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Showing 1 to 19 of 19 for “"VGA"”.
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Design of a High Dynamic Range CMOS Variable Gain Amplifier for Wireless Sensor Networks
… dynamic gain range CMOS variable gain amplifier (VGA). The design adopts a new approximated exponential equation called the pseudo exponential equation to implement the dB-linear function. The proposed VGA is designed to have an extremely wide gain variation, small chip area, low supply voltage, …
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Design of a High Temperature GaN-Based Variable Gain Amplifier for Downhole Communications
… frequency (IF) variable gain amplifier (VGA) for downhole communications, which can operate up to an ambient temperature of 230 °C. The proposed VGA is designed using 0.25 μm GaN on SiC high electron mobility transistor (HEMT) technology. Measured results at 230 °C show that the VGA has a …
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Large Signal HBT Model and Integrated Circuit Design Using 300-Ghz Indium Phosphide HBT Technology
… high-gain and wideband variable gain amplifier (VGA) is developed using a negative-RE approach. This circuit shows a single-ended S21 of 18 dB and a 3-dB bandwidth of 50 GHz, producing a gain-bandwidth product of 397 GHz which is over two times of the value measured from the VGA designed by …
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Linear Analog Front -End Circuits for Fiber -Optic Communication Systems
… wide gain tunability and enhanced linearity. The VGA achieves tunable gain from 2.43 dB to 44.37 dB while being process insensitive; a worst case spurious free dynamic range of 26.46 dB with an output swing of 1.4 Vpp, and minimum 3-dB bandwidth of 6.5 GHz consumes 102 mW of power in a 3.3-V, …
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FPGA Implementation of Blob Recognition
… can achieve the real-time performance of full VGA video processing at 32 frames per second (fps). In addition, this work comes up with a new method called Dual Connected Component Labelling (DCCL) suitable for FPGA implementation.
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A comparison of fixed tube current (FTC) and automatic tube current modulation (ATCM) CT methods for abdominal scanning : implications on radiation dose and image quality
… organs) and a relative visual grading analysis (VGA) method (five different axial images). Image quality evaluation was performed by the researcher after testing agreement between against five different observers. RESULTS: There were no significant differences in the mean radiation doses between …
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LOW POWER AND HIGH SIGNAL TO NOISE RATIO BIO-MEDICAL AFE DESIGN TECHNIQUES
… having any errors. A Variable Gain Amplifier (VGA) is sometimes required to adjust signal amplitude to maintain the dynamic range of the ADC. Also, the Bio-medical transceiver needs an accurate and temperature-independent reference voltage and current for the ADC, commonly known as Bandgap …
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Effets de l'irradiation sur l'arséniure de gallium dopé au silicium de type n : observation optique de la lacune de gallium
… introduit dans le GaAs la lacune de gallium (VGa)et l'impureté du silicium accepteur (SiAs) qui indique le transfert de l'impureté de silicium du site Ga au site As. Nous avons relié la dégradation de la mobilité de Hall dans le GaAs irradié aux neutrons de 1 MeV à l'introduction du VGa et du …
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LOW-COST STRUCTURED-LIGHT 3D CAPTURE SYSTEM DESIGN
… We augment this hardware with two 3M MPro 150 VGA (640×480) pocket projectors. We also describe an analytical approach to predicting the achievable resolution of the reconstructed 3D object based on differentials and small signal theory, and an experimental procedure for validating that the …
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Analog Signal Processing Elements for Energy-Constrained Platforms
… are demonstrated in a Variable-Gain Amplfier (VGA) to compress large differential inputs into small single-ended outputs suitable for processing by other analog elements. Finally, a novel circuit composed of only six transistors is proposed to compute the continuous-time derivative of a signal …
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Reversible and imperceptible watermarking approach for ensuring the integrity and authenticity of brain MR images
… on relative Visual Grading Analysis (relative VGA) to define a perceptual threshold in which modifications become noticeable to radiographers. The proposed approach is then integrated into medical systems to verify its validity and applicability in a real application scenario of medical imaging …
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A Completely Integrated Warm-IF Receiver and a 10GS/s Analog-Delay Pipeline ADC for Radio-Telescope Applications
… (VCO), a mixer, and a variable-gain amplifier (VGA), based on CHAI design requirements, was implemented in 0.13 μm complementary metal-oxide semiconductor (CMOS) technology. An analog-to-digital converter (ADC) was implemented, based on the design requirements of the SKA, in 65 nm CMOS …
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Eavesdropping risks of the DisplayPort video interface
… computer displays using analog video interfaces (VGA) and older digital interfaces (LVDS, HDMI, DVI). DisplayPort is a newer interface with a significantly more complex signal structure, and in particular uses a linear-feedback shift register to scramble the transmitted pixel data. Due to …
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Epidemiología molecular de Staphylococcus aureus resistente a meticilina del linaje CC398 de distintos orígenes: resistencia, virulencia y contenido plasmídico
… de gran tamaño [lnu(B)], plásmidos movilizables [vga(A)], plásmidos conjugativos [cfr] y transposones [vga(A)-variante]. En algunos casos, se detectaron plásmidos (pUR2355, pUR4128, pUR3036, pUR3937, pUR5425) o entornos genéticos nuevos y se estableció una relación entre estos genes y algunas …
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Digital communication and control circuits for 60ghz fully integrated CMOS digital radio
… as linear equalizer, Gain Control loops (AGC, VGA), etc. Ultra high speed digital Input-Output buffers are used to provide an external data interface to the radio chipset. These high speed I/Os are also used in the gbps (gigabit-per-second) link for data transfer between the RF transceiver chip …
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A comparative study evaluating the performance of diagnostic radiography units and protocols for paediatric and adult chest radiography examinations
… – for this, a relative visual grading analysis (VGA) method was used. Additionally, signal to noise ratios (SNR), contrast to noise ratios (CNR) and conspicuity indices (CI) were calculated for all phantom image data in this study. Incident air karma (IAK) was measured using a solid-state …
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An investigation into methods for dose optimisation for paediatric AP pelvis projections when considering size variations
… IQ was assessed using relative and absolute VGA methods with an IQ scale, combining the sharpness and clarity of the visibility of bony anatomies. The radiation doses were measured by placing a dosimeter on the surface of each phantom. Analyses for optimisation included main effects, …
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Establishing an evidence-base for erect pelvis radiography : positioning, radiation dose and image quality
… positions. Visual grading analysis was used (VGA) to evaluate image quality. The effective dose and absorbed dose were calculated using PCXMC.During Phase Three, 60 patients were imaged in erect and supine positions. The paired pelvis X-ray images were then compared, taking into account …
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Receivers for energy efficient optical interconnects
… (VG-TIA) and a variable-gain amplifier (VGA) to achieve both low-noise and high-linearity operation. A prototype dual TIA chip is fabricated in a 0.13-um SiGe BiCMOS process. The presented TIA achieves 20 pA/sqrt(Hz) input referred noise density, 27 GHz 3-dB bandwidth, and 1.5% total …