In order to increase the operating speed of a CMOS image sensor (CIS), a new technique of digital correlated double sampling (CDS) is described. In general, the fixed pattern noise (FPN) of a CIS has been reduced with the subtraction algorithm between the reset signal and pixel signal. This is because a single-slope analog-to-digital converter (ADC) has been normally adopted in the conventional...

A maximal-ratio angle-diversity receiver is composed of multiple sectors with relatively small field-of-views. Each sector estimates the signal-to-noise ratio (SNR) of the collected signal and its gain made proportional to the relation i / σ 2 , where i and σ represent the average signal and the shot noise root mean square (rms) values, respectively. The output signals of all sectors are then c...

Variable-gain amplifier (VGA) is one of the basic building blocks of many communication systems. In this paper we present a novel structure of VGA with 22 db of gain range and 220 MHz of bandwidth frequency variation. This circuit combines a voltage to current (V-I) converter and two-stage CMOS amplifier to achieve programmable gain and bandwidth .The gain is varied by changing the input voltag...

Abstrac t A digital intermediate frequency (IF) to RF transmitter targeted for 2GHz wideband code division multiple access (WCDMA) is presented. The proposed transmitter integrates a 3-level digital IF current-steering cell, an up-conversion mixer with a tuned load and an RF variable gain amplifier (RF VGA) with an embedded semidigital finite impulse response (FIR) reconstruction filter. A 4-or...

RATIONALE AND OBJECTIVES The purpose of this study was to utilize computer assistance effectively for both easy and accurate magnetic resonance (MR) image-guided microwave thermocoagulation therapy of liver tumors. MATERIALS AND METHODS An open configuration MR scanner and a microwave coagulator at 2.45 GHz were used. Navigation software, a 3D Slicer, was customized to combine fluoroscopic MR...

Two variable gain amplifiers (VGAs) that adopt new approximated exponential equations are proposed in this paper. The dB-linear range of the proposed VGAs is extended more than what the approximated exponential equations predict by a bias circuit technique that adopts negative feedback. The proposed VGAs feature wide gain variation, low-power, high linearity, wide control signal range, and smal...

A computer vision setup is presented for the automated detection and multi-view 3D reconstruction of lightning discharges. The system is designed to operate autonomously in a continuous mode and provide accurate position information of the lightning discharge path and impact point relative to its surrounding area. Extensive tests in a medium scale laboratory environment show that a relative mea...

Applying recent advances in multi-imager capture and multi-projector display, we combine capabilities through the Nizza multimedia dataflow architecture to deliver low-cost wide-VGA-quality low-latency autostereoscopic 3D display of live video on a single PC. Supporting multiple users as they observe and interact against a life-sized display surface responsive to their positions, this facility ...