Dynamic range

About: Dynamic range is a research topic. Over the lifetime, 7576 publications have been published within this topic receiving 101739 citations. The topic is also known as: DNR & DR.

Pulse width modulation: A novel readout scheme for high energy photon detection

Abstract: In standard PET scintillation detection, the energy, timing, and location of the incoming photon are recovered using analog signal processing techniques The energy and location information are processed using an analog-to-digital (ADC) converter that samples an analog value that is proportional to the integral of the charge created by the scintillation event We propose to change the paradigm and modulate the width (rather than amplitude) of a digital pulse to be proportional to the integral of the charge created The analog value of the outgoing digital pulses is recovered by using a time-to-digital converter (TDC) in the back-end electronics, without the need for an ADC Note that in this new scenario the same TDC used to record the time of the event is used to recover the amplitude The main performance parameter that must be optimized is the dynamic range versus the dead-time of the front-end detector The goal is an 8-bit dynamic range for this pulse-width modulation (PWM) scheme, which is adequate for high resolution PET systems based on semiconductor detectors such as avalanche photodiodes (APD) or cadmium zinc telluride (CZT) A novel circuit has been designed, fabricated, and tested for the proposed PWM readout scheme This circuit is different than previously developed time over threshold pulse width modulation circuits used in high energy physics PWM techniques simplify the routing to the back end electronics without degrading the performance of the system A readout architecture based on PWM processes digital rather than analog pulses, which can be easily multiplexed, enabling one to achieve very high channel density required for ultra-high resolution, 3-D positioning PET detector systems

An 84 dB dynamic range 62.5–625 kHz bandwidth clock-scalable noise-shaping SAR ADC with open-loop integrator using dynamic amplifier

Abstract: This paper proposes a noise shaping SAR ADC with open-loop integrator using dynamic amplifier. The proposed integrator for a delta-sigma modulator requires low-gain open-loop amplifiers, therefore low power dynamic amplifier can be used. Moreover, binary-mode dynamic element matching is proposed to overcome the nonlinearity of a capacitor DAC. An SNDR of 83.5 dB, a power consumption 273.4 μW, and a Schreier figure of merit of 173 dB with a bandwidth of 250 kHz is achieved. In addition, clock scalability has been confirmed for a wide sampling-rate range of 2.5 MS/s to 25 MS/s.

The computer-controlled solar radio spectrometer ‘IKARUS’

Abstract: The radiospectrometer IKARUS is a fully computer-controlled instrument covering the frequency band 0.11 to 1 GHz in steps of 1 MHz. It can automatically detect solar radio bursts and then write, on magnetic tape, 2000 measurements per second of intensity and circular polarization. The frequencies to be measured can be readily programmed in the band, compromising between frequency and time resolution. Reference noise sources are switched in automatically by the computer to calibrate the receiver at each frequency. The dynamic range is about 50 dB, recorded logarithmically with 8 bit resolution. The novelty of the instrument is its ability to measure broadband calibrated spectra (flux and degree of polarization) in the very interesting region of the lower corona.

Optimization of externally modulated analog optical links

Abstract: Analog fiber-optic links using an integrated-optical intensity modulator have been demonstrated and analyzed. Experimental links operate at frequencies from 40 MHz to 22 GHz with electrical gain up to 11 dB, noise figure as low as 6 dB, and intermodulation-free dynamic range of up to 113 dB-Hz2/3. The gain, noise figure, and dynamic range are shown to have a simple dependence upon a few link design parameters. Other factors affecting link performance, such as stimulated Brillouin scattering, interferometric intensity noise, modulator linearization, and addition of an optical amplifier, are also discussed briefly.© (1991) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

Traveling wave parametric amplifier with Josephson junctions using minimal resonator phase matching

Abstract: Josephson parametric amplifiers have become a critical tool in superconducting device physics due to their high gain and quantum-limited noise. Traveling wave parametric amplifiers (TWPAs) promise similar noise performance while allowing for significant increases in both bandwidth and dynamic range. We present a TWPA device based on an LC-ladder transmission line of Josephson junctions and parallel plate capacitors using low-loss amorphous silicon dielectric. Crucially, we have inserted $\lambda/4$ resonators at regular intervals along the transmission line in order to maintain the phase matching condition between pump, signal, and idler and increase gain. We achieve an average gain of 12\,dB across a 4\,GHz span, along with an average saturation power of -92\,dBm with noise approaching the quantum limit.