Astrometric precision and knowledge of the point spread function are key ingredients for a wide range astrophysical studies including time-delay cosmography in which strongly lensed quasar systems used to determine Hubble constant other cosmological parameters. uncertainty on positions multiply-imaged sources contributes overall inferred distances therefore constant. Similarly, wings points (PS...

This paper presents the root-mean-squared tracking error performance analysis of a class of coherent digital delay-locked loops for multicode direct sequence spread spectrum signals in bandlimited correlated Rayleigh fading channels. In the transmit side, multiple independent PSK-modulated data streams in the in-phase and qudrature phase branches are spread by short mutually orthogonal codes be...

A channel sounding and communications experiment was performed in the Oslofjord, using eight bottom-mounted instrument units deployed a network configuration. Five were equipped with software-defined 4–8-kHz acoustic modem, programmed to transmit probe signals communication packets round-robin fashion. All transmitted waveforms recorded by all over 35 horizontal links 5 vertical links. The chan...

introduction :  despite  recent  advances  in  treatment  of  oral  cancer,  it  still causes high rates of mortality and morbidity worldwide. delays in diagnosis and treatment of these cancers greatly affect the prognosis.  this study aimed to assess the treatment delay and its relation to diagnostic delay among oral cancer patients in tehran, iran. materials and methods : we studied 100 patie...

The operation of an intelligent reflecting surface (IRS) under predictable receiver mobility is investigated. We develop a continuous time system model for multipath channels and discuss the optimal IRS configuration with respect to received power, Doppler spread, delay spread. It shown that power can be maximized without adding spread system. In numerical case study, we show having size just t...