Si-Bipolar-A Potential Candidate for High-Speed Electronics in 20 and 40 Gb/s TDM Systems?

1997 ◽  
Author(s):  
H.-M. Rein ◽  
E. Gottwald ◽  
T. F. Meister
Keyword(s):  
High Speed ◽  
Potential Candidate

scholarly journals All-optical demultiplexing of closely spaced multimedia radio signals using sub-picometer fiber Bragg grating

2021 ◽  
Author(s):  
Hatice Kosek
Keyword(s):  
Wireless Lan ◽  
High Speed ◽  
Bandpass Filter ◽  
Optical Filters ◽  
Multimedia Data ◽  
Potential Candidate ◽  
Rf Signals ◽  
All Optical ◽  
Radio Signals ◽  
Network Flexibility

Subcarrier multiplexed (SCM) transmission of multimedia radio signals such as CATV (5-860 MHz), cellular wireless (900 MHz) and wireless LAN (2.4 GHz) over fiber is frequently used to deliver broadband services cost effectively. These multi-channel radio-over-fiber (ROF) links have interesting applications and can connect enhanced wireless hotspots that will support high speed wireless LAN services or low speed cellular services to different customers from the same antenna. The SCM signals need to be demultiplexed, preferably in the optical domain for many reasons. Prefiltering of SCM signals with fiber-based optical filters warrants the use of inexpensive photodetectors and increases network flexibility. However, realizing optical demultiplexing as sub-GHz level is challenging and thus necessitates optical filters with high selectivity and low insertion loss and distortion. We developed a novel sub-picometer all-optical bandpass filter by creating a resonance cavity using two closely matched fiber Bragg gratings (FBGs). This filter has a bandwidth of 120 MHz at -3 dB, 360 MHz at -10 dB and 1.5 GHz at -20 dB. Experimental results showed that the filter is capable of separating two radio frequency (RF) signals spaced as close as 50 MHz without significant distortion. When this demultiplexer was employed to optically separate 2.4 GHz and 900 MHz radio signals, it was found to be linear from -38 dBm to +6 dBm with ~ 25.5 dB isolation. There was no significant increment in the BER of the underlying multimedia data. Results verified that the fabricated narrow bandpass filter can be a potential candidate in demultiplexing of RF signals in networks based on subcarrier multiplexed schemes.

scholarly journals All-optical demultiplexing of closely spaced multimedia radio signals using sub-picometer fiber Bragg grating

2021 ◽  
Author(s):  
Hatice Kosek
Keyword(s):  
Wireless Lan ◽  
High Speed ◽  
Bandpass Filter ◽  
Optical Filters ◽  
Multimedia Data ◽  
Potential Candidate ◽  
Rf Signals ◽  
All Optical ◽  
Radio Signals ◽  
Network Flexibility

Subcarrier multiplexed (SCM) transmission of multimedia radio signals such as CATV (5-860 MHz), cellular wireless (900 MHz) and wireless LAN (2.4 GHz) over fiber is frequently used to deliver broadband services cost effectively. These multi-channel radio-over-fiber (ROF) links have interesting applications and can connect enhanced wireless hotspots that will support high speed wireless LAN services or low speed cellular services to different customers from the same antenna. The SCM signals need to be demultiplexed, preferably in the optical domain for many reasons. Prefiltering of SCM signals with fiber-based optical filters warrants the use of inexpensive photodetectors and increases network flexibility. However, realizing optical demultiplexing as sub-GHz level is challenging and thus necessitates optical filters with high selectivity and low insertion loss and distortion. We developed a novel sub-picometer all-optical bandpass filter by creating a resonance cavity using two closely matched fiber Bragg gratings (FBGs). This filter has a bandwidth of 120 MHz at -3 dB, 360 MHz at -10 dB and 1.5 GHz at -20 dB. Experimental results showed that the filter is capable of separating two radio frequency (RF) signals spaced as close as 50 MHz without significant distortion. When this demultiplexer was employed to optically separate 2.4 GHz and 900 MHz radio signals, it was found to be linear from -38 dBm to +6 dBm with ~ 25.5 dB isolation. There was no significant increment in the BER of the underlying multimedia data. Results verified that the fabricated narrow bandpass filter can be a potential candidate in demultiplexing of RF signals in networks based on subcarrier multiplexed schemes.

scholarly journals Applications of Particle Tracking Velocimetry to severe nuclear accident experimentation

2021 ◽  
Vol 1 (1) ◽  
Author(s):  
Michael Johnson ◽  
Christophe Journeau
Keyword(s):  
High Speed ◽  
Dynamic Properties ◽  
Fuel Mixture ◽  
Solid Substrate ◽  
Liquid Sodium ◽  
Potential Candidate ◽  
Video Imaging ◽  
Distinctive Features ◽  
Particle Properties ◽  
Transient Interactions

Experimental research into severe nuclear accidents may entail the discharge of a very high-temperature lava-like molten fuel mixture, corium, either into a pool of less-dense, more-volatile coolant or onto a solid substrate where the corium will spread and cool. In both instances, remote, high-speed video imaging is usually required to interpret these transient interactions and PTV represents a powerful tool for the characterisation of the dynamic properties of discrete melt fragments or distinctive features in the surface of the melt during spreading. Nuclear fuel-coolant interactions present particular challenges for PTV analysis as a molten jet and its fragments can exhibit high rates of inter-frame deformation and undergo fragmentation with a relatively high frequency. A PTV algorithm, adapted to these challenges, is presented whereby a user-defined tolerance in the evolution of certain particle properties is used to refine the potential candidate particles prior to particle matching. This candidate refinement step is used to distinguish between acceptable levels of deformation between successive sightings of a given particle, and more substantial changes consistent with fragmentation or coalescence, requiring the tracking of a new particle. Implementation of the PTV algorithm is presented for (1) an X-ray video from the FCINA-30-1 experiment between a jet of molten stainless steel and liquid sodium, conducted at the JAEA’s MELT facility, and (2) video imaging of the VE-U9-ceramic experiment of a molten corium-thermite mixture spreading on a zirconium substrate, conducted at the CEA’s VULCANO facility. The latter case-study enabled the characterization of > 70,000 local velocity vectors at locations corresponding to distinctive temperature heterogeneities in the surface of the spreading melt, providing extensive insight into the spreading dynamics for the validation of corium spreading models.

scholarly journals Orthogonal interlayer coupling in an all-antiferromagnetic junction

2021 ◽  
Author(s):  
Yongjian Zhou ◽  
Liyang Liao ◽  
Tingwen Guo ◽  
Hua Bai ◽  
Mingkun Zhao ◽  
...  
Keyword(s):  
High Speed ◽  
Giant Magnetoresistance ◽  
Spin Dynamics ◽  
Magnetic Ordering ◽  
Functional Materials ◽  
Interlayer Coupling ◽  
Information Storage ◽  
Stray Field ◽  
Potential Candidate ◽  
Ultrahigh Density

Abstract The interlayer coupling of two ferromagnetic layers results in found of giant magnetoresistance, which forms the foundation of spintronics and accelerates the development of information technology. Compared with ferromagnets, antiferromagnets (AFMs) possess huge potential in ultrafast and high-density data processing and information storage because of their terahertz spin dynamics and subtle stray field. The interlayer coupling in AFMs has long been neglected, because the collinear parallel and antiparallel arrangements of AFMs are indistinguishable. However, the noncollinear interlayer coupling in AFMs is detectable, and can be a potential candidate for practical antiferromagnetic spintronic devices. Here we demonstrate orthogonal interlayer coupling at room temperature in an all-antiferromagnetic junction Fe2O3/Cr2O3/Fe2O3, where the Néel vectors in the top and bottom functional materials Fe2O3 are strongly orthogonally coupled and the coupling strength of which is significantly affected by the thickness of the antiferromagnetic Cr2O3 spacer. From the energy and symmetry analysis, the direct coupling via uniform magnetic ordering is excluded. The coupling is proposed to be mediated by quasi-long range order in the spacer. Besides the fundamental significance, the strong coupling in an antiferromagnetic junction makes it a promising building block for practical antiferromagnetic spintronics with high-speed operation and ultrahigh-density integration.

scholarly journals Experimental Investigation of Zadoff-Chu Matrix Precoding for Visible Light Communication System with OFDM Modulation

2018 ◽  
Vol 2018 ◽  
pp. 1-6
Author(s):  
Xinyue Guo ◽  
Yang Guo ◽  
Shuangshuang Li
Keyword(s):  
Visible Light ◽  
Orthogonal Frequency Division Multiplexing ◽  
High Speed ◽  
Forward Error Correction ◽  
Signal To Noise Ratio ◽  
Light Emitting Diode ◽  
Average Power ◽  
Visible Light Communication ◽  
Potential Candidate ◽  
Ofdm Modulation

Light-emitting diode- (LED-) based visible light communication (VLC) has become a potential candidate for next generation high-speed indoor wireless communication. Due to the limited modulation bandwidth of the LED, orthogonal frequency division multiplexing (OFDM) modulation is particularly preferred in the VLC system to overcome the ISI, which suffers from the high peak-to-average power ratio (PAPR) and leads to severe performance loss. In this paper, we propose and experimentally demonstrate a novel Zadoff-Chu matrix (ZCM) precoding scheme, which can not only reduce the PAPR, but also provide uniform signal-to-noise ratio (SNR) profile. The theoretical analysis and simulation show that the proposed scheme achieves better PAPR performance compared with the traditional precoding schemes. The experimental demonstration further validates the bit error rate (BER) performance improvement, where the measured BERs are all below the 7% pre-forward error correction (pre-FEC) limit of 3.8 × 10−3 when the transmitted data rate is 50 Mb/s.

Experimental investigation on spiked body in hypersonic flow

2008 ◽  
Vol 112 (1136) ◽  
pp. 593-598 ◽  
Author(s):  
R. Kalimuthu ◽  
R. C. Mehta ◽  
E. Rathakrishnan
Keyword(s):  
Drag Reduction ◽  
Hypersonic Flow ◽  
High Speed ◽  
Aerodynamic Drag ◽  
Angle Of Attack ◽  
Leading Edge ◽  
Geometrical Parameters ◽  
Potential Candidate ◽  
Hypersonic Wind Tunnel ◽  
High Speed Vehicle

Abstract A spike attached to a hemispherical body drastically changes its flowfield and influences aerodynamic drag in a hypersonic flow. It is, therefore, a potential candidate for drag reduction of a future high-speed vehicle. The effect of the spike length, shape, spike nose configuration and angle-of-attack on the reduction of the drag is experimentally studied with use of hypersonic wind-tunnel at Mach 6. The effects of geometrical parameters of the spike and angle-of-attack on the aerodynamic coefficient are analysed using schlieren picture and measuring aerodynamic forces. These experiments show that the aerodisk is superior to the aerospike. The aerodisk of appropriate length, diameter and nose configuration may have the capability for the drag reduction. The inclusion of an aero disk at the leading edge of the spike has an advantage for the drag reduction mechanism if it is at an angle-of-attack, however consideration to be given for increased moment resulting from the spike is required.

Numerical simulation of the flow field over conical, disc and flat spiked body at Mach 6

2010 ◽  
Vol 114 (1154) ◽  
pp. 225-236 ◽  
Author(s):  
R. C. Mehta
Keyword(s):  
Flow Field ◽  
Drag Reduction ◽  
High Speed ◽  
Blunt Body ◽  
Stokes Equations ◽  
Aerodynamic Drag ◽  
Dynamic Pressure ◽  
Recirculation Region ◽  
Potential Candidate ◽  
Wave Separation

Abstract A forward facing spike attached to a hemispherical body significantly changes its flow field and influences aerodynamic drag and wall heat flux in a high speed flow. The dynamic pressure in the recirculation area is highly reduced and this leads to the decrease in the aerodynamic drag and heat load on the surface. Consequently, the geometry, that is, the length and shape of the spike, has to be simulated in order to obtain a large conical recirculation region in front of the blunt body to get beneficial drag reduction. It is, therefore, a potential candidate for aerodynamic drag reduction for a future high speed vehicle. Axisymmetric compressible laminar Navier-Stokes equations are solved using a finite volume discretisation in conjunction with a multistage Runge-Kutta time stepping scheme. The effect of the spike length and shape, and the spike nose configuration on the reduction of drag is numerically evaluated at Mach 6 at a zero angle-of-attack. The computed density contours agree well with the schlieren images. Additional modification to the tip of the spike to get different types of flow field such as the formation of a shock wave, separation area and reattachment point are examined. The spike geometries include the conical spike, the flat-disk spike and the hemispherical disk spike of different length to diameter ratios attached to the blunt body.

20-40-Gbit/s-CLASS GaAs MESFET DIGITAL ICs FOR FUTURE OPTICAL FIBER COMMUNICATIONS SYSTEMS

1998 ◽  
Vol 09 (02) ◽  
pp. 399-435 ◽  
Author(s):  
TAIICHI OTSUJI ◽  
KOICHI MURATA ◽  
KOICHI NARAHARA ◽  
KIMIKAZU SANO ◽  
EIICHI SANO ◽  
...  
Keyword(s):  
Circuit Design ◽  
High Speed ◽  
Frequency Conversion ◽  
State Of The Art ◽  
Optical Fiber Communications ◽  
Potential Candidate ◽  
Ic Design ◽  
Gaas Mesfet ◽  
Communications Systems ◽  
Fiber Communications

This paper describes recent advances in high-speed digital IC design technologies based on GaAs MESFETs for future high-speed optical communications systems. We devised new types of a data selector and flip-flops, which are key elements in performing high-speed digital functions (signal multiplexing, decision, demultiplexing, and frequency conversion) in front-end transmitter/receiver systems. Incorporating these circuit design technologies with state-of-the-art 0.12 μm gate-length GaAs MESFET process, we developed a DC-to-44-Gbit/s 2:1 data multiplexer IC, a DC-to 22-Gbit/s static decision IC, and a 20-to-40-Gbit/s dynamic decision IC. The fabricated ICs demonstrated record speed performances for GaAs MESFETs. Although further operating speed margin is still required, the GaAs MESFET is a potential candidate for 20- to 40-Gbit/s class applications.

scholarly journals Review on Millimeter Wave Antennas- Potential Candidate for 5G Enabled Applications

2016 ◽  
Vol 5 (3) ◽  
pp. 98 ◽  
Author(s):  
M. A. Matin
Keyword(s):  
Millimeter Wave ◽  
High Speed ◽  
High Gain ◽  
Potential Candidate ◽  
60 Ghz ◽  
Communication Services ◽  
Low Profile ◽  
Compact Size ◽  
Millimeter Wave Antenna ◽  
On Chip

The millimeter wave (mmWave) band is considered as the potential candidate for high speed communication services in 5G networks due to its huge bandwidth. Moreover, mmWave frequencies lead to miniaturization of RF front end including antennas. In this article, we provide an overview of recent research achievements of millimeter-wave antenna design along with the design considerations for compact antennas and antennas in package/on chip, mostly in the 60 GHz band is described along with their inherent benefits and challenges. A comparative analysis of various designs is also presented. The antennas with wide bandwidth, high-gain, compact size and low profile with easiness of integration in-package or on-chip with other components are required for 5G enabled applications. 

scholarly journals Design and Performance Analysis of Depletion-Mode InSb Quantum-Well Field-Effect Transistor for Logic Applications

2017 ◽  
Vol 05 (02) ◽  
pp. 1750006 ◽  
Author(s):  
R. Islam ◽  
M. M. Uddin ◽  
M. Mofazzal Hossain ◽  
M. A. Matin
Keyword(s):  
Quantum Well ◽  
Field Effect ◽  
High Speed ◽  
Field Effect Transistor ◽  
Short Circuit ◽  
Current Gain ◽  
Potential Candidate ◽  
High Electron ◽  
Well Field ◽  
Effect Transistor

The design of a 1[Formula: see text][Formula: see text]m gate length depletion-mode InSb quantum-well field-effect transistor (QWFET) with a 10[Formula: see text]nm-thick Al2O3 gate dielectric has been optimized using a quantum corrected self-consistent Schrödinger-Poisson (QCSP) and two-dimensional drift-diffusion model. The model predicts a very high electron mobility of 4.42[Formula: see text]m2V[Formula: see text]s[Formula: see text] at [Formula: see text][Formula: see text]V, a small pinch off gate voltage ([Formula: see text]) of [Formula: see text]0.25[Formula: see text]V, a maximum extrinsic transconductance ([Formula: see text]) of [Formula: see text][Formula: see text]4.85[Formula: see text]mS/[Formula: see text]m and a drain current density of more than 3.34[Formula: see text]mA/[Formula: see text]m. A short-circuit current-gain cut-off frequency ([Formula: see text]) of 374[Formula: see text]GHz and a maximum oscillation frequency ([Formula: see text]) of 645[Formula: see text]GHz are predicted for the device. These characteristics make the device a potential candidate for low power, high-speed logic electronic device applications.

Sign in / Sign up

Export Citation Format

Share Document