Signal processing aspects of the sample clock frequency offset scheme for the SKA1 mid telescope array

In the proposed sample clock frequency offset (SCFO) scheme, the received signals at each antenna of the Square Kilometre Array Mid Telescope Array are sampled at slightly different sample rates. Subsequently, these sampled sequences are digitally re-sampled to a common sample rate prior to channelization and correlation/ beamforming. In this paper, the signal processing aspects of the SCFO scheme as it relates to the correlator and beamformer (CBF) of the SKA1 Mid Telescope are discussed. Here, it is shown that sample clock-related self-interference and out-of-band interference de-correlates improving the quality of correlated/ beamformed results.