1,746 research outputs found

    A review of advances in pixel detectors for experiments with high rate and radiation

    Full text link
    The Large Hadron Collider (LHC) experiments ATLAS and CMS have established hybrid pixel detectors as the instrument of choice for particle tracking and vertexing in high rate and radiation environments, as they operate close to the LHC interaction points. With the High Luminosity-LHC upgrade now in sight, for which the tracking detectors will be completely replaced, new generations of pixel detectors are being devised. They have to address enormous challenges in terms of data throughput and radiation levels, ionizing and non-ionizing, that harm the sensing and readout parts of pixel detectors alike. Advances in microelectronics and microprocessing technologies now enable large scale detector designs with unprecedented performance in measurement precision (space and time), radiation hard sensors and readout chips, hybridization techniques, lightweight supports, and fully monolithic approaches to meet these challenges. This paper reviews the world-wide effort on these developments.Comment: 84 pages with 46 figures. Review article.For submission to Rep. Prog. Phy

    A mixed-signal integrated circuit for FM-DCSK modulation

    Get PDF
    This paper presents a mixed-signal application-specific integrated circuit (ASIC) for a frequency-modulated differential chaos shift keying (FM-DCSK) communication system. The chip is conceived to serve as an experimental platform for the evaluation of the FM-DCSK modulation scheme, and includes several programming features toward this goal. The operation of the ASIC is herein illustrated for a data rate of 500 kb/s and a transmission bandwidth in the range of 17 MHz. Using signals acquired from the test platform, bit error rate (BER) estimations of the overall FM-DCSK communication link have been obtained assuming wireless transmission at the 2.4-GHz ISM band. Under all tested propagation conditions, including multipath effects, the system obtains a BER = 10-3 for Eb/No lower than 28 dB.Ministerio de Ciencia y Tecnología TIC2003-0235

    Analog Testing, Characterization, and Low-Order Model Extraction using LabVIEW Automation

    Get PDF
    Testing circuits is a hands-on, time intensive process; it is also one of the most important steps in a design cycle. The most well designed circuit is only an academic exercise if it does not work in real life. The time and cost associated with bench level testing pales in comparison to testing for extreme environments. Testing in extreme heat, cold or radiation introduces a large set of challenges that are rarely encountered in standard bench level testing. The two most pronounced problems are the inaccessibility of the devices under test and time constraints, both short and protracted. Due to the physical properties of devices and circuits there is a short window in which all testing must be conducted for each incremental step during extreme environment tests. This time requirement does not present a significant challenge when testing a single circuit or device, but the cost associated with this testing is enough to encourage a more efficient method. The primary goal of this work is to reduce the time required to perform tests through the use of automation and parallel test schemes. The automation software chosen for this project was LabVIEW. LabVIEW is a graphical based programming language with an extensive library of functions for interfacing with test instrumentation. Due to the graphical nature of this language, display of measurement data is essentially a byproduct of the program. This allowed for confirmation of proper operation and immediate rectification if a problem was discovered. This paper will cover the key parameters of common devices and circuits, methods for extracting these parameters from other prevailing effect, and methods for automating these tests through the use of computer based tools such as LabVIEW

    The Development of a Capacitance-Based Biotelemetry System for Implantable Applications

    Get PDF
    Most modern biomedical implants implement some form of communications link between the implant and the outside world. This biotelemetry link has many requirements such as data bandwidth and power consumption. Designing an appropriate link that meets these requirements is one of the most significant engineering challenges associated with these implants. Communications methods that are currently used for this link include standard Radio Frequency (RF) approaches, inductively coupled approaches, and load modulation approaches. This thesis describes the development of a unique capacitance-based biotelemetry system for implantable applications. This system consists of two distinct parts: the implanted transmitter and the external body-mounted receiver. The prototype transmitter is based on a custom Application Specific Integrated Circuit (ASIC) fabricated using the AMI 1.5µ process. This ASIC encodes and transmits predetermined data packets by driving two electrodes in a slew-controlled manner, all contained within a biocompatible material. The receiver consists of charge-sensitive amplifier front end using a discriminator to distinguish individual bits. A Field Programmable Gate Array (FPGA) decodes the transmitted data and relays it to a PC- based LabVIEW interface. Test results using a saline-based human tissue model are presented
    corecore