An Aperture-Synthesis Radio Array Sized from Receiver Noise and Survey Speed: A Computed Design

This paper presents a computed design for a ground-based aperture-synthesis radio observatory of 214 parabolic antennas of 18 m diameter, and derives its performance from receiver noise, collecting area and baseline geometry rather than adopting the figures of any existing instrument. The total effective collecting area is 35,397 square metres, giving a system equivalent flux density of 1.95 Jy at 10 GHz for a system temperature of 25 K. The corresponding thermal noise is 0.257 microJy in one hour and 0.63 microJy in ten minutes over an 8 GHz dual-polarisation bandwidth. A longest baseline of 300 km sets an angular resolution of 0.021 arcseconds at 10 GHz, and the primary-beam field of view leads to a survey speed of 0.113 square degrees per hour to a depth of 1 microJy. The full installation is estimated at 10,744 tonnes and 3.40 MW of electrical power. All figures are computed from the stated assumptions; the design is simulated, not measured.