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.

Phase-Only and Amplitude-Phase Only Synthesis of Dual-Beam Pattern Linear Antenna Arrays Using Floating-Point Genetic Algorithms

Abstract: In this paper, we present a comparison study between phase-only and amplitude-phase synthesis of symmetrical dual-pattern linear antenna arrays using floating-point or real-valued genetic algorithms (GA). Examples include a sum pattern and a sector beam pattern. In the former, phase is only optimized with predetermined Gaussian amplitude distribution of fixed dynamic range ratio (|amax/amin|) and in the latter, both are optimized with less dynamic range ratio than the former and yet share a common amplitude distribution.

Development of the DEPFET sensor with signal compression: A large format X-ray imager with mega-frame readout capability for the European XFEL

Abstract: We present the development of the DSSC instrument: an ultra-high speed detector system for the new European XFEL in Hamburg. The DSSC will be able to record X-ray images with a maximum frame rate of 4.5 MHz. The system is based on a silicon pixel sensor with a DEPFET as a central amplifier structure and has detection efficiency close to 100% for X-rays from 0.5 keV up to 10 keV. The sensor will have a size of approximately 210 × 210 mm composed of 1024 × 1024 pixels with hexagonal shape. Two hundred fifty six mixed signal readout ASICs are bump-bonded to the detector. They are designed in 130 nm CMOS technology and provide full parallel readout. The signals coming from the sensor are processed by an analog filter, immediately digitized by 8-bit ADCs and locally stored in an SRAM, which is able to record at least 640 frames. In order to fit the dynamic range of about 104 photons of 1 keV per pixel into a reasonable output signal range, achieving at the same time single 1 keV photon resolution, a non-linear characteristic is required. The proposed DEPFET provides the needed dynamic range compression at the sensor level. The most exciting and challenging property is that the single 1 keV photon resolution and the high dynamic range are accomplished within the 220 ns frame rate of the system. The key properties and the main design concepts of the different building blocks of the system are discussed. Measurements with the analog front-end of the readout ASIC and a standard DEPFET have already shown a very low noise which makes it possible to achieve the targeted single photon resolution for 1 keV photons at 4.5 MHz and also for 0.5 keV photons at half of the speed. In the paper the new experimental results obtained coupling a single pixel to an 8 × 8 ASIC prototype are shown. This 8 × 8 ASIC comprises the complete readout chain from the analog front-end to the ADC and the memory. The characterization of a newly fabricated non-linear DEPFET is presented for the first time.

Continuous-wave terahertz system with a 60 dB dynamic range

Abstract: We have developed a high-performance continuous-wave terahertz imaging system based on photomixing. The emitter and detector are driven by compact, unstabilized, single-mode diode lasers. The all-optoelectronic, homodyne detection scheme yields both amplitude and phase information, and with careful optimization and matching of both emitter and receiver, a 60 dB dynamic range, at 0.53 THz, can be routinely achieved. This replicates the performance of established pulsed THz imagers at this frequency. (c) 2005 American Institute of Physics.

Digital Dynamic Range Compressor Design—A Tutorial and Analysis

Abstract: Dynamic range compression, despite being one of the most widely used audio effects, is still poorly understood, and there is little formal knowledge and analysis of compressor design techniques. In this tutorial we describe several different approaches to digital dynamic range compressor design. Digital implementations of several classic analog approaches are given, as well as designs from recent literature, and new approaches that address possible issues. Several design techniques are analyzed and compared, including RMS and peak–based approaches, feedforward and feedback designs, and linear and log domain level detection. We explain what makes the designs sound different and provide metrics to analyze their quality. Finally, we provide recommendations for high performance compressor design.

A High Dynamic Range CMOS Image Sensor With Inpixel Light-to-Frequency Conversion

Abstract: A high dynamic range CMOS image sensor with inpixel light-to-frequency conversion has been designed. The prototype chip was fabricated in a standard 0.18-mum single-poly six-metal CMOS technology. The experimental results show that, operating at 1.2 V, the sensor can achieve a linear dynamic range of over 115 dB and an overall dynamic range of over 130 dB