NSGen Noise Generator for Absolute Calibration for SPIDER Radio Telescopes
The NSGen Noise Generator for Absolute Calibration is designed for SPIDER radio telescopes and allow RadioUniversePRO software to calculate the flux in Jy of a radio source or sky area, by compensating atmospheric attenuation or any gain loss because of different factors (for example, antenna deformation because of its weight). The NSGen noise generator is installed on the SPIDER H-FEED for 1420 MHz frequency and connects directly to the H142-One radio astronomy receiver of SPIDER radio telescopes.
The goal of the Gain Calibration procedure is to calibrate the noise generator by performing several Total Power measurements (using BBC filters previously defined by the user) on a set of radio sources with radio flow known from the literature. Having selected the radio sources on which to calibrate, the procedure automatically plans the slewing, at different elevations, always considering the theoretical flux in Jy. Therefore, for each radio source, these Total Power measurements will be performed:
- ON source (on the radio source, with noise generator OFF)
- OFF source (off radio source with noise generator OFF)
- CAL (off radio source with noise generator ON)
Measurements recorded in every step are used to calibrate the noise generator and the radio telescope and this will allow to record antenna temperature and flux measurements.
The NSGen Noise Generator for Absolute Calibration comes with noise generator (1), connection cable for H142-One receiver (2), metallic clamps for installation (3).
The NSGen Noise Generator for Absolute Calibration can be used only with SPIDER radio telescopes with the Gain Calibration feature of RadioUniversePRO.