32,803 research outputs found

    A space communication study Progress report, 15 Sep. 1966 - 15 Mar. 1967

    Get PDF
    Space communications studies of optimal signal reception, threshold extension, signal detection against noise, channel simulation, and synchronization technique

    A space communications study Status report, 15 Dec. 1968 - 15 Mar. 1969

    Get PDF
    Harmonic distortion in frequency demodulator using feedback, delta modulation, recursive signal processing techniques, and multipath fadin

    A space communication study Final report, 15 Sep. 1967 - 15 Sep. 1968

    Get PDF
    Transmitting and receiving analog and digital signals through noisy media - space communications stud

    A Space Communications Study Final Report, Sep. 15, 1965 - Sep. 15, 1966

    Get PDF
    Reception of frequency modulated signals passed through deterministic and random time-varying channel

    A space communications study Final report, 15 Sep. 1968 - 15 Sep. 1969

    Get PDF
    Analog and digital signal reception problems through noisy channels, and computerized digital TV system for space communication

    Analysis of an F.M. Discriminator with Fading Signal plus Additive Gaussian Noise

    Get PDF
    Fading signal plus additive Gaussian noise applied to frequency modulation discriminator for determining fading effects on threshol

    Identification of Coulomb blockade and macroscopic quantum tunneling by noise

    Full text link
    The effects of Macroscopic Quantum Tunneling (MQT) and Coulomb Blockade (CB) in Josephson junctions are of considerable significance both for the manifestations of quantum mechanics on the macroscopic scale and potential technological applications. These two complementary effects are shown to be clearly distinguishable from the associated noise spectra. The current noise is determined exactly and a rather sharp crossover between flux noise in the MQT and charge noise in the CB regions is found as the applied voltage is changed. Related results hold for the voltage noise in current-biased junctions.Comment: 6 pages, 3 figures, epl.cls include

    XMM-Newton Observation of the Northwest Radio Relic Region in Abell 3667

    Full text link
    Abell 3667 is the archetype of a merging cluster with radio relics. The NW radio relic is the brightest cluster relic or halo known, and is believed to be due to a strong merger shock. We have observed the NW relic for 40 ksec of net XMM time. We observe a global decline of temperature across the relic from 6 to 1 keV, similar to the Suzaku results. Our new observations reveal a sharp change of both temperature and surface brightness near the position of the relic. The increased X-ray emission on the relic can be equivalently well described by either a thermal or nonthermal spectral model. The parameters of the thermal model are consistent with a Mach number M~2 shock and a shock speed of ~1200 km s^-1. The energy content of the relativistic particles in the radio relic can be explained if they are (re)-accelerated by the shock with an efficiency of ~0.2%. Comparing the limit on the inverse Compton X-ray emission with the measured radio synchrotron emission, we set a lower limit to the magnetic field in the relic of 3 muG. If the emission from the relic is non-thermal, this lower limit is in fact the required magnetic field.Comment: 11 pages, ApJ in pres
    • …
    corecore