidance System and to overcome the possible limitations associated with the existing techniques. The performance and other antenna characteristics have been explored from the simulation results followed by the antenna fabrication and measurement. A good Reflection Coefficient and VSWR with proper 50 Ω Impedance Matching, narrow Beamwidth, perfect Directional Radiation Pattern, high Gain and Directivity at the operating frequencies make this proposed antenna a good candidate for TCAS application. The proposed antenna would be expected to meet the requirements of the advanced avionics standards in terms of design simplicity, lightweight and high performance. [ABSTRACT FROM AUTHOR]

In this work, a simple parasitic decoupling structure integrated compact dual-band quad-element Multiple-Input Multiple-Output (MIMO) configuration with improved isolation is proposed for 3.5 and 5.8 GHz bands of Worldwide Interoperability for Microwave Access (WiMAX) and Wireless Local Area Network (WLAN) applications. The lower and higher frequency bands accomplish an impedance bandwidth of 400 MHz (3.35 – 3.75 GHz) and 450 MHz (5.6 – 6.05 GHz), respectively. A slot integrated curve-shaped compact (11 × 20 mm2) dual-band monopole antenna is explored to implement the proposed compact MIMO configuration. A parasitic decoupling structure comprising T and inverted L-shaped thin metal strips is introduced between the orthogonally placed antenna elements. It exhibits dual stopband characteristics to enhance the isolation significantly at the targeted frequency bands despite the compact footprint (34 × 34 mm2) of the MIMO geometry. The optimized decoupling structure improves the isolation between the elements by 31.5 and 32 dB in the lower and higher bands than the MIMO geometry without decoupling elements. The antenna provides good radiation characteristics with peak gains of 4.18 and 3.62 dBi within the bands. The computed diversity metrics, such as envelope correlation coefficient (< 0.01), diversity gain (> 9.93 dB), mean effective gain ratio (-0.13 to 0.16 dB), channel capacity loss (< 0.4 b/s/Hz), and total active reflection coefficient (< -10 dB), ensures good diversity performance. The fair agreement between the simulated results using HFSS EM solver and the measured results on the fabricated prototype validated the proposed MIMO configuration. [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]

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]

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]

The increasing demand for assorted services from extensive wireline and wireless users place a significant burden on the band-limited radio spectrum. To settle the demand, smart reuse and management of the spectrum are necessary. In this contribution, Cognitive Radio being an emerging technology provides a platform to share the same spectrum between Primary Users (licensed) and Secondary Users (unlicensed) for significant improvement in the spectrum efficiency. The coexistence of users for data communications in a band-limited channel calls for a robust congestion controller to maximize throughput. This work presents the design of a robust nonlinear congestion controller based on event-triggered sliding mode for Cognitive Radio Networks. The goal is to maintain desired Quality of Service of the network with optimum bandwidth and resource utilization. The controller has been designed on the notions of sliding mode, better known for its inherent robustness and disturbance rejection capabilities. An event-triggering scheme has been incorporated with the sliding mode for optimum utilization of the available resources. The signal is sampled and control is updated only when a predefined condition gets violated while ensuring acceptable closed-loop behavior of the system. The efficiency of the proposed controllers has been validated using simulations. [ABSTRACT FROM AUTHOR]