In this paper we will consider a problem of registration of radio signals from distant sources, natural (pulsars) or artificial (SETI signals). These signals possess a number of common properties, i.e. they are weak, almost indistinguishable from the background noise, are strongly localized on celestial sphere, have spectral characteristics smeared by dispersion on interstellar medium and Doppler drift, suffer from near-Earth electromagnetic interference. In this paper we will overview existing methods for registration of such signals and discuss some alternatives. We implement selected methods as data filters connected to data processing workflow, with 3D Virtual Environment as a frontend, integrate the methods into a system for radio astronomical monitoring StarWatch and apply them for detection of pulsar signals from BSA telescope at Pushchino Radio Astronomy Observatory and narrow band signals in SETI database (setilive.org).
