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In this report we present a model for phased array feed (PAF) and compare the model predictions with measurements. A theory for loss-less PAF is presented first. To develop the theory we ask the question -- what is the best $T_{sys}/eta_{ap}$ that can be achieved when a PAF is used on a telescope to observe a source at an angle $theta_s, phi_s$ from the boresight direction ? We show that a characteristic matrix for the {em system} (i.e. PAF+telescope+receiver) can be constructed starting from the signal-to-noise ratio of the observations and the best $T_{sys}/eta_{ap}$ can be obtained from the maximum eigenvalue of the characteristic matrix. For constructing the characteristic matrix, we derive the open-circuit voltage at the output of the antenna elements in the PAF due to (a) radiation from source, (b) radiation from ground (spillover), (c) radiation from sky background and (d) noise due to the receiver. The characteristic matrix is then obtained from the correlation matrices of these voltages. We then describe a modeling program developed to implement the theory presented here. Finally the model predictions are compared with results from test observations made toward Virgo A with a prototype PAF (Kite array) on the GBT (Roshi et al. 2015).
During February 2016, CSIRO Astronomy and Space Science and the Max-Planck-Institute for Radio Astronomy installed, commissioned and carried out science observations with a phased array feed (PAF) receiver system on the 64m diameter Parkes radio tele
We have measured the aperture-array noise temperature of the first Mk. II phased array feed that CSIRO has built for the Australian Square Kilometre Array Pathfinder telescope. As an aperture array, the Mk. II phased array feed achieves a beam equiva
We present first results from pilot observations using a phased array feed (PAF) mounted on the Parkes 64-m radio telescope. The observations presented here cover a frequency range from 1150 to 1480 MHz and are used to show the ability of PAFs to sup
We report results from a neutral hydrogen (HI) intensity mapping survey conducted with a Phased Array Feed (PAF) on the Parkes telescope. The survey was designed to cover ~ 380 deg^2 over the redshift range 0.3 < z < 1 (a volume of ~ 1.5 Gpc^3) in fo
This paper presents the measured sensitivity of CSIROs first Mk. II phased array feed (PAF) on an ASKAP antenna. The Mk. II achieves a minimum system-temperature-over-efficiency $T_mathrm{sys}/eta$ of 78 K at 1.23 GHz and is 95 K or better from 835 M